Zfp423 encodes a 30-zinc finger transcription factor that intersects several canonical signaling pathways. Zfp423 mutations result in ciliopathy-related phenotypes, including agenesis of the ...cerebellar vermis in mice and Joubert syndrome (JBTS19) and nephronophthisis (NPHP14) in humans. Unlike most ciliopathy genes, Zfp423 encodes a nuclear protein and its developmental expression is complex, leading to alternative proposals for cellular mechanisms. Here we show that Zfp423 is expressed by cerebellar granule cell precursors, that loss of Zfp423 in these precursors leads to cell-intrinsic reduction in proliferation, loss of response to Shh, and primary cilia abnormalities that include diminished frequency of both Smoothened and IFT88 localization. Loss of Zfp423 alters expression of several genes encoding key cilium components, including increased expression of Tulp3. Tulp3 is a direct binding target of Zfp423 and reducing the overexpression of Tulp3 in Zfp423-deficient cells suppresses Smoothened translocation defects. These results define Zfp423 deficiency as a bona fide ciliopathy, acting upstream of Shh signaling, and indicate a mechanism intrinsic to granule cell precursors for the resulting cerebellar hypoplasia.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Colorectal cancer is one of the most common cancers worldwide and chemotherapy is the main approach for the treatment of advanced and recurrent cases. Developing an effective complementary therapy ...could help to improve tumor suppression efficiency and control adverse effects from chemotherapy.
is a folk medicine for treating various forms of cancer, but its effect on colorectal cancer is largely unexplored. The aim of the present study is to investigate the tumor suppression efficacy and the mechanism of action of the ethanolic extract from
(EEPP) in DLD-1 human colorectal carcinoma cells and to evaluate its combined effect with chemotherapeutic drug doxorubicin. The data indicated that EEPP induced DLD-1 cell death via the upregulation of the autophagy markers, without triggering p53- and caspase-3-dependent apoptosis. Moreover, EEPP treatment in combination with doxorubicin enhanced cytotoxicity in these tumor cells. Pennogenin 3-
-beta-chacotrioside and polyphyllin VI were isolated from EEPP and identified as the main candidate active components. Our results suggest that EEPP deserves further evaluation for development as complementary chemotherapy for colorectal cancer.
Chemotherapy is the main approach for treating advanced and recurrent carcinoma, but the clinical performance of chemotherapy is limited by relatively low response rates, drug resistance, and adverse ...effects that severely affect the quality of life of patients. An association between epithelial-mesenchymal transition (EMT) and chemotherapy resistance has been investigated in recent studies. Our recent studies have found that the aqueous extract of Solanum nigrum (AESN) is a crucial ingredient in some traditional Chinese medicine formulas for treating various types of cancer patients and exhibits antitumor effects. We evaluated the suppression of EMT in MCF-7 breast cancer cells treated with AESN. The mitochondrial morphology was investigated using Mitotracker Deep-Red FM stain. Our results indicated that AESN markedly inhibited cell viability of MCF-7 breast cancer cells through apoptosis induction and cell cycle arrest mediated by activation of caspase-3 and production of reactive oxygen species. Furthermore, mitochondrial fission was observed in MCF-7 breast cancer cells treated with AESN. In addition to elevation of E-cadherin, downregulations of ZEB1, N-cadherin, and vimentin were found in AESN-treated MCF-7 breast cancer cells. These results suggested that AESN could inhibit EMT of MCF-7 breast cancer cells mediated by attenuation of mitochondrial function. AESN could be potentially beneficial in treating breast cancer cells, and may be of interest for future studies in developing integrative cancer therapy against proliferation, metastasis, and migration of breast cancer cells.
Syndecan-2 induced filopodia before spinogenesis; therefore, filopodia formation was used here as a model to study the early downstream signaling of syndecan-2 that leads to spinogenesis. Screening ...using kinase inhibitors indicated that protein kinase A (PKA) is required for syndecan-2-induced filopodia formation in both human embryonic kidney cells and hippocampal neurons. Because neurofibromin, a syndecan-2-binding partner, activates the cyclic adenosine monophosphate pathway, the role of neurofibromin in syndecan-2-induced filopodia formation was investigated by deletion mutant analysis, RNA interference, and dominant-negative mutant. The results showed that neurofibromin mediates the syndecan-2 signal to PKA. Among actin-associated proteins, Enabled (Ena)/vasodilator-stimulated phosphoprotein (VASP) were predicted as PKA effectors downstream of syndecan-2, as Ena/VASP, which is activated by PKA, induces actin polymerization. Indeed, when the activities of Ena/VASP were blocked, syndecan-2 no longer induced filopodia formation. Finally, in addition to filopodia formation, neurofibromin and Ena/VASP contributed to spinogenesis. This study reveals a novel signaling pathway in which syndecan-2 activates PKA via neurofibromin and PKA consequently phosphorylates Ena/VASP, promoting filopodia and spine formation.
Without a vaccine, hepatitis C virus (HCV) remains a global medical and socio-economic burden, predisposing about 170 million carriers worldwide to end-stage liver diseases including cirrhosis and ...hepatocellular carcinoma. Although the recently developed direct-acting antivirals (DAAs) have revolutionized hepatitis C treatment, most of them are unsuitable for monotherapy due to risks of resistance, thus necessitating combination with interferon (IFN)-alpha, ribavirin, or additional DAAs. More importantly, the high cost associated with the DAAs restricts their accessibility to most parts of the world. Developing novel cost-effective anti-HCV therapeutics may help expand the scope of antivirals and treatment strategies against hepatitis C. Herein, we applied an activity-based and fraction-guided analysis of extracts from the medicinal plant Phyllanthus urinaria (P. urinaria), which yielded fraction 13 (F13) as possessing the most potent inhibitory activity against early viral entry of cell-culture HCV infection. Chemical analysis (silica gel chromatography followed by ESI LC-MS plus (1)H and (13)C NMR) of F13 identified loliolide (LOD), a monoterpenoid lactone, as a novel inhibitor of HCV entry. Specifically, LOD could efficiently inactivate HCV free virus particles, abrogate viral attachment, and impede viral entry/fusion, with minimal effect on viral replication/translation, particle production, and induction of type I IFN host antiviral immune response. ELISA-based binding analysis confirmed the monoterpenoid's ability in efficiently blocking HCV particle attachment to the host cell surface. Furthermore, LOD could inhibit infection by several genotypic strains of HCV. This is the first report characterizing P. urinaria and its bioactive compound LOD as potent HCV entry inhibitors, which merit further evaluation for development as candidate antiviral agents against hepatitis C.
Chemotherapy, a major approach was used in carcinoma treatment, always involves the development of drug resistance as well as side-effects that affect the quality of patients' lives. An association ...between epithelial-mesenchymal transition (EMT) and chemotherapy resistance was established recently. We demonstrate in this paper that the aqueous extract of Paris polyphylla (AEPP)-a traditional Chinese medicine-can be used in various cancer types for suppression of carcinogenesis. We evaluated the suppressions of EMT and mitochondrial activity by AEPP treatment in a high-glucose (HG) induced-human ovarian carcinoma cell line (OVCAR-3 cells). The mitochondrial morphology was investigated using MitoTracker Deep Red FM staining. Our results indicated that AEPP reduced the viability of OVCAR-3 cells considerably through induction of apoptosis. However, this inhibitory potential of AEPP was attenuated by HG induction in OVCAR-3 cells. The levels of estrogen-related receptor (ERR)-alpha activator and peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha were elevated by HG induction, but were suppressed by AEPP treatment. Down-regulations of cell survival and EMT were oberved in OVCAR-3 cells through suppression of PGC-1alpha by AEPP treatment. These results were confirmed through PGC-1alpha knockdown and overexpression in OVCAR-3 cells. Thus, AEPP can be beneficial for treating ovarian cancer and has potential for development of an integrative cancer therapy against ovarian cancer proliferation, metastasis, and migration.
Abstract
BACKGROUND
Preganglionic cervical root transection (PCRT) is the most severe type of brachial plexus injury. In some cases, surgical procedures must be postponed for ≥3 wk until ...electromyographic confirmation. However, research works have previously shown that treating PCRT after a 3-wk delay fails to result in functional recovery.
OBJECTIVE
To assess whether the immunosuppressive drug sirolimus, by promoting neuroprotection in the acute phase of PCRT, could enable functional recovery in cases of delayed repair.
METHODS
First, rats received a left 6th to 8th cervical root transection, after which half were administered sirolimus for 1 wk. Markers of microglia, astrocytes, neurons, and autophagy were assessed at days 7 and 21. Second, animals with the same injury received nerve grafts, along with acidic fibroblast growth factor and fibrin glue, 3 wk postinjury. Sirolimus was administered to half of them for the first week. Mechanical sensation, grasping power, spinal cord morphology, functional neuron survival, nerve fiber regeneration, and somatosensory-evoked potentials (SSEPs) were assessed 1 and 23 wk postinjury.
RESULTS
Sirolimus was shown to attenuate microglial and astrocytic proliferation and enhance neuronal autophagy and survival; only rats treated with sirolimus underwent significant sensory and motor function recovery. In addition, rats who achieved functional recovery were shown to have abundant nerve fibers and neurons in the dorsal root entry zone, dorsal root ganglion, and ventral horn, as well as to have SSEPs reappearance.
CONCLUSION
Sirolimus-induced neuroprotection in the acute stage of PCRT enables functional recovery, even if surgical repair is performed after a 3-wk delay.
Chemotherapy is one of the main approach for ovarian cancer. Cancer stem cells (CSCs) escape chemotherapy and lead to chemoresistance. We previously demonstrated that cordycepin (Cd) inhibited ...metastasis in human ovarian carcinoma cells, the aim of this study is to investigate the effects of Cd on ovarian cancer stemness. TGF-beta was used to induce chemoresistance of chemotherapeutic agent cisplatin in SKOV-3 ovarian cancer cells. After treating with 100 μM of Cd, cell viability, the percentage of cancer stem cells, and the levels of matrix metalloproteinases (MMPs) were decreased in TGF-beta-induced SKOV-3 cells. Treatment of Cd recovered E-cadherin levels and inhibited vimentin levels while TGF-beta treatment significantly increased the expression of vimentin and PGC-1alpha, and decreased E-cadherin levels in SKOV-3 cells, indicating that the action of Cd on cancer stemness may contribute to the regulation of epithelial-mesenchymal transition (EMT). Cd efficiently attenuated chemoresistance caused by TGF-beta in SKOV-3 cancer stem cells to promote the cytotoxicity of cisplatin.
Advanced glycation end products (AGEs) signal through the receptor for AGE (RAGE), which can lead to hepatic fibrosis in hyperglycemia and hyperlipidemia. We investigated the inhibitory effect of ...aqueous extracts from Solanum nigrum (AESN) on AGEs-induced RAGE signaling and activation of hepatic stellate cells (HSCs) and hyperglycemia induced by high-fat diet with ethanol.
An animal model was used to evaluate the anti-hepatic fibrosis activity of AESN in rats fed a high-fat diet (HFD; 30%) with ethanol (10%). Male Wistar rats (4 weeks of age) were randomly divided into four groups (n = 6): (1) control (basal diet); (2) HFD (30%) + ethanol (10%) (HFD/ethanol); (3) HFD/ethanol + AESN (100 mg/kg, oral administration); and (4) HFD/ethanol + pioglitazone (10 mg/kg, oral administration) and treated with HFD for 6 months in the presence or absence of 10% ethanol in dietary water.
We found that AESN improved insulin resistance and hyperinsulinemia, and downregulated lipogenesis via regulation of the peroxisome proliferator-activated receptor α (PPARα), PPARγ co-activator (PGC-1α), carbohydrate response element-binding protein (ChREBP), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) mRNA levels in the liver of HFD/ethanol-treated rats. In turn, AESN may delay and inhibit the progression of hepatic fibrosis, including α-smooth muscle actin (α-SMA) inhibition and MMP-2 production.
These results suggest that AESN may be further explored as a novel anti-fibrotic strategy for the prevention of liver disease.
Silibinin is a flavonolignan that is well established for its robust antiviral activity against HCV infection and has undergone several clinical trials for the management of hepatitis C. Despite its ...potency, silibinin suffers from poor solubility and bioavailability, restricting its clinical use. To overcome this limitation, we developed highly bioavailable silibinin nanoparticles (SB-NPs) and evaluated their efficiency against HCV infection.
SB-NPs were prepared using a nanoemulsification technique and were physicochemically characterised. Infectious HCV culture systems were used to evaluate the influence of SB-NP on the virus life cycle and examine their antioxidant activity against HCV-induced oxidative stress. The safety profiles of SB-NP, in vivo pharmacokinetic studies and antiviral activity against infection of primary human hepatocytes were also assessed.
SB-NP consisted of nanoscale spherical particles (<200 nm) encapsulating amorphous silibinin at >97% efficiency and increasing the compound's solubility by >75%. Treatment with SB-NP efficiently restricted HCV cell-to-cell transmission, suggesting that they retained silibinin's robust anti-HCV activity. In addition, SB-NP exerted an antioxidant effect via their free radical scavenging function. Oral administration of SB-NP in rodents produced no apparent in vivo toxicity, and pharmacokinetic studies revealed an enhanced serum level and superior biodistribution to the liver compared with non-modified silibinin. Finally, SB-NP efficiently reduced HCV infection of primary human hepatocytes.
Due to SB-NP's enhanced bioavailability, effective anti-HCV activity and an overall hepatoprotective effect, we suggest that SB-NP may be a cost-effective anti-HCV agent that merits further evaluation for the treatment of hepatitis C.