Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 33
Filter
Add more filters








Publication year range
1.
Eur J Pharm Sci ; 193: 106671, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38104907

ABSTRACT

PURPOSE: A novel 18F-radiolabeled somatostatin analogue, [Al18F]NODA-MPAA-HTA, was synthesized and evaluated for positron emission tomography (PET) imaging of Neuroendocrine tumors (NETs). [Al18F]NODA-MPAA-HTA was designed and synthesized by conjugating 18F nuclide with a modified KE108 peptide, a somatostatin analog with high affinity for all five subtypes of somatostatin receptors (SSTR 1-5), through coupling a bifunctional chelator (NODA) to target somatostatin receptor (SSTR) positive tumors. METHODS: The amino group of KE108 peptide, a SSTRs-targeting pharmacophore, was conjugated with the carboxyl group of NODA by a condensation reaction to obtain the labeling precursor of [Al18F]NODA-MPAA-HTA, in which its precursor was obtained through Fmoc solid-phase methods. A novel methodology for Al18F labeling of chelating agent-biomolecule conjugates was used to synthesize [Al18F]NODA-MPAA-HTA. In vitro stabilities of [Al18F]NODA-MPAA-HTA were evaluated by incubating it in saline or bovine serum for 2 h. Ex vivo biodistribution and in vivo imaging of [Al18F]NODA-MPAA-HTA were further investigated to evaluate its SSTRs targeting ability and feasibility for the diagnosis of NETs using PET imaging. RESULTS: [Al18F]NODA-MPAA-HTA was synthesized using a one-step 18F-AlF labeling procedure resulting in moderate radiochemical yield (60-80 %, non-decay corrected) and high radiochemical purity (>95 %). It exhibited good hydrophilicity and excellent stability in vitro, with a molar activity of 122 GBq/µmol. At 30 min and 60 min, the uptake of [Al18F] NODA-MPAA-HTA by HEK293-SSTR2 cells was 5.47 ± 0.97 %/105 cells and 12.11 ± 0.32 %/105 cells, respectively. The affinity of [Al18F]NODA-MPAA-HTA for SSTR2 was determined to be 8.77 ± 1.14 nM. In micro-PET imaging of HEK293-SSTR2 tumor-bearing mice, [Al18F]NODA-MPAA-HTA showed high tumor uptake of radioactivity and a high tumor-to-muscle ratio. Biodistribution results confirmed that radioactivity uptake in the tumor was significantly higher than that in the muscle by more than five-fold (P<0.001). Furthermore, the relatively low bone uptake of [Al18F]NODA-MPAA-HTA suggested that defluorination did not occur in vivo. These preliminary results provide experimental evidence for further study of Al18F-labeled somatostatin analogues as tumor probes for PET imaging of NETs. CONCLUSION: Fluorine-18 is widely used as a radionuclide for the production of radiopharmaceuticals for positron emission tomography (PET). Due to its short half-life (T1/2,109.8 min), its ease of production will facilitate the widespread dissemination of this radiopharmaceutical. A high-quality [Al18F]NODA-MPAA-HTA was synthesized with satisfactory yield. This radiopharmaceutical demonstrated higher tumor uptake and better tumor-to-muscle contrast, resulting to excellent image quality. These findings suggest that the novel 18F-labeled somatostatin analogue, [Al18F]NODA-MPAA-HTA, is a promising tool for PET imaging of NETs.


Subject(s)
Neuroendocrine Tumors , Somatostatin , Humans , Mice , Animals , Receptors, Somatostatin/metabolism , Neuroendocrine Tumors/diagnostic imaging , Radiopharmaceuticals/chemistry , Tissue Distribution , HEK293 Cells , Positron-Emission Tomography/methods , Fluorine Radioisotopes/chemistry , Peptides/chemistry , Cell Line, Tumor
2.
Adv Sci (Weinh) ; 9(28): e2202748, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35975421

ABSTRACT

Evaluating the delamination process in the synthesis of MXenes (2D transition metal carbides and nitrides) is critical for their development and applications. However, the preparation of large defect-free MXene flakes with high yields is challenging. Here, a power-focused delamination (PFD) strategy is demonstrated that can enhance both the delamination efficiency and yield of large Ti3 C2 Tx MXene nanosheets through repetitive precipitation and vortex shaking processes. Following this protocol, a colloidal concentration of 20.4 mg mL-1 of the Ti3 C2 Tx MXene can be achieved after five PFD cycles, and the yield of the basal-plane-defect-free Ti3 C2 Tx nanosheets reaches 61.2%, which is 6.4-fold higher than that obtained using the sonication-exfoliation method. Both nanometer-thin devices and self-supporting films exhibit excellent electrical conductivities (≈25 000 and 8260 S cm-1 for a 1.8 nm thick monolayer and 11 µm thick film, respectively). Hydrodynamic simulations reveal that the PFD method can efficiently concentrate the shear stress on the surface of the unexfoliated material, leading to the exfoliation of the nanosheets. The PFD-synthesized large MXene nanosheets exhibit superior electrical conductivities and electromagnetic shielding (shielding effectiveness per unit volume: 35 419 dB cm2 g-1 ). Therefore, the PFD strategy provides an efficient route for the preparation of high-performance single-layer MXene nanosheets with large areas and high yields.

3.
Zootaxa ; 5091(3): 443-454, 2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35391238

ABSTRACT

Two new species of the genus Sinamma Lin Li, 2014, Sinamma quadrata Tong Li, sp. nov. (male, female) and Sinamma yingae Tong Li, sp. nov. (male, female) are described from Guangdong, China. The geographic distribution of the genus is updated and a key to all known species is provided.


Subject(s)
Spiders , Animals , China , Female , Male
4.
ACS Appl Mater Interfaces ; 14(3): 3939-3948, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35014782

ABSTRACT

The preparation of highly dispersed metal catalysts with strong electronic metal-support interactions (EMSIs) is of great significance. In this study, oxygen vacancies (OVs) were generated on the surfaces of Co3O4 nanorods (NRs) through NaBH4 treatment, and then the generated surface OVs were used to anchor gold clusters. The resulting catalyst was used for the hydrodeoxygenation (HDO) of vanillin based on transfer hydrogenation with alcohol donors. The conversion of vanillin and the selectivity to 2-methoxy-4-methylphenol (MMP) both reached 99% under the optimized reaction conditions, and these values were significantly higher than those obtained for the gold catalyst supported on the untreated Co3O4 NRs. The obtained results were verified by theoretical calculations and experimental data and confirmed the existence of strong EMSIs between the OV-enriched Co3O4 NRs (Co3O4 NRs-OVs) and the gold clusters, which allows electron transfer from the Co3O4 NRs to gold. Increasing the number of electrons on the gold surface can promote the catalytic hydrogen transfer of alcohol, in addition to selectively adsorbing the C═O group in vanillin to improve the selectivity toward MMP. This strategy based on the OV-anchoring of metals onto the surface of a support can be extended to other metals, thereby providing a promising method for the design of advanced and highly efficient metal catalysts.

5.
Minerva Med ; 113(3): 506-512, 2022 Jun.
Article in English | MEDLINE | ID: mdl-32512977

ABSTRACT

BACKGROUND: Acute liver injury (ALI) is associated with the occurrence and progress of intrahepatic inflammation. Recent studies have shown that ADAM10, a significant member of metalloproteinase family, has modulated the inflammation level in various neurologic diseases. However, it is elusive whether ADAM10 regulation exert a hepatic protective effect on ALI by the suppression of inflammation level. The study aimed to explore the regulated function of ADAM10 on acute liver injury. METHODS: C57BL/6J mice (eight-week-old male) were carried out intraperitoneal injection of tetrachloromethane (CTC) to provoke ALI. ADAM10 loaded in adeno-associated viral vectors (AAV-ADAM10) or short hairpin RNA loaded in lentivirus aimed at murine ADAM10 mRNA (sh-RNA-ADAM10) were respectively delivered to mice via tail intravenous injection to achieve overexpression or silence of ADAM10. Western blotting, reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), immunohistochemical (IHC) and hematoxylin and eosin (HE) staining were conducted to measure ADAM10 alteration, inflammation level, histology and liver function. RESULTS: We show that the expression of ADAM10 markedly increases in CTC-induced injured liver tissues. Moreover, we demonstrate that the knockdown of ADAM10 attenuates the intrahepatic inflammation and protects hepatic histology and function in ALI mice; however, the overexpression of ADAM10 aggravates inflammation and liver lesion. CONCLUSIONS: The above suggested that the inhibition of ADAM10 ameliorates ALI through inhibiting inflammation. Our research provides novel view on the ADAM10 modulation of process of ALI by the inflammation aspect and verify a potential target for the therapy of ALI in the future.


Subject(s)
ADAM10 Protein , Acute Lung Injury , Amyloid Precursor Protein Secretases , Membrane Proteins , ADAM10 Protein/genetics , Acute Lung Injury/chemically induced , Acute Lung Injury/metabolism , Acute Lung Injury/pathology , Amyloid Precursor Protein Secretases/genetics , Animals , Inflammation/metabolism , Liver/pathology , Male , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL
6.
China CDC Wkly ; 3(10): 211-213, 2021 Mar 05.
Article in English | MEDLINE | ID: mdl-34594851

ABSTRACT

SUMMARY: What is already known on this topic? Clusters of COVID-19 cases often happened in small settings (e.g., families, offices, school, or workplaces) that facilitate person-to-person virus transmission, especially from a common exposure. What is added by this report? On January 10 and 11, 2021, an individual gave three product promotional lectures in Tonghua City, Jilin Province, that ultimately led to a 74-case cluster of COVID-19. Our investigation determined the outbreak to be an import-related COVID-19 superspreading cluster event in which elderly, retired people were exposed to the infected individual during his promotional lectures, which were delivered in a confined space and lasted several hours. What are the implications for public health practice? Routine activities, such as attending a lecture in a classroom, can provide an environment conducive to COVID-19 superspreading events because respiratory viruses can spread easily and widely. We suggest local government to strengthen infection control management, reduce unnecessary indoor large gathering activities, and promote wearing of masks, especially during wintertime in the north of China. Health education for elderly people should promote use of effective personal protection and emphasize the importance of wearing masks.

7.
China CDC Wkly ; 3(19): 405-408, 2021 May 07.
Article in English | MEDLINE | ID: mdl-34594894

ABSTRACT

What is already known on this topic? Contact tracing and testing with isolated medical care of identified cases is a key strategy for interrupting chains of transmission of COVID-19 and reducing mortality associated with COVID-19. At the early phases of the COVID-19 pandemic, due to test capacity limitations, case finding often started from suspected cases. What is added by this report? The index patient infected 74 individuals who were close contacts that were identified through contact tracing, and exposed individuals were monitored in quarantine with daily polymerase chain reaction (PCR) testing. All individuals were asymptomatic initially, but all PCR-positive individuals eventually developed symptoms. Infectivity was documented up to 8 days before being confirmed as a symptomatic case, approximately 4 days before turning PCR positive. What are the implications for public health practice? During an outbreak, we suggest tracing close contacts from both PCR-positive individuals and suspected cases, rather than from suspected cases alone. Due to the long period of infectivity before turning PCR positive or developing symptoms, close contacts that had contact with a newly PCR positive case within 4 days should be judged as at risk of being infected; close contacts that had contact within 8 days of a newly symptomatic case should be judged as at risk being infected.

8.
Zookeys ; 1052: 55-69, 2021.
Article in English | MEDLINE | ID: mdl-34393552

ABSTRACT

A new genus, Paramolotra Tong & Li, gen. nov., including two new species, Paramolotra pome Tong & Li, sp. nov. (♂♀) and Paramolotra metok Tong & Li, sp. nov. (♂♀), is described from Tibet, China. Morphological descriptions and photographic illustrations of the two new species are given.

9.
Food Res Int ; 140: 109990, 2021 02.
Article in English | MEDLINE | ID: mdl-33648225

ABSTRACT

Modulating the inhomogeneous distribution of fat globules within an emulsion gel is now being considered an effective method to increase the perception of fat-related sensory attributes. However, the methods for preparing the inhomogeneous gel were relatively complicated in previous studies. In the present study, milks enriched with different sizes of fat globule were obtained and then used to prepare glucono-δ-lactone-induced milk gels. The gels with different spatial distributions of fat globules were obtained through natural creaming. To ensure the high fat content layer exist on the gel surface, the two gels made from the same milk were superimposed from the bottom to form a new gel. In situ confocal microscopy showed that under the same overall fat content, the superimposed gel containing larger fat globules (L-L gel) exhibited the greatest inhomogeneity in microstructure with the highest average surface fat area fraction (10.9%), and the largest difference in fat content between the surface and the inside layers (9.1%). To illustrate the effect of inhomogeneous distribution of fat globules in gels on the perception of fat-related attributes, quantitative descriptive sensory analysis as well as the lubrication properties measurement under simulated oral processing conditions were carried out. The results showed the superimposed gels exhibited higher creaminess ratings and lower friction coefficients at 20 mm/s than those of the original gels. Overall, the study modulated the spatial distribution of fat globules in acid milk gels through natural creaming and superimposition and illustrated its positive effect on the perception of fat-related sensory attributes.


Subject(s)
Glycolipids , Milk , Animals , Gels , Glycoproteins , Lipid Droplets , Perception
10.
PLoS One ; 16(1): e0243903, 2021.
Article in English | MEDLINE | ID: mdl-33411811

ABSTRACT

Tinnitus, the phantom perception of sound, often occurs as a clinical sequela of auditory traumas. In an effort to develop an objective test and therapeutic approach for tinnitus, the present study was performed in blast-exposed rats and focused on measurements of auditory brainstem responses (ABRs), prepulse inhibition of the acoustic startle response, and presynaptic ribbon densities on cochlear inner hair cells (IHCs). Although the exact mechanism is unknown, the "central gain theory" posits that tinnitus is a perceptual indicator of abnormal increases in the gain (or neural amplification) of the central auditory system to compensate for peripheral loss of sensory input from the cochlea. Our data from vehicle-treated rats supports this rationale; namely, blast-induced cochlear synaptopathy correlated with imbalanced elevations in the ratio of centrally-derived ABR wave V amplitudes to peripherally-derived wave I amplitudes, resulting in behavioral evidence of tinnitus. Logistic regression modeling demonstrated that the ABR wave V/I amplitude ratio served as a reliable metric for objectively identifying tinnitus. Furthermore, histopathological examinations in blast-exposed rats revealed tinnitus-related changes in the expression patterns of key plasticity factors in the central auditory pathway, including chronic loss of Arc/Arg3.1 mobilization. Using a formulation of N-acetylcysteine (NAC) and disodium 2,4-disulfophenyl-N-tert-butylnitrone (HPN-07) as a therapeutic for addressing blast-induced neurodegeneration, we measured a significant treatment effect on preservation or restoration of IHC ribbon synapses, normalization of ABR wave V/I amplitude ratios, and reduced behavioral evidence of tinnitus in blast-exposed rats, all of which accorded with mitigated histopathological evidence of tinnitus-related neuropathy and maladaptive neuroplasticity.


Subject(s)
Acetylcysteine , Benzenesulfonates , Disease Models, Animal , Evoked Potentials, Auditory, Brain Stem/drug effects , Hair Cells, Auditory, Inner/metabolism , Hearing Loss, Noise-Induced , Tinnitus , Acetylcysteine/pharmacology , Acetylcysteine/therapeutic use , Animals , Benzenesulfonates/pharmacology , Benzenesulfonates/therapeutic use , Biomarkers/metabolism , Hair Cells, Auditory, Inner/pathology , Hearing Loss, Noise-Induced/drug therapy , Hearing Loss, Noise-Induced/physiopathology , Male , Rats , Tinnitus/drug therapy , Tinnitus/physiopathology
11.
Artif Cells Nanomed Biotechnol ; 48(1): 408-414, 2020 Dec.
Article in English | MEDLINE | ID: mdl-31913714

ABSTRACT

Overexpression of CD30 has been reported on the surface of some T-cell lymphomas, especially on Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL). CD30 targeted immunotherapy has good clinical therapy response. We have produced a novel antibody drug conjugates (ADCs)-anti-CD30-LDM, which shows attractive tumour-targeting capability and extremely potent antitumor efficacy. To further investigate biological characteristics and promote clinical translation of anti-CD30-LDM, we constructed a radiolabeled 123I-anti-CD30-LDM to evaluate the biodistribution characteristics. The anti-CD30-LDM was radioiodinated by the Iodogen method. The radiochemical purity of 123I-anti-CD30-LDM was more over 98%, and the specific activity of 240.5 MBq/mg. The stability and the specificity of 123I-anti-CD30-LDM were evaluated in vitro. Cellular binding assays were used to evaluate the binding capabilities in CD30-positive Karpas299 cells and CD30-negative Raji cells. B-NDG mice bearing Karpas 299 and Raji xenografts were used for in vivo biodistribution studies. Our results demonstrated that anti-CD30-LDM as an ideal ADC targeted to CD30, which was labelled easily with 123I and obtained the sufficient yields. The 123I-anti-CD30-LDM preserved specific binding to CD30 in vitro and uptake in tumour xenografts in B-NDG mice. These results are encouraging for anti-CD30-LDM as a promising clinical translational candidate for various CD30 positive lymphomas and other diseases.


Subject(s)
Antineoplastic Agents, Immunological , Iodine Radioisotopes , Ki-1 Antigen/antagonists & inhibitors , Lymphoma, Large-Cell, Anaplastic , Neoplasm Proteins/antagonists & inhibitors , Radiopharmaceuticals , Animals , Antineoplastic Agents, Immunological/chemistry , Antineoplastic Agents, Immunological/pharmacokinetics , Antineoplastic Agents, Immunological/pharmacology , Humans , Iodine Radioisotopes/chemistry , Iodine Radioisotopes/pharmacokinetics , Iodine Radioisotopes/pharmacology , Lymphoma, Large-Cell, Anaplastic/drug therapy , Lymphoma, Large-Cell, Anaplastic/metabolism , Lymphoma, Large-Cell, Anaplastic/pathology , Mice , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/pharmacology , Xenograft Model Antitumor Assays
12.
Mol Ther ; 26(5): 1313-1326, 2018 05 02.
Article in English | MEDLINE | ID: mdl-29680697

ABSTRACT

Deafness is commonly caused by the irreversible loss of mammalian cochlear hair cells (HCs) due to noise trauma, toxins, or infections. We previously demonstrated that small interfering RNAs (siRNAs) directed against the Notch pathway gene, hairy and enhancer of split 1 (Hes1), encapsulated within biocompatible poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) could regenerate HCs within ototoxin-ablated murine organotypic cultures. In the present study, we delivered this sustained-release formulation of Hes1 siRNA (siHes1) into the cochleae of noise-injured adult guinea pigs. Auditory functional recovery was measured by serial auditory brainstem responses over a nine-week follow-up period, and HC regeneration was evaluated by immunohistological evaluations and scanning electron microscopy. Significant HC restoration and hearing recovery were observed across a broad tonotopic range in ears treated with siHes1 NPs, beginning at three weeks and extending out to nine weeks post-treatment. Moreover, both ectopic and immature HCs were uniquely observed in noise-injured cochleae treated with siHes1 NPs, consistent with de novo HC production. Our results indicate that durable cochlear HCs were regenerated and promoted significant hearing recovery in adult guinea pigs through reversible modulation of Hes1 expression. Therefore, PLGA-NP-mediated delivery of siHes1 to the cochlea represents a promising pharmacologic approach to regenerate functional and sustainable mammalian HCs in vivo.


Subject(s)
Hair Cells, Auditory , Nanoparticles , RNA, Small Interfering/genetics , Regeneration , Transcription Factor HES-1/genetics , Animals , Cochlea/physiology , Female , Guinea Pigs , Hearing/genetics , Immunohistochemistry , RNA, Small Interfering/administration & dosage , Regeneration/genetics
13.
Anal Chim Acta ; 985: 91-100, 2017 Sep 08.
Article in English | MEDLINE | ID: mdl-28864199

ABSTRACT

4-Carboxy-benzoboroxole was designed and synthesized. It was then combined with the modification effect of polyethyleneimine (PEI) for the preparation of boronate affinity silica stationary phase. The stationary phase showed improved binding strength with dissociation constant (Kd) towards xanthosine as low as 2.48 × 10-4 M. The column showed excellent selectivity, high binding capacities (88.3 µmol adenosine g-1, pH 7.0) and the lowest binding pH (4.0 for cytidine and as low as 2.24 for xanthosine). These binding properties were superior to the existing boronate affinity materials, facilitating the selective extraction of trace cis-diol compounds in complex samples and greatly expanding the application scope of boronate affinity chromatography. In addition, the column showed secondary separation capability under acidic conditions and this secondary separation capability was investigated thoroughly. It was found that the separation was pH-dependent and mainly determined by binding strength with the possibility of involvement of other interaction, providing alternative strategy for the separation of cis-diol compounds. The feasibility and practicability were demonstrated through the selective enrichment of nucleosides in urine samples and the results indicated the excellent performance and great potential for the extraction of trace cis-diol compounds in complex samples.


Subject(s)
Boronic Acids , Chromatography, Affinity , Nucleosides/urine , Silicon Dioxide , Humans
14.
Free Radic Biol Med ; 108: 627-643, 2017 07.
Article in English | MEDLINE | ID: mdl-28438658

ABSTRACT

Cochlear neurodegeneration commonly accompanies hair cell loss resulting from aging, ototoxicity, or exposures to intense noise or blast overpressures. However, the precise pathophysiological mechanisms that drive this degenerative response have not been fully elucidated. Our laboratory previously demonstrated that non-transgenic rats exposed to blast overpressures exhibited marked somatic accumulation of neurotoxic variants of the microtubule-associated protein, Tau, in the hippocampus. In the present study, we extended these analyses to examine neurodegeneration and pathologic Tau accumulation in the auditory system in response to blast exposure and evaluated the potential therapeutic efficacy of antioxidants on short-circuiting this pathological process. Blast injury induced ribbon synapse loss and retrograde neurodegeneration in the cochlea in untreated animals. An accompanying perikaryal accumulation of neurofilament light chain and pathologic Tau oligomers were observed in neurons from both the peripheral and central auditory system, spanning from the spiral ganglion to the auditory cortex. Due to its coincident accumulation pattern and well-documented neurotoxicity, our results suggest that the accumulation of pathologic Tau oligomers may actively contribute to blast-induced cochlear neurodegeneration. Therapeutic intervention with a combinatorial regimen of 2,4-disulfonyl α-phenyl tertiary butyl nitrone (HPN-07) and N-acetylcysteine (NAC) significantly reduced both pathologic Tau accumulation and indications of ongoing neurodegeneration in the cochlea and the auditory cortex. These results demonstrate that a combination of HPN-07 and NAC administrated shortly after a blast exposure can serve as a potential therapeutic strategy for preserving auditory function among military personnel or civilians with blast-induced traumatic brain injuries.


Subject(s)
Acetylcysteine/therapeutic use , Antioxidants/therapeutic use , Benzenesulfonates/therapeutic use , Blast Injuries/drug therapy , Hair Cells, Auditory/physiology , Neurodegenerative Diseases/drug therapy , Neurons/physiology , Vestibulocochlear Nerve Diseases/drug therapy , Animals , Auditory Cortex/pathology , Cell Death , Cells, Cultured , Male , Rats , Rats, Inbred Strains , Spiral Ganglion/pathology , Unfolded Protein Response , tau Proteins/metabolism
15.
Molecules ; 21(11)2016 Nov 19.
Article in English | MEDLINE | ID: mdl-27869782

ABSTRACT

A series of novel amide derivatives of cembranoid neocrotocembraneic acid were designed and synthesized. The antiproliferative activities of these derivatives were evaluated against three human tumor cell lines (the human cervical cancer cell line HeLa, chronic myeloid leukemia cell line K562 and leukemia multidrug-resistant cell line K562/A02). Some of the synthesized compounds exhibited moderate to good activity against all three cancer cell lines. Particularly, compound 8a exhibited more potent antiproliferative activity than the reference drug etoposide against drug-resistant cell line K562/A02, indicating that it possessed a great potential for further development as a multidrug resistance modulator by structural modification.


Subject(s)
Amides/chemistry , Amides/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Diterpenes/chemistry , Diterpenes/pharmacology , Amides/chemical synthesis , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Diterpenes/chemical synthesis , HeLa Cells , Humans , K562 Cells , Molecular Structure
16.
Oxid Med Cell Longev ; 2016: 4159357, 2016.
Article in English | MEDLINE | ID: mdl-27034735

ABSTRACT

Traumatic brain injury (TBI) can lead to early onset dementia and other related neurodegenerative diseases. We previously demonstrated that damage to the central auditory pathway resulting from blast-induced TBI (bTBI) could be significantly attenuated by a combinatorial antioxidant treatment regimen. In the current study, we examined the localization patterns of normal Tau and the potential blast-induced accumulation of neurotoxic variants of this microtubule-associated protein that are believed to potentiate the neurodegenerative effects associated with synaptic dysfunction in the hippocampus following three successive blast overpressure exposures in nontransgenic rats. We observed a marked increase in the number of both hyperphosphorylated and oligomeric Tau-positive hilar mossy cells and somatic accumulation of endogenous Tau in oligodendrocytes in the hippocampus. Remarkably, a combinatorial regimen of 2,4-disulfonyl α-phenyl tertiary butyl nitrone (HPN-07) and N-acetylcysteine (NAC) resulted in striking reductions in the numbers of both mossy cells and oligodendrocytes positively labeled for these pathological Tau immunoreactivity patterns in response to bTBI. This treatment strategy represents a promising therapeutic approach for simultaneously reducing or eliminating both primary auditory injury and nonauditory changes associated with bTBI-induced hippocampal neurodegeneration.


Subject(s)
Acetylcysteine/therapeutic use , Antioxidants/therapeutic use , Benzenesulfonates/therapeutic use , Blast Injuries/drug therapy , Brain Injuries, Traumatic/drug therapy , Hippocampus/drug effects , Protein Aggregation, Pathological/prevention & control , tau Proteins/metabolism , Acetylcysteine/pharmacology , Animals , Antioxidants/pharmacology , Benzenesulfonates/pharmacology , Blast Injuries/complications , Blast Injuries/metabolism , Blast Injuries/pathology , Brain Injuries, Traumatic/complications , Brain Injuries, Traumatic/metabolism , Brain Injuries, Traumatic/pathology , Cytoprotection/drug effects , Disease Models, Animal , Hippocampus/metabolism , Hippocampus/pathology , Male , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Protein Aggregation, Pathological/metabolism , Protein Aggregation, Pathological/pathology , Rats , Rats, Long-Evans
17.
Molecules ; 20(7): 12266-79, 2015 Jul 06.
Article in English | MEDLINE | ID: mdl-26154885

ABSTRACT

A series of novel podophyllotoxin derivatives were designed and synthesized. The cytotoxic activities of these compounds were tested against three tumor cell lines (HeLa, K562, and K562/A02). Most of the derivatives (IC50 = 1-20 µM) were found to have stronger cell growth inhibitory activity than positive control etoposide. Among them, 4ß-N-[(E)-(5-((4-(4-nitrophenyl)-piperazin-1-yl)methyl)furan-2-yl)prop-2-en-1-amine]-4-desoxy-podophyllotoxin (9l) demonstrated significant inhibitory activity against HeLa, K562, and K562/A02 cell lines with IC50 values of 7.93, 6.42, 6.89 µM, respectively.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Podophyllotoxin/chemical synthesis , Podophyllotoxin/pharmacology , Cell Line, Tumor , Humans , In Vitro Techniques
18.
Eur J Med Chem ; 85: 498-507, 2014 Oct 06.
Article in English | MEDLINE | ID: mdl-25113878

ABSTRACT

Cancer multidrug resistance (MDR) is a common cause of treatment failure in cancer patients. Increased expression of permeability glycoprotein (P-gp), which is also known as MDR-1, is the main cause of multidrug resistance. Podophyllotoxin derivatives hold great promise in the battle to overcome multidrug resistance, as they can induce cytotoxicity through multiple mechanisms. Here, we synthesized sixteen novel podophyllotoxin derivatives and evaluated their cytotoxicities in human cancer cell lines, HeLa, K562 and K562/A02. Some of these compounds were more potent than etoposide, a clinically relevant inhibitor of DNA repair enzymes. In particular, compound 5p exhibited the most potent activity toward drug-resistant K562/A02 cells, as it robustly inhibited tumor cell proliferation and induced apoptosis. Furthermore, preliminary investigation suggested that 5p inhibited the expression of MDR-1 in K562/A02 cells more effectively than etoposide.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Podophyllotoxin/chemical synthesis , Podophyllotoxin/pharmacology , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Proliferation/drug effects , Chemistry Techniques, Synthetic , Drug Resistance, Multiple/drug effects , Gene Expression Regulation, Neoplastic/drug effects , HeLa Cells , Humans , K562 Cells , Podophyllotoxin/analogs & derivatives , RNA, Messenger/genetics , RNA, Messenger/metabolism
19.
J Pharm Biomed Anal ; 90: 35-44, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24321516

ABSTRACT

Xin-Ke-Shu (XKS) is a patent drug used for coronary heart diseases in China. This study evaluated the protective effect of XKS against isoproterenol (ISO)-induced myocardial infarction (MI). For its underlying mechanism in rats with MI, a metabonomic approach was developed using ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/QTOF-MS). Plasma metabolites were profiled in MI rats, pretreated orally with or without XKS. Two genres of metabolic biomarkers were used to elucidate the pharmacological action of XKS: pathological biomarkers and pharmaco biomarkers. Fifteen metabolites significantly varying between MI rats and normal rats were characterized as potential pathological biomarkers related to MI, including L-acetylcarnitine (1), L-isoleucyl-L-proline (2), tyramine (3), isobutyryl-L-carnitine (4), phytosphingosine (5), sphinganine (6), L-palmitoylcarnitine (7), lysoPC(18:0) (8), uric acid (9), L-tryptophan (10), lysoPC(18:2) (11), lysoPC(16:0) (12), docosahexaenoic acid (13), arachidonic acid (14) and linoleic acid (15). Among them, eight (1-6, 9 and 10) were first reported as pathological biomarkers related to ISO-induced MI, which mainly involved into fatty acid ß-oxidation pathway, sphingolipid metabolism, proteolysis, tryptophan metabolism and purine metabolism. The metabolites significantly varying between MI rats with and without XKS pretreatment were considered as pharmaco biomarkers. A total of 17 pharmaco biomarkers were recognized, including 15 pathological biomarkers (1-15), hexanoylcarnitine (16) and tetradecanoylcarnitine (17). The results suggested that pretreatment of XKS protected metabolic perturbations in rats with MI, major via lipid pathways, amino acid metabolism and purine metabolism, which also provided a promising approach for evaluating the pharmacodynamics and mechanism of traditional Chinese medicines (TCM) formulas.


Subject(s)
Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/pharmacology , Mass Spectrometry/methods , Myocardial Infarction/prevention & control , Administration, Oral , Animals , Biomarkers/analysis , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/pharmacology , Disease Models, Animal , Drugs, Chinese Herbal/administration & dosage , Isoproterenol/toxicity , Male , Medicine, Chinese Traditional/methods , Metabolomics/methods , Myocardial Infarction/metabolism , Rats , Rats, Wistar
20.
PLoS One ; 8(11): e80138, 2013.
Article in English | MEDLINE | ID: mdl-24224042

ABSTRACT

Blast-induced traumatic brain injury has dramatically increased in combat troops in today's military operations. We previously reported that antioxidant treatment can provide protection to the peripheral auditory end organ, the cochlea. In the present study, we examined biomarker expression in the brains of rats at different time points (3 hours to 21 days) after three successive 14 psi blast overpressure exposures to evaluate antioxidant treatment effects on blast-induced brain injury. Rats in the treatment groups received a combination of antioxidants (2,4-disulfonyl α-phenyl tertiary butyl nitrone and N-acetylcysteine) one hour after blast exposure and then twice a day for the following two days. The biomarkers examined included an oxidative stress marker (4-hydroxy-2-nonenal, 4-HNE), an immediate early gene (c-fos), a neural injury marker (glial fibrillary acidic protein, GFAP) and two axonal injury markers [amyloid beta (A4) precursor protein, APP, and 68 kDa neurofilament, NF-68]. The results demonstrate that blast exposure induced or up-regulated the following: 4-HNE production in the dorsal hippocampus commissure and the forceps major corpus callosum near the lateral ventricle; c-fos and GFAP expression in most regions of the brain, including the retrosplenial cortex, the hippocampus, the cochlear nucleus, and the inferior colliculus; and NF-68 and APP expression in the hippocampus, the auditory cortex, and the medial geniculate nucleus (MGN). Antioxidant treatment reduced the following: 4-HNE in the hippocampus and the forceps major corpus callosum, c-fos expression in the retrosplenial cortex, GFAP expression in the dorsal cochlear nucleus (DCN), and APP and NF-68 expression in the hippocampus, auditory cortex, and MGN. This preliminary study indicates that antioxidant treatment may provide therapeutic protection to the central auditory pathway (the DCN and MGN) and the non-auditory central nervous system (hippocampus and retrosplenial cortex), suggesting that these compounds have the potential to simultaneously treat blast-induced injuries in the brain and auditory system.


Subject(s)
Antioxidants/therapeutic use , Blast Injuries/drug therapy , Brain Injuries/drug therapy , Amyloidogenic Proteins/metabolism , Animals , Blast Injuries/metabolism , Brain Injuries/metabolism , Cochlear Nucleus/metabolism , Geniculate Bodies/metabolism , Glial Fibrillary Acidic Protein/metabolism , Male , Neurofilament Proteins/metabolism , Rats
SELECTION OF CITATIONS
SEARCH DETAIL