Weihong Feng

Publications (19)83.1 Total impact

• Article: Biodegradation of Single-Walled Carbon Nanotubes by Eosinophil Peroxidase

  Fernando T Andón, Alexandr A Kapralov, Naveena Yanamala, Weihong Feng, Arjang Baygan, Benedict J Chambers, Kjell Hultenby, Fei Ye, Muhammet S Toprak, Birgit D Brandner, Andrea Fornara, Judith Klein-Seetharaman, Gregg P Kotchey, Alexander Star, Anna A Shvedova, Bengt Fadeel, Valerian E Kagan
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  ABSTRACT: Eosinophil peroxidase (EPO) is one of the major oxidant-producing enzymes during inflammatory states in the human lung. The degradation of single-walled carbon nanotubes (SWCNTs) upon incubation with human EPO and H2 O2 is reported. Biodegradation of SWCNTs is higher in the presence of NaBr, but neither EPO alone nor H2 O2 alone caused the degradation of nanotubes. Molecular modeling reveals two binding sites for SWCNTs on EPO, one located at the proximal side (same side as the catalytic site) and the other on the distal side of EPO. The oxidized groups on SWCNTs in both cases are stabilized by electrostatic interactions with positively charged residues. Biodegradation of SWCNTs can also be executed in an ex vivo culture system using primary murine eosinophils stimulated to undergo degranulation. Biodegradation is proven by a range of methods including transmission electron microscopy, UV-visible-NIR spectroscopy, Raman spectroscopy, and confocal Raman imaging. Thus, human EPO (in vitro) and ex vivo activ
  Small 02/2013; · 8.35 Impact Factor
• Article: Oxidized phospholipids as biomarkers of tissue and cell damage with a focus on cardiolipin.

  Alejandro K Samhan-Arias, Jing Ji, Olga M Demidova, Louis J Sparvero, Weihong Feng, Vladimir Tyurin, Yulia Y Tyurina, Michael W Epperly, Anna A Shvedova, Joel S Greenberger, Hülya Bayır, Valerian E Kagan, Andrew A Amoscato
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  ABSTRACT: Oxidized phospholipid species are important, biologically relevant, lipid signaling molecules that usually exist in low abundance in biological tissues. Along with their inherent stability issues, these oxidized lipids present themselves as a challenge in their detection and identification. Often times, oxidized lipid species can co-chromatograph with non-oxidized species making the detection of the former extremely difficult, even with the use of mass spectrometry. In this study, a normal-phase and reverse-phase two dimensional high performance liquid chromatography (HPLC)-mass spectrometric system was applied to separate oxidized phospholipids from their non-oxidized counterparts, allowing unambiguous detection in a total lipid extract. We have utilized bovine heart cardiolipin as well as commercially available tetralinoleoyl cardiolipin oxidized with cytochrome c (cyt c) and hydrogen peroxide as well as with lipoxygenase to test the separation power of the system. Our findings indicate that oxidized species of not only cardiolipin, but other phospholipid species, can be effectively separated from their non-oxidized counterparts in this two dimensional system. We utilized three types of biological tissues and oxidative insults, namely rotenone treatment of lymphocytes to induce mitochondrial damage and cell death, pulmonary inhalation exposure to single walled carbon nanotubes, as well as total body irradiation, in order to identify cardiolipin oxidation products, critical to the cell damage/cell death pathways in these tissues following cellular stress/injury. Our results indicate that selective cardiolipin (CL) oxidation is a result of a non-random free radical process. In addition, we assessed the ability of the system to identify CL oxidation products in the brain, a tissue known for its extreme complexity and diversity of CL species. The ability of the two dimensional HPLC-mass spectrometric system to detect and characterize oxidized lipid products will allow new studies to be formulated to probe the answers to biologically important questions with regard to oxidative lipidomics and cellular insult. This article is part of a Special Issue entitled: Oxidized phospholipids - their properties and interactions with proteins.
  Biochimica et Biophysica Acta 03/2012; 1818(10):2413-23. · 4.66 Impact Factor
• Article: [Determination of four anthraquinones in Sanhuang tablets by QAMS].

  Yuying Wang, Weihong Feng, Fei Yang, Qiwei Zhang, Lina Ji, Dongying Li, Zhimin Wang
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  ABSTRACT: To establish a quality evaluation method, quantitative analysis of multi-component with a single-marker (QAMS) to determine the contents of four rhubarb anthraquinones in Sanhuang tablets. Emodin was used as the internal reference substance, the relative correlation factors (RCF) of rhein, chrysophanol and physcion to emodin were calculated and evaluated. The contents of these four anthraquinones were determined by the external standard method and QAMS, respectively. Rationality, feasibility and repeatability of the QAMS method was verified by comparing the results obtained from the two different methods. RCFs of rhein, chrysophanol and physcion to emodin against Sanhuang tablets were 1.13, 1.46 and 1.01, respectively, indicating good reproducibilities. The two methods did not show significant difference in results. The QAMS method can be used a new quality assessment model for quantity of anthraquinones in Sanhuang tablets.
  Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 01/2012; 37(2):212-7.
• Article: Mitochondrial injury after mechanical stretch of cortical neurons in vitro: biomarkers of apoptosis and selective peroxidation of anionic phospholipids.

  Jing Ji, Yulia Y Tyurina, Minke Tang, Weihong Feng, Donna B Stolz, Robert S B Clark, David F Meaney, Patrick M Kochanek, Valerian E Kagan, Hülya Bayır
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  ABSTRACT: Mechanical injury of neurites accompanied by rupture of mitochondrial membranes may lead to immediate nonspecific release and spreading of pro-apoptotic factors and activation of proteases, that is, execution of apoptotic program. In the current work, we studied the time course of the major biomarkers of apoptosis as they are induced by exposure of rat cortical neurons to mechanical stretch. By using transmission electron microscopy, we found that mitochondria in the neurites were damaged early (1 h) after mechanical stretch injury whereas somal mitochondria were significantly more resistant and demonstrated structural damage and degenerative mitochondrial changes at a later time point after stretch (12 h). We also report that the stretch injury caused immediate activation of reactive oxygen species production followed by selective oxidation of a mitochondria-specific phospholipid, cardiolipin, whose individual peroxidized molecular species have been identified and quantified by electrospray ionization mass spectrometry analysis. Most abundant neuronal phospholipids - phosphatidylcholine, phophatidylethanolamine - did not undergo oxidative modification. Simultaneously, a small-scale release of cytochrome c was observed. Notably, caspase activation and phosphatidylserine externalization - two irreversible apoptotic events designating a point of no return - are substantially delayed and do not occur until 6-12 h after the initial impact. The early onset of reactive oxygen species production and cytochrome c release may be relevant to direct stretch-induced damage to mitochondria. The delayed emergence of apoptotic neuronal death after the immediate mechanical damage to mitochondria suggests a possible window of opportunity for targeted therapies.
  Journal of neurotrauma 09/2011; 29(5):776-88. · 4.25 Impact Factor
• Article: [A quantitative method for simultaneous assay of five ingredients with one marker in Salvia miltiorrhiza].

  Fei Yang, Zhimin Wang, Qiwei Zhang, Weihong Feng
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  ABSTRACT: To establish a new quantitative method for simultaneous determination of multi-components in Salvia miltiorrhiza by using one chemical reference substance and validate its feasibilities. The new quality evaluation method, quantitative analysis of multi-components by singer-marker (QAMS), was established and validated with S. miltiorrhiza . Five main ingredients were selected as analytes to evaluate the quatity and their relative correlation factors (RCF) were determined by HPLC-DAD. Within the linear range, the values of RCF at 280 nm of sodium danshensu to protocatechuic aldehyde, rosmarinic acid, lithospermic acid and salvianolic acid B were 7.559, 2.901, 1.825 and 1.746, respectively. The contents of danshensu in the samples of S. miltiorrhiza were determined by using the external standard method, and the contents of the four other ingredients were calculated by their RCFS. The contents of these four ingredients in all samples were also determined by the external standard method. Within a certain range, the RCFs showed good reproducibility (RSD 1.0%-2.5%). No significant differences were observed between the quantitative results of the two methods. It is feasible and suitable to evaluate the quality of S. miltiorrhiza and its processed products by QAMS.
  Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 09/2011; 36(17):2372-9.
• Article: [Quantitative method for simultaneous assay of four coumarins with one marker in fraxini cortex].

  Weihong Feng, Zhimin Wang, Qiwei Zhang, Limei Liu, Jinyu Wang, Fei Yang
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  ABSTRACT: To establish a new quantitative method for simultaneous determination of multi-coumarins in Fraxini Cortex by using one chemical reference substance, and validate its feasibilities. The new quality evaluation method, quantitative analysis of multi-components by singer-marker (QAMS), was established and validated with Fraxini Cortex. Four main coumarins were selected as analytes to evaluate the quality and their relative correlation factors (RCF) were determined by HPLC-DAD. Within the linear range, the values of RCF at 340 nm of aesculin to asculetin, fraxin and fraxetin were 1.771, 0.799, 1.409, respectively. And the contents of aesculin in samples of Fraxini Cortex were authentically determined by the external standard method, and the contents of the three other coumarins were calculated by their RCF. The contents of these four coumarins in all samples were also determined by the external standard method. Within a certain range, the RCF had a good reproducibility (RSD 2.5%-3.9%). Significant differences were not observed between the quantitative results of two methods. It is feasible and suitable to evaluate the quality of Fraxini Cortex and its Yinpian by QAMS.
  Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 07/2011; 36(13):1782-9.
• Article: [Quantitative analysis of four alkaloids in Xianglian preparations by QAMS method].

  Jingjing Kong, Jingjing Zhu, Zhimin Wang, Qiwei Zhang, Weihong Feng
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  ABSTRACT: To examine the feasibilities of the method, quantitative analysis of multi-components by single marker (QAMS) for determination of four alkaloids in Xianglian preparations. A HPLC method was developed to determine the contents of four alkaloids, epiberberine, coptisine, palmatine and berberine in Xianglian preparations. Berberine was selected as the internal reference substance, and 3 relative correction factors to berberine were calculated. The contents of the four alkaloids in 16 batches of samples were determined by both external standard method and QAMS. The new method was evaluated by comparing the quantitative results with of the external standard method. No significant differences were found between the quantitative results of four alkaloids in 16 batches of samples determined by the two methods. QAMS is feasible for determination of four alkaloids simultaneously, and the developed method can be used for quality control of Xiang Lian preparations.
  Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 06/2011; 36(11):1445-8.
• Article: A mitochondria-targeted inhibitor of cytochrome c peroxidase mitigates radiation-induced death.

  Jeffrey Atkinson, Alexandr A Kapralov, Naveena Yanamala, Yulia Y Tyurina, Andrew A Amoscato, Linda Pearce, Jim Peterson, Zhentai Huang, Jianfei Jiang, Alejandro K Samhan-Arias, [......], Jackie Fletcher, Yongsheng Wang, Irina I Vlasova, Judith Klein-Seetharaman, Detcho A Stoyanovsky, Hülya Bayîr, Bruce R Pitt, Michael W Epperly, Joel S Greenberger, Valerian E Kagan
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  ABSTRACT: The risk of radionuclide release in terrorist acts or exposure of healthy tissue during radiotherapy demand potent radioprotectants/radiomitigators. Ionizing radiation induces cell death by initiating the selective peroxidation of cardiolipin in mitochondria by the peroxidase activity of its complex with cytochrome c leading to release of haemoprotein into the cytosol and commitment to the apoptotic program. Here we design and synthesize mitochondria-targeted triphenylphosphonium-conjugated imidazole-substituted oleic and stearic acids that blocked peroxidase activity of cytochrome c/cardiolipin complex by specifically binding to its haem-iron. We show that both compounds inhibit pro-apoptotic oxidative events, suppress cyt c release, prevent cell death, and protect mice against lethal doses of irradiation. Significant radioprotective/radiomitigative effects of imidazole-substituted oleic acid are observed after pretreatment of mice from 1 h before through 24 h after the irradiation.
  Nature Communications 01/2011; 2:497. · 7.40 Impact Factor
• Article: Fantastic voyage and opportunities of engineered nanomaterials: what are the potential risks of occupational exposures?

  Valerian E Kagan, Jingwen Shi, Weihong Feng, Anna A Shvedova, Bengt Fadeel
  Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine 09/2010; 52(9):943-6. · 1.88 Impact Factor
• Source

  Available from: Judith Klein-Seetharaman

  Article: Carbon nanotubes degraded by neutrophil myeloperoxidase induce less pulmonary inflammation.

  Valerian E Kagan, Nagarjun V Konduru, Weihong Feng, Brett L Allen, Jennifer Conroy, Yuri Volkov, Irina I Vlasova, Natalia A Belikova, Naveena Yanamala, Alexander Kapralov, [......], Jingwen Shi, Elena R Kisin, Ashley R Murray, Jonathan Franks, Donna Stolz, Pingping Gou, Judith Klein-Seetharaman, Bengt Fadeel, Alexander Star, Anna A Shvedova
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  ABSTRACT: We have shown previously that single-walled carbon nanotubes can be catalytically biodegraded over several weeks by the plant-derived enzyme, horseradish peroxidase. However, whether peroxidase intermediates generated inside human cells or biofluids are involved in the biodegradation of carbon nanotubes has not been explored. Here, we show that hypochlorite and reactive radical intermediates of the human neutrophil enzyme myeloperoxidase catalyse the biodegradation of single-walled carbon nanotubes in vitro, in neutrophils and to a lesser degree in macrophages. Molecular modelling suggests that interactions of basic amino acids of the enzyme with the carboxyls on the carbon nanotubes position the nanotubes near the catalytic site. Importantly, the biodegraded nanotubes do not generate an inflammatory response when aspirated into the lungs of mice. Our findings suggest that the extent to which carbon nanotubes are biodegraded may be a major determinant of the scale and severity of the associated inflammatory responses in exposed individuals.
  Nature Nanotechnology 04/2010; 5(5):354-9. · 27.27 Impact Factor
• Article: [Assay of evodin, evodiamine and rutaecarpine in Fructus Evodiae by QAMS].

  Yafang Song, Zhimin Wang, Jingjing Zhu, Lihua Yan, Qiwei Zhang, Muxin Gong, Huimin Gao, Weihong Feng, Weihao Wang
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  ABSTRACT: To develop a Quantitative Assay of Multi-components by Single - marker (QAMS) for simultaneous determination of three components in Fructus Evodiae, and examine the feasibility of using the relative correction factors between the different types of compounds. Rutaecarpine was selected as the internal reference substance; the relative correction factors of evodin and evodiamine were calculated. The contents of three components in 11 batches of samples were determined by both external standard method and QAMS. The validity of the QAMS method was evaluated by comparison of their quantitative results. No obvious differences (RSD < 5%) were found in the quantitative results of evodin and evodiamine in 11 batches of Fructus Evodiae determined by the two methods. It is feasible and suitable to determine evodin and evodiamine in Fructus Evodiae by QAMS, and this method can be used for a certain different types of compounds.
  Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 11/2009; 34(21):2781-5.
• Article: Peroxidase activity of hemoglobin-haptoglobin complexes: covalent aggregation and oxidative stress in plasma and macrophages.

  Alexandr Kapralov, Irina I Vlasova, Weihong Feng, Akihiro Maeda, Karen Walson, Vladimir A Tyurin, Zhentai Huang, Rajesh K Aneja, Joseph Carcillo, Hülya Bayir, Valerian E Kagan
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  ABSTRACT: As a hemoprotein, hemoglobin (Hb) can, in the presence of H(2)O(2), act as a peroxidase. In red blood cells, this activity is regulated by the reducing environment. For stroma-free Hb this regulation is lost, and the potential for Hb to become a peroxidase is high and further increased by inflammatory cells generating superoxide. The latter can be converted into H(2)O(2) and feed Hb peroxidase activity. Haptoglobins (Hp) bind with extracellular Hb and reportedly weaken Hb peroxidase activity. Here we demonstrate that: (i) Hb peroxidase activity is retained upon binding with Hp; (ii) in the presence of H(2)O(2), Hb-Hp peroxidase complexes undergo covalent cross-linking; (iii) peroxidase activity of Hb-Hp complexes and aggregates consumes reductants such as ascorbate and nitric oxide; (iv) cross-linked Hb-Hp aggregates are taken up by macrophages at rates exceeding those for noncovalently cross-linked Hb-Hp complexes; (v) the engulfed Hb-Hp aggregates activate superoxide production and induce intracellular oxidative stress (deplete endogenous glutathione and stimulate lipid peroxidation); (vi) Hb-Hp aggregates cause cytotoxicity to macrophages; and (vii) Hb-Hp aggregates are present in septic plasma. Overall, our data suggest that under conditions of severe inflammation and oxidative stress, peroxidase activity of Hb-Hp covalent aggregates may cause macrophage dysfunction and microvascular vasoconstriction, which are commonly seen in severe sepsis and hemolytic diseases.
  Journal of Biological Chemistry 10/2009; 284(44):30395-407. · 4.77 Impact Factor
• Source

  Available from: PubMed Central

  Article: Phosphatidylserine targets single-walled carbon nanotubes to professional phagocytes in vitro and in vivo.

  Nagarjun V Konduru, Yulia Y Tyurina, Weihong Feng, Liana V Basova, Natalia A Belikova, Hülya Bayir, Katherine Clark, Marc Rubin, Donna Stolz, Helen Vallhov, Annika Scheynius, Erika Witasp, Bengt Fadeel, Padmakar D Kichambare, Alexander Star, Elena R Kisin, Ashley R Murray, Anna A Shvedova, Valerian E Kagan
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  ABSTRACT: Broad applications of single-walled carbon nanotubes (SWCNT) dictate the necessity to better understand their health effects. Poor recognition of non-functionalized SWCNT by phagocytes is prohibitive towards controlling their biological action. We report that SWCNT coating with a phospholipid "eat-me" signal, phosphatidylserine (PS), makes them recognizable in vitro by different phagocytic cells - murine RAW264.7 macrophages, primary monocyte-derived human macrophages, dendritic cells, and rat brain microglia. Macrophage uptake of PS-coated nanotubes was suppressed by the PS-binding protein, Annexin V, and endocytosis inhibitors, and changed the pattern of pro- and anti-inflammatory cytokine secretion. Loading of PS-coated SWCNT with pro-apoptotic cargo (cytochrome c) allowed for the targeted killing of RAW264.7 macrophages. In vivo aspiration of PS-coated SWCNT stimulated their uptake by lung alveolar macrophages in mice. Thus, PS-coating can be utilized for targeted delivery of SWCNT with specified cargoes into professional phagocytes, hence for therapeutic regulation of specific populations of immune-competent cells.
  PLoS ONE 02/2009; 4(2):e4398. · 4.09 Impact Factor
• Article: Mass-spectrometric characterization of phospholipids and their primary peroxidation products in rat cortical neurons during staurosporine-induced apoptosis.

  Vladimir A Tyurin, Yulia Y Tyurina, Weihong Feng, Alexandra Mnuskin, Jianfei Jiang, Minke Tang, Xiaojing Zhang, Qing Zhao, Patrick M Kochanek, Robert S B Clark, Hülya Bayir, Valerian E Kagan
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  ABSTRACT: The molecular diversity of phospholipids is essential for their structural and signaling functions in cell membranes. In the current work, we present, the results of mass spectrometric characterization of individual molecular species in major classes of phospholipids -- phosphatidylcholine (PtdCho), phosphatidylethanolamine (PtdEtn), phosphatidylserine (PtdSer), phosphatidylinositol (PtdIns), sphingomyelin (CerPCho), and cardiolipin (Ptd(2)Gro) -- and their oxidation products during apoptosis induced in neurons by staurosporine (STS). The diversity of molecular species of phospholipids in rat cortical neurons followed the order Ptd(2)Gro > PtdEtn > PtdCho > PtdSer > PtdIns > CerPCho. The number of polyunsaturated oxidizable species decreased in the order Ptd(2)Gro > PtdEtn > PtdCho > PtdSer > PtdIns > CerPCho. Thus a relatively minor class of phospholipids, Ptd(2)Gro, was represented in cortical neurons by the greatest variety of both total and peroxidizable molecular species. Quantitative fluorescence HPLC analysis employed to assess the oxidation of different classes of phospholipids in neuronal cells during intrinsic apoptosis induced by STS revealed that three anionic phospholipids -- Ptd(2)Gro > PtdSer > PtdIns -- underwent robust oxidation. No significant oxidation in the most dominant phospholipid classes -- PtdCho and PtdEtn -- was detected. MS-studies revealed the presence of hydroxy-, hydroperoxy- as well as hydroxy-/hydroperoxy-species of Ptd(2)Gro, PtdSer, and PtdIns. Experiments in model systems where total cortex Ptd(2)Gro and PtdSer fractions were incubated in the presence of cytochrome c (cyt c) and H(2)O(2), confirmed that molecular identities of the products formed were similar to the ones generated during STS-induced neuronal apoptosis. The temporal sequence of biomarkers of STS-induced apoptosis and phospholipid peroxidation combined with recently demonstrated redox catalytic properties of cyt c realized through its interactions with Ptd(2)Gro and PtdSer suggest that cyt c acts as a catalyst of selective peroxidation of anionic phospholipids yielding Ptd(2)Gro and PtdSer peroxidation products. These oxidation products participate in mitochondrial membrane permeability transition and in PtdSer externalization leading to recognition and uptake of apoptotic cells by professional phagocytes.
  Journal of Neurochemistry 11/2008; 107(6):1614-33. · 4.06 Impact Factor
• Article: Cardiolipin deficiency leads to decreased cardiolipin peroxidation and increased resistance of cells to apoptosis.

  Zhentai Huang, Jianfei Jiang, Vladimir A Tyurin, Qing Zhao, Alexandra Mnuskin, Jin Ren, Natalia A Belikova, Weihong Feng, Igor V Kurnikov, Valerian E Kagan
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  ABSTRACT: Cardiolipin (CL), a unique mitochondrial phospholipid synthesized by CL synthase (CLS), plays important, yet not fully understood, roles in mitochondria-dependent apoptosis. We manipulated CL levels in HeLa cells by knocking down CLS using RNA interference and selected a clone of CL-deficient cells with approximately 45% of its normal content. ESI-MS analysis showed that the CL molecular species were the same in CL-deficient and CL-sufficient cells. CL deficiency did not change mitochondrial functions (membrane potential, reactive oxygen species generation, cellular ATP levels) but conferred resistance to apoptosis induced by actinomycin D (ActD), rotenone, or gamma-irradiation. During ActD-induced apoptosis, decreased CL peroxidation along with suppressed cytochrome (cyt) c release was observed in CL-deficient cells, whereas Bax translocation to mitochondria remained similar to that in CL-sufficient HeLa cells. The amounts of loosely bound cyt c (releasable under high ionic strength conditions) were the same in CL-deficient and CL-sufficient cells. Given that CL peroxidation during apoptosis is catalyzed by CL/cyt c complexes and CL oxidation products are essential for cyt c release from mitochondria, our results suggest that CL deficiency prevents adequate assembly of productive CL/cyt c complexes and CL peroxidation, resulting in increased resistance to apoptosis.
  Free Radical Biology and Medicine 07/2008; 44(11):1935-44. · 5.42 Impact Factor
• Article: Interplay between bax, reactive oxygen species production, and cardiolipin oxidation during apoptosis.

  Jianfei Jiang, Zhentai Huang, Qing Zhao, Weihong Feng, Natalia A Belikova, Valerian E Kagan
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  ABSTRACT: Bax/Bak activation and cardiolipin peroxidation are essential for cytochrome c release during apoptosis, yet, the link between them remains elusive. We report that sequence of events after exposure of mouse embryonic fibroblast (MEF) cells to actinomycin D followed the order: Bax translocation-->superoxide production-->cardiolipin peroxidation. Genetic ablation of Bax/Bak inhibited actinomycin D induced superoxide production and cardiolipin peroxidation. Rotenone caused robust superoxide generation but did not trigger cardiolipin peroxidation in Bax/Bak double knockout MEF cells. This suggests that, in addition to participating in ROS generation, Bax/Bak play another specific role in cardiolipin oxidation. In isolated mitochondria, recombinant Bax enhanced succinate induced cardiolipin oxidation and cytochrome c release. Mitochondrial peroxidase activity, likely involved in cardiolipin peroxidation, was enhanced upon incubation with recombinant Bax. Thus, cardiolipin peroxidation may be causatively and time-dependently related to Bax/Bak effects on ROS generation and peroxidase activation of cytochrome c.
  Biochemical and Biophysical Research Communications 03/2008; 368(1):145-50. · 2.48 Impact Factor
• Article: Salvianolic acid B improves motor function after cerebral ischemia in rats.

  Minke Tang, Weihong Feng, Yan Zhang, Jing Zhong, Juntian Zhang
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  ABSTRACT: In a previous short-term study, salvianolic acid B was reported to have a protective effect on cerebral ischemia. Here, we investigated whether salvianolic acid B improves the recovery of motor function after cerebral ischemia in a 14-day investigation. Cerebral ischemia was induced by middle cerebral artery occlusion in rats. Motor function was evaluated with beam-walking performance. Neural cell injury in both the sensorimotor cortex and CA1 of the hippocampus ipsilateral to ischemia was studied by Nissl stain with methylene blue. The integrity of cerebral microvessels was monitored by immunoglobulin extravasations. Neurogenesis in the subgranular zone in the dentate gyrus of the hippocampus was detected with 5'-bromo-2'-deoxyuridine incorporation. Animals receiving salvianolic acid B at a dose of 10 mg/kg had a more rapid recovery of beam-walking performance than vehicle-treated ischemia animals, and the improvement became significant at 10 and 14 days after ischemia (P<0.05). Treatment with salvianolic acid B at a dose of 10 mg/kg also significantly prevented neural cell loss in CA1 of the hippocampus. Neural cells in the sensorimotor cortex were also preserved in animals that received salvianolic acid B at a high dose of 10 mg/kg. Salvianolic acid B (10 mg/kg) also improved the integrity of microvessels after ischemia. We observed a slight increase in 5'-bromo-2'-deoxyuridine-positive cells in the subgranular zone of the hippocampus in the animals treated with salvianolic acid B at a dose of 10 mg/kg. These data indicate that salvianolic acid B could improve the recovery of motor function after cerebral ischemia in rats.
  Behavioural Pharmacology 10/2006; 17(5-6):493-8. · 2.72 Impact Factor
• Article: Pharmacological study of the novel compound FLZ against experimental Parkinson's models and its active mechanism.

  Weihong Feng, Huailing Wei, Geng Tao Liu
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  ABSTRACT: FLZ is a synthetic new derivative of squamosamide. Pharmacological study found that FLZ given orally improved the abnormal behavior caused by the functional disturbance of dopaminergic and cholinergic neurons in mice. FLZ significantly increased the content of dopamine and its metabolites in striatum in MPTP model mice. FLZ also remarkably protected dopaminergic PC-12 cells against dopamine and MPP+ induced injury and apoptosis in vitro. The compound inhibited the formation of dopamine-melanin and protein polymers. Additionally, FLZ inhibited cytochrome-c release from mitochondria and caspase-3 activation by dopamine in PC-12 cells. The above results suggest that compound FLZ possesses anti-PD activity through neuroprotection.
  Molecular Neurobiology 02/2005; 31(1-3):295-300. · 5.74 Impact Factor
• Article: Correction: Phosphatidylserine Targets Single-Walled Carbon Nanotubes to Professional Phagocytes In Vitro and In Vivo

  Nagarjun V Konduru, Yulia Y Tyurina, Weihong Feng, Liana V Basova, Natalia A Belikova, Hülya Bayir, Katherine Clark, Marc Rubin, Donna Stolz, Helen Vallhov, Annika Scheynius, Erika Witasp, Bengt Fadeel, Padmakar D Kichambare, Alexander Star, Elena R Kisin, Ashley R Murray, Anna A Shvedova, Valerian E Kagan