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1.
Ann Rheum Dis ; 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788494

RESUMO

OBJECTIVES: S100A9, an alarmin that can form calprotectin (CP) heterodimers with S100A8, is mainly produced by keratinocytes and innate immune cells. The contribution of keratinocyte-derived S100A9 to psoriasis (Ps) and psoriatic arthritis (PsA) was evaluated using mouse models, and the potential usefulness of S100A9 as a Ps/PsA biomarker was assessed in patient samples. METHODS: Conditional S100A9 mice were crossed with DKO* mice, an established psoriasis-like mouse model based on inducible epidermal deletion of c-Jun and JunB to achieve additional epidermal deletion of S100A9 (TKO* mice). Psoriatic skin and joint disease were evaluated in DKO* and TKO* by histology, microCT, RNA and proteomic analyses. Furthermore, S100A9 expression was analysed in skin, serum and synovial fluid samples of patients with Ps and PsA. RESULTS: Compared with DKO* littermates, TKO* mice displayed enhanced skin disease severity, PsA incidence and neutrophil infiltration. Altered epidermal expression of selective pro-inflammatory genes and pathways, increased epidermal phosphorylation of STAT3 and higher circulating TNFα were observed in TKO* mice. In humans, synovial S100A9 levels were higher than the respective serum levels. Importantly, patients with PsA had significantly higher serum concentrations of S100A9, CP, VEGF, IL-6 and TNFα compared with patients with only Ps, but only S100A9 and CP could efficiently discriminate healthy individuals, patients with Ps and patients with PsA. CONCLUSIONS: Keratinocyte-derived S100A9 plays a regulatory role in psoriatic skin and joint disease. In humans, S100A9/CP is a promising marker that could help in identifying patients with Ps at risk of developing PsA.

2.
Protein Expr Purif ; 189: 105989, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626801

RESUMO

Complications related to atherosclerosis account for approximately 1 in 4 deaths in the United States and treatment has focused on lowering serum LDL-cholesterol levels with statins. However, approximately 50% of those diagnosed with atherosclerosis have blood cholesterol levels within normal parameters. Human fortilin is an anti-apoptotic protein and a factor in macrophage-mediated atherosclerosis and is hypothesized to protect inflammatory macrophages from apoptosis, leading to subsequent cardiac pathogenesis. Fortilin is unique because it provides a novel drug target for atherosclerosis that goes beyond lowering cholesterol and utilization of a solution nuclear magnetic resonance (NMR) spectroscopy, structure-based drug discovery approach requires milligram quantities of pure, bioactive, recombinant fortilin. Here, we designed expression constructs with different affinity tags and protease cleavage sites to find optimal conditions to obtain the quantity and purity of protein necessary for structure activity relationship studies. Plasmids encoding fortilin with maltose binding protein (MBP), 6-histidine (6His) and glutathione-S-transferase (GST), N- terminal affinity tags were expressed and purified from Escherichia coli (E. coli). Cleavage sites with tobacco etch virus (TEV) protease and human rhinovirus (HRV) 3C protease were assessed. Despite high levels of expression of soluble protein, the fusion constructs were resistant to proteinases without the inclusion of amino acids between the cleavage site and N-terminus. We surveyed constructs with increasing lengths of glycine/serine (GGS) linkers between the cleavage site and fortilin and found that inclusion of at least one GGS insert led to successful protease cleavage and pure fortilin with conserved binding to calcium as measured by NMR.


Assuntos
Cálcio/química , Proteínas Recombinantes de Fusão/genética , Proteína Tumoral 1 Controlada por Tradução/genética , Proteases Virais 3C/química , Sítios de Ligação , Cálcio/metabolismo , Clonagem Molecular , Endopeptidases/química , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Histidina/genética , Histidina/metabolismo , Humanos , Proteínas Ligantes de Maltose/genética , Proteínas Ligantes de Maltose/metabolismo , Modelos Moleculares , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteólise , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Proteína Tumoral 1 Controlada por Tradução/química , Proteína Tumoral 1 Controlada por Tradução/metabolismo
3.
Int J Mol Sci ; 22(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207917

RESUMO

Osteoarthritis is a major concern in the United States and worldwide. Current non-surgical and surgical approaches alleviate pain but show little evidence of cartilage restoration. Cell-based treatments may hold promise for the regeneration of hyaline cartilage-like tissue at the site of injury or wear. Cell-cell and cell-matrix interactions have been shown to drive cell differentiation pathways. Biomaterials for clinically relevant applications can be generated from decellularized porcine auricular cartilage. This material may represent a suitable scaffold on which to seed and grow chondrocytes to create new cartilage. In this study, we used decellularization techniques to create an extracellular matrix scaffold that supports chondrocyte cell attachment and growth in tissue culture conditions. Results presented here evaluate the decellularization process histologically and molecularly. We identified new and novel biomarker profiles that may aid future cartilage decellularization efforts. Additionally, the resulting scaffold was characterized using scanning electron microscopy, fluorescence microscopy, and proteomics. Cellular response to the decellularized scaffold was evaluated by quantitative real-time PCR for gene expression analysis.


Assuntos
Diferenciação Celular , Condrogênese , Cartilagem da Orelha/química , Matriz Extracelular/química , Teste de Materiais , Alicerces Teciduais/química , Animais , Linhagem Celular , Humanos , Suínos
4.
Int J Mol Sci ; 21(6)2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32244989

RESUMO

The Center of Biomedical Research Excellence in Matrix Biology strives to improve our understanding of extracellular matrix at molecular, cellular, tissue, and organismal levels to generate new knowledge about pathophysiology, normal development, and regenerative medicine. The primary goals of the Center are to i) support junior investigators, ii) enhance the productivity of established scientists, iii) facilitate collaboration between both junior and established researchers, and iv) build biomedical research infrastructure that will support research relevant to cell-matrix interactions in disease progression, tissue repair and regeneration, and v) provide access to instrumentation and technical support. A Pilot Project program provides funding to investigators who propose applying their expertise to matrix biology questions. Support from the National Institute of General Medical Sciences at the National Institutes of Health that established the Center of Biomedical Research Excellence in Matrix Biology has significantly enhanced the infrastructure and the capabilities of researchers at Boise State University, leading to new approaches that address disease diagnosis, prevention, and treatment. New multidisciplinary collaborations have been formed with investigators who may not have previously considered how their biomedical research programs addressed fundamental and applied questions involving the extracellular matrix. Collaborations with the broader matrix biology community are encouraged.


Assuntos
Pesquisa Biomédica , Comportamento Cooperativo , Matriz Extracelular/metabolismo , Pesquisadores , Comitês Consultivos , Escolha da Profissão , Humanos , Estudantes
5.
Protein Expr Purif ; 134: 147-153, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28400296

RESUMO

The RNA-binding proteins that comprise the La-related protein (LARP) superfamily have been implicated in a wide range of cellular functions, from tRNA maturation to regulation of protein synthesis. To more expansively characterize the biological function of the LARP6 subfamily, we have recombinantly expressed the full-length LARP6 proteins from two teleost fish, platyfish (Xiphophorus maculatus) and zebrafish (Danio rerio). The yields of the recombinant proteins were enhanced to >2 mg/L using a tandem approach of an N-terminal His6-SUMO tag and an iterative solubility screening assay to identify structurally stabilizing buffer components. The domain topologies of the purified fish proteins were probed with limited proteolysis. The fish proteins contain an internal, protease-resistant 40 kDa domain, which is considerably more stable than the comparable domain from the human LARP6 protein. The fish proteins are therefore a lucrative model system in which to study both the evolutionary divergence of this family of La-related proteins and the structure and conformational dynamics of the domains that comprise the LARP6 protein.


Assuntos
Ciprinodontiformes/genética , Expressão Gênica , Proteínas de Ligação a RNA , Proteínas de Peixe-Zebra , Peixe-Zebra/genética , Animais , Ciprinodontiformes/metabolismo , Humanos , Domínios Proteicos , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/isolamento & purificação
6.
Toxicol Appl Pharmacol ; 311: 42-51, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27693115

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant and high-affinity ligand for the aryl hydrocarbon receptor (AhR). Increasing evidence indicates that AhR signaling contributes to wound healing, which involves the coordinated deposition and remodeling of the extracellular matrix. In the liver, wound healing is attributed to the activation of hepatic stellate cells (HSCs), which mediate fibrogenesis through the production of soluble mediators and collagen type I. We recently reported that TCDD treatment increases the activation of human HSCs in vitro. The goal of this study was to determine how TCDD impacts HSC activation in vivo using a mouse model of experimental liver fibrosis. To elicit fibrosis, C57BL6/male mice were treated twice weekly for 8weeks with 0.5ml/kg carbon tetrachloride (CCl4). TCDD (20µg/kg) or peanut oil (vehicle) was administered once a week during the last 2weeks. Results indicate that TCDD increased liver-body-weight ratios, serum alanine aminotransferase activity, and hepatic necroinflammation in CCl4-treated mice. Likewise, TCDD treatment increased mRNA expression of HSC activation and fibrogenesis genes, namely α-smooth muscle actin, desmin, delta-like homolog-1, TGF-ß1, and collagen type I. However, TCDD treatment did not exacerbate fibrosis, nor did it increase the collagen content of the liver. Instead, TCDD increased hepatic collagenase activity and increased expression of matrix metalloproteinase (MMP)-13 and the matrix regulatory proteins, TIMP-1 and PAI-1. These results support the conclusion that TCDD increases CCl4-induced liver damage and exacerbates HSC activation, yet collagen deposition and the development of fibrosis may be limited by TCDD-mediated changes in extracellular matrix remodeling.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Inflamação/induzido quimicamente , Cirrose Hepática/induzido quimicamente , Dibenzodioxinas Policloradas/toxicidade , Animais , Tetracloreto de Carbono/toxicidade , Colágeno Tipo I/metabolismo , Colagenases/metabolismo , Células Estreladas do Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Índice de Gravidade de Doença
7.
Bioorg Med Chem ; 24(16): 3752-7, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27338657

RESUMO

Veratrum californicum, commonly referred to as corn lily or Californian false hellebore, grows in high mountain meadows and produces the steroidal alkaloid cyclopamine, a potent inhibitor of the Hedgehog (Hh) signaling pathway. The Hh pathway is a crucial regulator of many fundamental processes during vertebrate embryonic development. However, constitutive activation of the Hh pathway contributes to the progression of various cancers. In the present study, a direct correlation was made between the extraction efficiency for cyclopamine from root and rhizome by eight methods, and the associated biological activity in Shh-Light II cells using the Dual-Glo® Luciferase Assay System. Alkaloid recovery ranged from 0.39 to 8.03mg/g, with ethanol soak being determined to be the superior method for obtaining biologically active cyclopamine. Acidic ethanol and supercritical extractions yielded degraded or contaminated cyclopamine with lower antagonistic activity towards Hh signaling.


Assuntos
Alcaloides de Veratrum/farmacologia , Veratrum/química , Biomassa , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/metabolismo , Transdução de Sinais/efeitos dos fármacos , Alcaloides de Veratrum/isolamento & purificação
8.
Environ Toxicol ; 31(12): 1808-1818, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26332274

RESUMO

The induction of oxidative stress and damage appears to be involved in acrylonitrile induction of brain astrocytomas in rat. The present study examined the effects of dietary antioxidant supplementation on acrylonitrile-induced oxidative stress and oxidative damage in rats in vivo. To assess the effects of antioxidants on biomarkers of acrylonitrile-induced oxidative stress, female F344 rats were provided with diets containing vitamin E (0.05%), green tea polyphenols (GTP, 0.4%), N-acetyl cysteine (NAC, 0.3%), sodium selenite (0.1mg/kg), and taurine (10g/kg) for 7 days, and then co-administered with 0 and 100 ppm acrylonitrile in drinking water for 28 days. Significant increase in oxidative DNA damage in brain, evidenced by elevated 8OHdG levels, was seen in acrylonitrile-exposed rats. Supplementation with vitamin E, GTP, and NAC reduced acrylonitrile-induced oxidative DNA damage in brain while no protective effects were seen with the selenium or taurine supplementation. Acrylonitrile increased oxidative DNA damage, measured by the fpg-modified alkaline Comet assay in rat WBCs, which was reduced by supplementation of Vitamin E, GTP, NAC, selenium, and taurine. In addition to stimulation of oxidative DNA damage, acrylonitrile triggered induction of pro-inflammatory cytokines Tnfα, Il-1ß, and Ccl2, and the growth stimulatory cyclin D1 and cyclin D2 genes, which were effectively down-regulated with antioxidant treatment. Antioxidant treatment also was able to stimulate the pro-apoptotic genes Bad, Bax, and FasL and DNA repair genes Xrcc6 and Gadd45α. The results of this study support the involvement of oxidative stress in the development of acrylonitrile-induced astrocytomas and suggest that antioxidants block acrylonitrile-mediated damage through mechanisms that may involve in the suppression of inflammatory responses, inhibition of cell proliferation and stimulation of apoptosis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1808-1818, 2016.


Assuntos
Acrilonitrila/toxicidade , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Carcinógenos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Biomarcadores/metabolismo , Encéfalo/metabolismo , Camellia sinensis/química , Dano ao DNA/efeitos dos fármacos , Suplementos Nutricionais , Feminino , Polifenóis/farmacologia , Ratos Endogâmicos F344 , Selênio/farmacologia , Taurina/farmacologia , Vitamina E/farmacologia
9.
Toxicol Mech Methods ; 26(3): 196-201, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26982377

RESUMO

The Comet assay is a reproducible and sensitive assay for the detection of DNA damage in eukaryotic cells and tissues. Incorporation of lesion specific, oxidative DNA damage repair enzymes (for example, Fpg, OGG1 and EndoIII) in the standard alkaline Comet assay procedure allows for the detection and measurement of oxidative DNA damage. The Comet assay using white blood cells (WBC) has proven useful in monitoring DNA damage from environmental agents in humans. However, it is often impractical to performance Comet assay immediately after blood sampling. Thus, storage of blood sample is required. In this study, we developed and tested a simple storage method for very small amount of whole blood for standard and Fpg-modified modified Comet assay. Whole blood was stored in RPMI 1640 media containing 10% FBS, 10% DMSO and 1 mM deferoxamine at a sample to media ratio of 1:50. Samples were stored at -20 °C and -80 °C for 1, 7, 14 and 28 days. Isolated lymphocytes from the same subjects were also stored under the same conditions for comparison. Direct DNA strand breakage and oxidative DNA damage in WBC and lymphocytes were analyzed using standard and Fpg-modified alkaline Comet assay and compared with freshly analyzed samples. No significant changes in either direct DNA strand breakage or oxidative DNA damage was seen in WBC and lymphocytes stored at -20 °C for 1 and 7 days compared to fresh samples. However, significant increases in both direct and oxidative DNA damage were seen in samples stored at -20 °C for 14 and 28 days. No changes in direct and oxidative DNA damage were observed in WBC and lymphocytes stored at -80 °C for up to 28 days. These results identified the proper storage conditions for storing whole blood or isolated lymphocytes to evaluate direct and oxidative DNA damage using standard and Fpg-modified alkaline Comet assay.


Assuntos
Ensaio Cometa/métodos , Criopreservação/métodos , Dano ao DNA , DNA-Formamidopirimidina Glicosilase , Eritrócitos/patologia , Proteínas de Escherichia coli , Leucócitos/patologia , Adulto , DNA-Formamidopirimidina Glicosilase/isolamento & purificação , Proteínas de Escherichia coli/isolamento & purificação , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade
10.
West N Am Nat ; 75(1): 78-87, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26582971

RESUMO

Sagebrush (Artemisia spp.) in North America is an abundant native plant species that is ecologically and evolutionarily adapted to have a diverse array of biologically active chemicals. Several of these chemicals, specifically polyphenols, have antioxidant activity that may act as biomarkers of biotic or abiotic stress. This study investigated the spatial variation of antioxidant capacity, as well as the relationship between a mammalian herbivore and antioxidant capacity in Wyoming big sagebrush (Artemisia tridentata wyomingensis). We quantified and compared total polyphenols and antioxidant capacity of leaf extracts from sagebrush plants from different spatial scales and at different levels of browsing by a specialist mammalian herbivore, the pygmy rabbit (Brachylagus idahoensis). We found that antioxidant capacity of sagebrush extracts was positively correlated with total polyphenol content. Antioxidant capacity varied spatially within and among plants. Antioxidant capacity in sagebrush was not related to either browsing intensity or duration of association with rabbits. We propose that the patterns of antioxidant capacity observed in sagebrush may be a result of spatial variation in abiotic stress experienced by sagebrush. Antioxidants could therefore provide a biomarker of environmental stress for sagebrush that could aid in management and conservation of this plant in the threatened sagebrush steppe.

11.
Biochemistry ; 53(39): 6231-42, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25215658

RESUMO

The acyl-homoserine lactone (AHL) autoinducer mediated quorum sensing regulates virulence in several pathogenic bacteria. The hallmark of an efficient quorum sensing system relies on the tight specificity in the signal generated by each bacterium. Since AHL signal specificity is derived from the acyl-chain of the acyl-ACP (ACP = acyl carrier protein) substrate, AHL synthase enzymes must recognize and react with the native acyl-ACP with high catalytic efficiency while keeping reaction rates with non-native acyl-ACPs low. The mechanism of acyl-ACP substrate recognition in these enzymes, however, remains elusive. In this study, we investigated differences in catalytic efficiencies for shorter and longer chain acyl-ACP substrates reacting with an octanoyl-homoserine lactone synthase Burkholderia mallei BmaI1. With the exception of two-carbon shorter hexanoyl-ACP, the catalytic efficiencies of butyryl-ACP, decanoyl-ACP, and octanoyl-CoA reacting with BmaI1 decreased by greater than 20-fold compared to the native octanoyl-ACP substrate. Furthermore, we also noticed kinetic cooperativity when BmaI1 reacted with non-native acyl-donor substrates. Our kinetic data suggest that non-native acyl-ACP substrates are unable to form a stable and productive BmaI1·acyl-ACP·SAM ternary complex and are thus effectively discriminated by the enzyme. These results offer insights into the molecular basis of substrate recognition for the BmaI1 enzyme.


Assuntos
Proteína de Transporte de Acila/metabolismo , Acil-Butirolactonas/metabolismo , Proteínas de Bactérias/metabolismo , Ligases/metabolismo , Proteínas de Bactérias/genética , Biocatálise , Burkholderia mallei/enzimologia , Burkholderia mallei/genética , Burkholderia mallei/metabolismo , Cromatografia Líquida de Alta Pressão , Cinética , Ligases/genética , Especificidade por Substrato
12.
Hum Exp Toxicol ; 43: 9603271241231947, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324556

RESUMO

Objectives: Doxorubicin (DOX) is a highly effective chemotherapeutic used to treat many adult and pediatric cancers, such as solid tumors, leukemia, lymphomas and breast cancer. It can also cause injuries to multiple organs, including the heart, liver, and brain or kidney, although cardiotoxicity is the most prominent side effect of DOX. In this study, we examined the potential effects of DOX on autophagy activity in two different mouse fibroblasts.Methods: Mouse embryonic fibroblasts (NIH3T3) and mouse primary cardiac fibroblasts (CFs) were treated with DOX to assess changes in the expression of two commonly used autophagy protein markers, LC3II and p62. We also examined the effects of DOX the on expression of key genes that encode components of the molecular machinery and regulators modulating autophagy in response to both extracellular and intracellular signals.Results: We observed that LC3II levels increased and p62 levels decreased following the DOX treatment in NIH3T3 cells. However, similar effects were not observed in primary cardiac fibroblasts. In addition, DOX treatment induced the upregulation of a significant number of genes involved in autophagy in NIH3T3 cells, but not in primary cardiac fibroblasts.Conclusions: Taken together, these results indicate that DOX upregulates autophagy in fibroblasts in a cell-specific manner.


Assuntos
Estresse Oxidativo , Transdução de Sinais , Humanos , Criança , Animais , Camundongos , Células NIH 3T3 , Fibroblastos , Doxorrubicina/toxicidade , Autofagia , Cardiotoxicidade/metabolismo , Miócitos Cardíacos/metabolismo , Apoptose
13.
BMC Res Notes ; 17(1): 58, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38414083

RESUMO

OBJECTIVES: Osteoarthritis (OA) is a major concern in the United States and worldwide. Development and validation of robust decellularization techniques is critical in generating suitable bioscaffolds for future OA treatment options. DATA DESCRIPTIONS: In the present study, proteins from porcine auricular cartilage before and after decellularization were extracted, digested, and identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The data represents protein profiles of both non-decellularized and decellularized porcine auricular cartilage. This data is intended to be useful to scientists who are interesting in generating biomaterials for potential relevant clinical applications using decellularized cartilage tissue.


Assuntos
Cartilagem da Orelha , Osteoartrite , Suínos , Animais , Proteômica , Cromatografia Líquida , Espectrometria de Massas em Tandem , Engenharia Tecidual/métodos
14.
J Orthop Res ; 42(8): 1870-1879, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38491967

RESUMO

The mechanical resilience of the knee meniscus is provided by a group of structural proteins in the extracellular matrix. Aging can alter the quantity and molecular structure of these proteins making the meniscus more susceptible to debilitating tears. In this study, we determined the effect of aging on the quantity of structural proteins and collagen crosslinks in human lateral meniscus, and examined whether the quantity of these molecules was predictive of tensile toughness (area under the stress-strain curve). Two age groups were tested: a young group under 40 and an older group over 65 years old. Using mass spectrometry, we quantified the abundance of proteins and collagen crosslinks in meniscal tissue that was adjacent to the dumbbell-shaped specimens used to measure uniaxial tensile toughness parallel or perpendicular to the circumferential fiber orientation. We found that the enzymatic collagen crosslink deoxypyridinoline had a significant positive correlation with toughness, and reductions in the quantity of this crosslink with aging were associated with a loss of toughness in the ground substance and fibers. The non-enzymatic collagen crosslink carboxymethyl-lysine increased in quantity with aging, and these increases corresponded to reductions in ground substance toughness. For the collagenous (Types I, II, IV, VI, VIII) and non-collagenous structural proteins (elastin, decorin, biglycan, prolargin) analyzed in this study, only the quantity of collagen VIII was predictive of toughness. This study provides valuable insights on the structure-function relationships of the human meniscus, and how aging causes structural adaptations that weaken the tissue's mechanical integrity.


Assuntos
Envelhecimento , Colágeno , Meniscos Tibiais , Humanos , Idoso , Adulto , Colágeno/metabolismo , Envelhecimento/fisiologia , Masculino , Meniscos Tibiais/metabolismo , Feminino , Pessoa de Meia-Idade , Fenômenos Biomecânicos , Resistência à Tração , Idoso de 80 Anos ou mais , Adulto Jovem
15.
Methods Mol Biol ; 2598: 217-225, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355295

RESUMO

Proteins from hyaline or articular cartilage can be isolated and purified using a series of chemical extraction steps and various identification techniques including mass spectrometry and immunoblotting. The isolation and purification of proteins from cartilage will facilitate the study of specific proteins and multimeric complexes of cartilage proteins to better understand their functions in normal healthy cartilage as well as pathological conditions of cartilage. Cartilage tissue engineering efforts rely on the comprehensive understanding of the composition of cartilage and the function of each of the protein constituents.


Assuntos
Cartilagem Articular , Cartilagem Hialina , Cartilagem Hialina/metabolismo , Cartilagem Articular/metabolismo , Proteoglicanas/metabolismo , Colágeno/metabolismo
16.
Sci Rep ; 13(1): 18944, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919370

RESUMO

Doxorubicin (DOX)-induced cardiotoxicity has been widely observed, yet the specific impact on cardiac fibroblasts is not fully understood. Additionally, the modulation of the transforming growth factor beta (TGF-ß) signaling pathway by DOX remains to be fully elucidated. This study investigated DOX's ability to modulate the expression of genes and proteins involved in the TGF-ß signaling cascade in mouse fibroblasts from two sources by assessing the impact of DOX treatment on TGF-ß inducible expression of pivotal genes and proteins within fibroblasts. Mouse embryonic fibroblasts (NIH3T3) and mouse primary cardiac fibroblasts (CFs) were treated with DOX in the presence of TGF-ß1 to assess changes in protein levels by western blot and changes in mRNA levels by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Our results revealed a dose-dependent reduction in cellular communication network factor 2 (CCN2) protein levels upon DOX treatment in both NIH3T3 and CFs, suggesting an antifibrotic activity by DOX in these fibroblasts. However, DOX only inhibited the TGF-ß1 induced expression of COL1 in NIH3T3 cells but not in CFs. In addition, we observed that DOX treatment reduced the expression of BMP1 in NIH3T3 but not primary cardiac fibroblasts. No significant changes in SMAD2 protein expression and phosphorylation in either cells were observed after DOX treatment. Finally, DOX inhibited the expression of Atf4 gene and increased the expression of Cdkn1a, Id1, Id2, Runx1, Tgfb1, Inhba, Thbs1, Bmp1, and Stat1 genes in NIH3T3 cells but not CFs, indicating the potential for cell-specific responses to DOX and its modulation of the TGF-ß signaling pathway.


Assuntos
Cardiotoxicidade , Fator de Crescimento Transformador beta , Animais , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Cardiotoxicidade/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Células NIH 3T3 , Fibroblastos/metabolismo , Transdução de Sinais , Doxorrubicina/toxicidade , Células Cultivadas
17.
Res Sq ; 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37546862

RESUMO

Doxorubicin (DOX)-induced cardiotoxicity has been widely observed, yet the specific impact on cardiac fibroblasts is not fully understood. Additionally, the modulation of the transforming growth factor beta (TGF-ß) signaling pathway by DOX remains to be fully elucidated. This study investigated DOX's ability to modulate the expression of genes and proteins involved in the TGF-ß signaling cascade in mouse fibroblasts from two sources by assessing the impact of DOX treatment on TGF-ß inducible expression of pivotal genes and proteins within fibroblasts. Mouse embryonic fibroblasts (NIH3T3) and mouse primary cardiac fibroblasts (CFs) were treated with DOX in the presence of TGF-ß1 to assess changes in protein levels by western blot and changes in mRNA levels by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Our results revealed a dose-dependent reduction in cellular communication network factor 2 (CCN2) protein levels upon DOX treatment in both NIH3T3 and CFs. Moreover, we observed that DOX inhibited the TGF-ß1 induced expression of BMP1 in NIH3T3 cells, while BMP1 levels remained high in CFs, and that TGF-ß1 induces the phosphorylation of SMAD2 in both NIH3T3 cells and CFs. While DOX treatment diminished the extent of phosphorylation, the reduction did not reach statistical significance. DOX also inhibited the TGF-ß1 induced expression of COL1 in NIH3T3 cells and CFs. Finally, DOX inhibited the TGF-ß1 induced expression of Atf4 and increased the expression of Cdkn1a, Id1, Id2, Runx1, Tgfb1, Inhba, Thbs1, Bmp1, and Stat1 in NIH3T3 cells but not CFs, indicating the potential for cell-specific responses to DOX and its modulation of the TGF-ß signaling pathway. Understanding the underlying mechanisms of the ability of DOX to modulate gene expression and signaling pathways in fibroblasts holds promise for future development of targeted therapeutic strategies to mitigate DOX-induced cardiotoxicity specifically affecting CFs.

18.
BMC Res Notes ; 16(1): 340, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974221

RESUMO

OBJECTIVE: Doxorubicin (DOX) is a highly effective chemotherapeutic used to treat many adult and pediatric cancers. However, its use is limited due to a dose-dependent cardiotoxicity, which can lead to lethal cardiomyopathy. In contrast to the extensive research efforts on toxic effects of DOX in cardiomyocytes, its effects and mechanisms on cardiac extracellular matrix (ECM) homeostasis and remodeling are poorly understood. In this study, we examined the potential effects of DOX on cardiac ECM to further our mechanistic understanding of DOX-induced cardiotoxicity. RESULTS: DOX-induced significant down-regulation of several ECM related genes in primary cardiac fibroblasts, including Adamts1, Adamts5, Col4a1, Col4a2, Col5a1, Fbln1, Lama2, Mmp11, Mmp14, Postn, and TGFß. Quantitative proteomics analysis revealed significant global changes in the fibroblast proteome following DOX treatment. A pathway analysis using iPathwayGuide of the differentially expressed proteins revealed changes in a list of biological pathways that involve cell adhesion, cytotoxicity, and inflammation. An apparent increase in Picrosirius red staining indicated that DOX-induced an increase in collagen production in cardiac primary fibroblasts after 3-day treatment. No significant changes in collagen organization nor glycoprotein production were observed.


Assuntos
Cardiotoxicidade , Doxorrubicina , Humanos , Criança , Camundongos , Animais , Cardiotoxicidade/metabolismo , Doxorrubicina/farmacologia , Miócitos Cardíacos , Colágeno/metabolismo , Colágeno/farmacologia , Matriz Extracelular/metabolismo , Fibroblastos , Apoptose , Estresse Oxidativo
19.
Clin Toxicol (Phila) ; 60(12): 1309-1317, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36301078

RESUMO

INTRODUCTION: The Veratrum genus is composed of plants containing a diverse set of steroidal alkaloids. Veratrum plant material has been utilized for centuries as herbal medicines, however the alkaloids have such a low therapeutic index that they are not used in modern medicine. Here we report an incident of inadvertent ingestion of V. parviflorum by hikers in Georgia that allowed detection, and in several instances identification of alkaloids from the plant, and correlated their presence within patient blood and breast milk specimens. CASE HISTORY: Eight patients, three male and five female, presented in the spring of 2020 and 2021 with symptoms requiring emergent medical attention after ingestion of Veratrum parviflorum. All patients believed the plants to be a local native species of wild leek, Allium tricoccum, locally known as ramps. Plants were identified using photographs as well as fresh and cooked plant material provided by patients, in consultation with botanists at the University of Georgia Herbarium. Written consent was obtained from all patients for collection of blood and breast milk specimens for laboratory identification of Veratrum alkaloids. METHODS: V. parviflorum plant material, and patient serum and breast milk were analyzed by high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF) to identify steroidal alkaloids. RESULTS: The V. parviflorum extract was confirmed to contain cyclopamine, veratramine, jervine, and muldamine. Two out of the eight patients had detectable concentrations of Veratrum alkaloids. Of the alkaloids identified in the plant, cyclopamine and jervine were detected within patient serum, and cyclopamine and veratramine were observed to be present in breast milk. DISCUSSION: Toxicity resulting from Veratrum steroidal alkaloids has primarily been reported from V. album and V. viride. This is the second report of V. parviflorum poisoning. The present work reports for the first time the presence of muldamine and jervine within V. parviflorum. This work provides the first instance of identification of Veratrum alkaloids in breast milk. Thus, the findings presented herein add to literature record causative agents contributing to the toxicity of V. parviflorum when ingested and potential for secondary poisoning through breastfeeding. CONCLUSION: V. parviflorum toxicity was observed to cause nausea, vomiting, hypotension, bradycardia, abdominal pain, light-headedness, blurred vision, and tingling in the arms. Patients experiencing mild symptoms improved with supportive care, IV fluids, and antiemetics, but hemodynamically unstable patients required atropine and vasopressors. This study demonstrated that more lipophilic Veratrum alkaloids can be passed along in breast milk, which suggests additional precautions may be critical to limit further poisonings.


Assuntos
Alcaloides , Intoxicação por Plantas , Veratrum , Feminino , Humanos , Leite Humano , Alcaloides de Veratrum , Intoxicação por Plantas/tratamento farmacológico
20.
Toxicol Appl Pharmacol ; 254(2): 86-99, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21296097

RESUMO

Reactive oxygen species (ROS) are induced through a variety of endogenous and exogenous sources. Overwhelming of antioxidant and DNA repair mechanisms in the cell by ROS may result in oxidative stress and oxidative damage to the cell. This resulting oxidative stress can damage critical cellular macromolecules and/or modulate gene expression pathways. Cancer induction by chemical and physical agents involves a multi-step process. This process includes multiple molecular and cellular events to transform a normal cell to a malignant neoplastic cell. Oxidative damage resulting from ROS generation can participate in all stages of the cancer process. An association of ROS generation and human cancer induction has been shown. It appears that oxidative stress may both cause as well as modify the cancer process. Recently association between polymorphisms in oxidative DNA repair genes and antioxidant genes (single nucleotide polymorphisms) and human cancer susceptibility has been shown.


Assuntos
Carcinógenos/toxicidade , Dano ao DNA/fisiologia , Neoplasias/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/fisiologia , Humanos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Oxirredução , Estresse Oxidativo/efeitos dos fármacos
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