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1.
Microvasc Res ; 140: 104282, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34813858

RESUMO

The brain microvasculature is altered in normal aging and in the presence of disease processes, such as neurodegeneration or ischemia, but there are few methods for studying living tissues. We now report that viable microvessels (MV) are readily isolated from brain tissue of subjects enrolled in studies of neurodegenerative diseases who undergo rapid autopsy (performed with <12 h postmortem interval - PMI). We find that these MV retain their morphology and cellular components and are fairly uniform in size. Sufficient MV (~3-5000) are obtained from 3 to 4 g of tissue to allow for studies of cellular composition as well as extracellular matrix (ECM). Using live/dead assays, these MV are viable for up to 5 days in tissue culture media (2D) designed to support endothelial cells and up to 11 days post-isolation in a 3-dimensional (3D) matrix (Low Growth Factor Matrigel™). Assays that measure the reducing potential of live cells \demonstrated that the majority of the MV maintain high levels of metabolic activity for a similar number of days as the live/dead assays. Functional cellular components (such as tight junctions and transporter proteins) and ECM of MV in tissue culture media, and to a lesser extent in 3D matrices, were readily visualized using immunofluorescence techniques. MV in tissue culture media are lysed and protein content analyzed, but MV in 3D matrix first require removal of the supporting matrix, which can confound the analysis of MV ECM. Finally, MV can be preserved in cryoprotective media, whereby over 50% retain their baseline viability upon thawing. In summary, we find that MV isolated from human brains undergoing rapid autopsy are viable in standard tissue culture for up to 5 days and the timeframe for experiments can be extended up to 11 days by use of a supportive 3D matrix. Viable human MV allow for temporal and spatial analysis of relevant cellular and ECM components that have implications for microvascular function in neurodegenerative diseases, vascular brain injury, and neurotrauma.


Assuntos
Envelhecimento/patologia , Córtex Cerebral/irrigação sanguínea , Microvasos/patologia , Doenças Neurodegenerativas/patologia , Fatores Etários , Autopsia , Técnicas de Cultura de Células em Três Dimensões , Criopreservação , Meios de Cultura , Matriz Extracelular/patologia , Humanos , Fatores de Tempo , Técnicas de Cultura de Tecidos , Sobrevivência de Tecidos
2.
Anesth Analg ; 123(3): 616-23, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27537755

RESUMO

BACKGROUND: The aged are at increased risk of postoperative wound healing complications. Because local anesthetics are infiltrated commonly into the dermis of surgical wounds, we sought to determine whether local anesthetics adversely affect proliferative and biosynthetic functions of dermal fibroblasts. We also evaluated the effect of local anesthetics on insulin-like growth factor-1 (IGF-1) and transforming growth factor-ß1 (TGF-ß1), growth factors that are important regulators of wound healing. METHODS: Human dermal fibroblasts (HFB) from aged and young donors were exposed to local anesthetic agents at clinically relevant concentrations. We screened the effects of lidocaine, bupivacaine, mepivacaine, and ropivacaine on proliferation of HFB. Lidocaine was most detrimental to proliferation in HFB. We then evaluated the effect of lidocaine on expression and function of the growth factors, IGF-1 and TGF-ß1. Lastly, concurrent exposure to lidocaine and IGF-1 or TGF-ß1 was evaluated for their effects on proliferation and expression of dermal collagens, respectively. RESULTS: Lidocaine and mepivacaine inhibited proliferation in aged HFB (for lidocaine 88% of control, 95% confidence interval [CI], 80%-98%, P = .009 and for mepivacaine 90% of control, 95% CI, 81%-99%, P = .032) but not in young HFB. Ropivacaine and bupivacaine did not inhibit proliferation. Because of the clinical utility of lidocaine relative to mepivacaine, we focused on lidocaine. Lidocaine decreased proliferation in aged HFB, which was abrogated by IGF-1. Lidocaine inhibited transcripts for IGF-1 and insulin-like growth factor-1 receptor (IGF1R) in fibroblasts from aged donors (IGF-1, log2 fold-change -1.25 [42% of control, 95% CI, 19%-92%, P = .035] and IGF1R, log2 fold-change -1.00 [50% of control, 95% CI, 31%-81%, P = .014]). In contrast, lidocaine did not affect the expression of IGF-1 or IGF1R transcripts in the young HFB. Transcripts for collagen III were decreased after lidocaine exposure in aged and young HFB (log2 fold-change -1.28 [41% of control, 95% CI, 20%-83%, P = .022] in aged HFB and log2 fold-change -1.60 [33% of control, 95% CI, 15%-73%, P = .019] in young HFB). Transcripts for collagen I were decreased in aged HFB (log2 fold-change -1.82 [28% of control, 95% CI, 14%-58%, P = .006]) but not in the young HFB. Similar to the transcripts, lidocaine also inhibited the protein expression of collagen III in young and aged HFB (log2 fold-change -1.79 [29% of control, 95% CI, 18%-47%, P = .003] in young HFB and log2 fold-change -1.76 [30% of control, 95% CI, 9%-93%, P = .043] in aged HFB). The effect of lidocaine on the expression of collagen III protein was obviated by TGF-ß1 in both young and aged HFB. CONCLUSIONS: Our results show that lidocaine inhibits processes relevant to dermal repair in aged HFB. The detrimental responses to lidocaine are due, in part, to interactions with IGF-1 and TGF-ß1.


Assuntos
Envelhecimento/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Derme/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Lidocaína/toxicidade , Biossíntese de Proteínas/efeitos dos fármacos , Adulto , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Envelhecimento/fisiologia , Anestésicos Locais/toxicidade , Proliferação de Células/fisiologia , Células Cultivadas , Derme/patologia , Derme/fisiologia , Fibroblastos/patologia , Fibroblastos/fisiologia , Humanos , Masculino , Biossíntese de Proteínas/fisiologia
3.
J Neuroinflammation ; 12: 223, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26608623

RESUMO

BACKGROUND: Disruption of the blood-brain barrier (BBB) occurs in many diseases and is often mediated by inflammatory and neuroimmune mechanisms. Inflammation is well established as a cause of BBB disruption, but many mechanistic questions remain. METHODS: We used lipopolysaccharide (LPS) to induce inflammation and BBB disruption in mice. BBB disruption was measured using (14)C-sucrose and radioactively labeled albumin. Brain cytokine responses were measured using multiplex technology and dependence on cyclooxygenase (COX) and oxidative stress determined by treatments with indomethacin and N-acetylcysteine. Astrocyte and microglia/macrophage responses were measured using brain immunohistochemistry. In vitro studies used Transwell cultures of primary brain endothelial cells co- or tri-cultured with astrocytes and pericytes to measure effects of LPS on transendothelial electrical resistance (TEER), cellular distribution of tight junction proteins, and permeability to (14)C-sucrose and radioactive albumin. RESULTS: In comparison to LPS-induced weight loss, the BBB was relatively resistant to LPS-induced disruption. Disruption occurred only with the highest dose of LPS and was most evident in the frontal cortex, thalamus, pons-medulla, and cerebellum with no disruption in the hypothalamus. The in vitro and in vivo patterns of LPS-induced disruption as measured with (14)C-sucrose, radioactive albumin, and TEER suggested involvement of both paracellular and transcytotic pathways. Disruption as measured with albumin and (14)C-sucrose, but not TEER, was blocked by indomethacin. N-acetylcysteine did not affect disruption. In vivo, the measures of neuroinflammation induced by LPS were mainly not reversed by indomethacin. In vitro, the effects on LPS and indomethacin were not altered when brain endothelial cells (BECs) were cultured with astrocytes or pericytes. CONCLUSIONS: The BBB is relatively resistant to LPS-induced disruption with some brain regions more vulnerable than others. LPS-induced disruption appears is to be dependent on COX but not on oxidative stress. Based on in vivo and in vitro measures of neuroinflammation, it appears that astrocytes, microglia/macrophages, and pericytes play little role in the LPS-mediated disruption of the BBB.


Assuntos
Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/fisiologia , Prostaglandina-Endoperóxido Sintases/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Astrócitos/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/imunologia , Linhagem Celular Transformada , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/imunologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos
4.
Biogerontology ; 15(4): 329-37, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24770843

RESUMO

Skin aging results in increased susceptibility to injury and impaired wound healing. Proliferation of fibroblasts is reduced in aged dermis, which contributes to delays in wound closure. Age-associated differences are regulated, in part, by local or systemic factors such as the IGF-1/IGF1R system. The aim of this study was to determine if expression and activation of IGF1R in aged human dermal fibroblasts, when compared to young fibroblasts, is associated with altered proliferative capacity in a 3D collagen matrix that better simulates the dermal extracellular matrix in vivo. The proliferation of young and aged human dermal fibroblasts in 3D collagen and its association with baseline levels of IGF1R expression were measured. The effect of stimulation and inhibition of Erk phosphorylation on the proliferative capacity of fibroblasts in a 3D collagen matrix was defined. Our results show that proliferation and Erk phosphorylation is reduced in aged dermal fibroblasts relative to young fibroblasts. Activation of Erk phosphorylation in aged fibroblasts is associated with a significant increase in fibroblast proliferation in 3D collagen.


Assuntos
Proliferação de Células , Senescência Celular , Receptor IGF Tipo 1/metabolismo , Pele/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/citologia , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Humanos , Masculino , Fosforilação , Pele/enzimologia , Pele/metabolismo
5.
Wound Repair Regen ; 22(4): 521-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25041621

RESUMO

Age-related changes in the extracellular matrix contribute to delayed wound repair in aging. Hyaluronan, a linear nonsulfated glycosaminoglycan, promotes synthesis and assembly of key extracellular matrix components, such as the interstitial collagens, during wound healing. The biological effects of hyaluronan are mediated, in part, by hyaluronan size. We have previously determined that dermal wounds in aged mice, relative to young mice, have deficits in the generation of lower molecular weight hyaluronan (defined as <300 kDa). Here, we tested the effect of exogenous hyaluronan of 2, 250, or 1,000 kDa sizes on full-thickness excisional wounds in aged mice. Only wounds treated with 250 kDa hyaluronan (HA250) were significantly improved over wounds that received carrier (water) alone. Treatment with HA250 was associated with increased expression of transcripts for the hyaluronan receptors CD44 and RHAMM, as well as collagens III and I. Analyses of dermal protein content by mass spectrometry and Western blotting confirmed significantly increased expression of collagen III in wounds treated with HA250 relative to control wounds. In summary, we find that HA250 improves wound repair and increases the synthesis of collagen III in aged dermal wounds.


Assuntos
Colágeno Tipo III/efeitos dos fármacos , Colágeno Tipo III/metabolismo , Ácido Hialurônico/farmacologia , Lesões dos Tecidos Moles/metabolismo , Cicatrização/efeitos dos fármacos , Envelhecimento/metabolismo , Animais , Western Blotting , Derme/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Receptores de Hialuronatos/efeitos dos fármacos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Lesões dos Tecidos Moles/tratamento farmacológico
6.
bioRxiv ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-37461469

RESUMO

Purpose: Metastatic castration-resistant prostate cancer remains incurable regardless of recent therapeutic advances. Prostate cancer tumors display highly glycolytic phenotypes as the cancer progresses. Non-specific inhibitors of glycolysis have not been utilized successfully for chemotherapy, because of their penchant to cause systemic toxicity. This study reports the preclinical activity, safety, and pharmacokinetics of a novel small molecule preclinical candidate, BKIDC-1553, with antiglycolytic activity. Experimental design: We tested a large battery of prostate cancer cell lines for inhibition of cell proliferation, in vitro. Cell cycle, metabolic and enzymatic assays were used to demonstrate their mechanism of action. A human PDX model implanted in mice and a human organoid were studied for sensitivity to our BKIDC preclinical candidate. A battery of pharmacokinetic experiments, absorption, distribution, metabolism, and excretion experiments, and in vitro and in vivo toxicology experiments were carried out to assess readiness for clinical trials. Results: We demonstrate a new class of small molecule inhibitors where antiglycolytic activity in prostate cancer cell lines is mediated through inhibition of hexokinase 2. These compounds display selective growth inhibition across multiple prostate cancer models. We describe a lead BKIDC-1553 that demonstrates promising activity in a preclinical xenograft model of advanced prostate cancer, equivalent to that of enzalutamide. BKIDC-1553 demonstrates safety and pharmacologic properties consistent with a compound that can be taken into human studies with expectations of a good safety margin and predicted dosing for efficacy. Conclusion: This work supports testing BKIDC-1553 and its derivatives in clinical trials for patients with advanced prostate cancer.

7.
Mol Cancer Ther ; 23(7): 973-994, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507737

RESUMO

Metastatic castration-resistant prostate cancer remains incurable regardless of recent therapeutic advances. Prostate cancer tumors display highly glycolytic phenotypes as the cancer progresses. Nonspecific inhibitors of glycolysis have not been utilized successfully for chemotherapy, because of their penchant to cause systemic toxicity. This study reports the preclinical activity, safety, and pharmacokinetics of a novel small-molecule preclinical candidate, BKIDC-1553, with antiglycolytic activity. We tested a large battery of prostate cancer cell lines for inhibition of cell proliferation, in vitro. Cell-cycle, metabolic, and enzymatic assays were used to demonstrate their mechanism of action. A human patient-derived xenograft model implanted in mice and a human organoid were studied for sensitivity to our BKIDC preclinical candidate. A battery of pharmacokinetic experiments, absorption, distribution, metabolism, and excretion experiments, and in vitro and in vivo toxicology experiments were carried out to assess readiness for clinical trials. We demonstrate a new class of small-molecule inhibitors where antiglycolytic activity in prostate cancer cell lines is mediated through inhibition of hexokinase 2. These compounds display selective growth inhibition across multiple prostate cancer models. We describe a lead BKIDC-1553 that demonstrates promising activity in a preclinical xenograft model of advanced prostate cancer, equivalent to that of enzalutamide. BKIDC-1553 demonstrates safety and pharmacologic properties consistent with a compound that can be taken into human studies with expectations of a good safety margin and predicted dosing for efficacy. This work supports testing BKIDC-1553 and its derivatives in clinical trials for patients with advanced prostate cancer.


Assuntos
Proliferação de Células , Glicólise , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino , Humanos , Animais , Camundongos , Glicólise/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
8.
Fluids Barriers CNS ; 17(1): 60, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993718

RESUMO

BACKGROUND: The microvasculature (MV) of brains with Alzheimer's disease neuropathologic change (ADNC) and cerebral amyloid angiopathy (CAA), in the absence of concurrent pathologies (e.g., infarctions, Lewy bodies), is incompletely understood. OBJECTIVE: To analyze microvascular density, diameter and extracellular matrix (ECM) content in association with ADNC and CAA. METHODS: We examined samples of cerebral cortex and isolated brain microvasculature (MV) from subjects with the National Institute on Aging-Alzheimer's Association (NIA-AA) designations of not-, intermediate-, or high ADNC and from subjects with no CAA and moderate-severe CAA. Cases for all groups were selected with no major (territorial) strokes, ≤ 1 microinfarct in screening sections, and no Lewy body pathology. MV density and diameter were measured from cortical brain sections. Levels of basement membrane (BM) ECM components, the protein product of TNF-stimulated gene-6 (TSG-6), and the ubiquitous glycosaminoglycan hyaluronan (HA) were assayed by western blots or HA ELISA of MV lysates. RESULTS: We found no significant changes in MV density or diameter among any of the groups. Levels of BM laminin and collagen IV (col IV) were lower in MV isolated from the high ADNC vs. not-ADNC groups. In contrast, BM laminin was significantly higher in MV from the moderate-severe CAA vs. the no CAA groups. TSG-6 and HA content were higher in the presence of both high ADNC and CAA, whereas levels of BM fibronectin and perlecan were similar among all groups. CONCLUSIONS: Cortical MV density and diameter are not appreciably altered by ADNC or CAA. TSG-6 and HA are increased in both ADNC and CAA, with laminin and col IV decreased in the BM of high ADNC, but laminin increased in moderate-severe CAA. These results show that changes in the ECM occur in AD and CAA, but independently of one another, and likely reflect on the regional functioning of the brain microvasculature.


Assuntos
Doença de Alzheimer , Membrana Basal , Angiopatia Amiloide Cerebral , Córtex Cerebral , Matriz Extracelular , Microvasos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Membrana Basal/irrigação sanguínea , Membrana Basal/metabolismo , Membrana Basal/patologia , Moléculas de Adesão Celular/metabolismo , Angiopatia Amiloide Cerebral/metabolismo , Angiopatia Amiloide Cerebral/patologia , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Humanos , Ácido Hialurônico/metabolismo , Laminina/metabolismo , Masculino , Microvasos/patologia , Bancos de Tecidos
9.
Tissue Barriers ; 7(4): 1651157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31505997

RESUMO

There is increasing interest in defining the location, content, and role of extracellular matrix (ECM) components in brain structure and function during development, aging, injury, and neurodegeneration. Studies in vivo confirm brain ECM has a dynamic composition with constitutive and induced alterations that impact subsequent cell-cell and cell-matrix interactions. Moreover, it is clear that for any given ECM component, the brain region, and cell type within that location, determines the direction, magnitude, and composition of those changes. This review will examine the ECM at the neurovascular unit (NVU) and the blood-brain barrier (BBB) within the NVU. The discussion will begin at the glycocalyx ECM on the luminal surface of the vasculature, and progress to the abluminal side with a focus on changes in basement membrane ECM during aging and neurodegeneration.


Assuntos
Doença de Alzheimer/genética , Barreira Hematoencefálica/metabolismo , Matriz Extracelular/metabolismo , Envelhecimento , Humanos
10.
Mol Cancer Res ; 17(1): 321-331, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30224545

RESUMO

The incidence of prostate cancer is directly linked to age, but age-associated changes that facilitate prostate cancer development and progression are poorly understood. This study investigated age-related changes in the prostate microenvironment for their influence on prostate cancer behavior. Prostate cancer cells implanted orthotopically into the prostate demonstrated accelerated tumor growth in aged compared with young mice. Metastatic lesions following intravenous injection were also more numerous in aged mice. Tumors from young and aged mice showed no significant differences concerning their proliferation index, apoptosis, or angiogenesis. However, analysis of tumor-infiltrating immune cells by IHC and RNA sequencing (RNA-seq) revealed elevated numbers of macrophages in prostates from aged mice, which are quickly polarized towards a phenotype resembling protumorigenic tumor-associated macrophages upon tumor cell engraftment. Older patients with prostate cancer (>60 years old) in The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA-PRAD) dataset displayed higher expression of macrophage markers (CD163 and VSIG4) which associated with higher rates of biochemical relapse. Remodeling of the collagenous extracellular matrix (ECM) was associated with prostate cancer growth and invasion in the aged microenvironment. Moreover, the collagen matrix extracted from aged mice enhanced the invasiveness and proliferation of prostate cancer cells in vitro. Together, these results demonstrate that the aged prostatic microenvironment can regulate the growth and metastasis of malignant prostate cells, highlighting the role of resident macrophages and their polarization towards a protumorigenic phenotype, along with remodeling of the ECM. IMPLICATIONS: These findings demonstrate the importance of age-associated tumor microenvironment alterations in regulating key aspects of prostate cancer progression.


Assuntos
Células Epiteliais/metabolismo , Neoplasias da Próstata/genética , Animais , Carcinogênese/patologia , Humanos , Masculino , Camundongos , Neoplasias da Próstata/patologia , Microambiente Tumoral
11.
J Alzheimers Dis ; 67(1): 91-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30507579

RESUMO

Little is known about the extracellular matrix (ECM) during progression of AD pathology. Brain ECM is abundant in hyaluronan (HA), a non-sulfated glycosaminoglycan synthesized by HA synthases (HAS) 1-3 in a high molecular weight (MW) form that is degraded into lower MW fragments. We hypothesized that pathologic severity of AD is associated with increases in HA and HA-associated ECM molecules. To test this hypothesis, we assessed HA accumulation and size; HA synthases (HAS) 1-3; and the HA-stabilizing hyaladherin, TSG-6 in parietal cortex samples from autopsied research subjects with not AD (CERAD = 0, Braak = 0- II, n = 12-21), intermediate AD (CERAD = 2, Braak = III-IV, n = 13-18), and high AD (CERAD = 3, Braak = V-VI, n = 32-40) neuropathologic change. By histochemistry, HA was associated with deposits of amyloid and tau, and was also found diffusely in brain parenchyma, with overall HA quantity (measured by ELSA) significantly greater in brains with high AD neuropathology. Mean HA MW was similar among the samples. HAS2 and TSG-6 mRNA expression, and TSG-6 protein levels were significantly increased in high AD and both molecules were present in vasculature, NeuN-positive neurons, and Iba1-positive microglia. These results did not change when accounting for gender, advanced age (≥ 90 years versus <90 years), or the clinical diagnosis of dementia. Collectively, our results indicate a positive correlation between HA accumulation and AD neuropathology, and suggest a possible role for HA synthesis and metabolism in AD progression.


Assuntos
Doença de Alzheimer/patologia , Moléculas de Adesão Celular/análise , Ácido Hialurônico/análise , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Peptídeos beta-Amiloides/análise , Autopsia , Progressão da Doença , Proteínas da Matriz Extracelular/análise , Feminino , Humanos , Masculino , Lobo Parietal/química , RNA Mensageiro/análise , Proteínas tau/análise
12.
J Histochem Cytochem ; 66(10): 697-707, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29782809

RESUMO

The brain changes in volume and composition with normal aging. Cellular components of the brain are supported by an extracellular matrix (ECM) comprised largely of hyaluronan (HA) and HA-associated members of the lectican family of chondroitin sulfate proteoglycans (CSPGs). We examined regional differences in microvascular density, neuronal and glial markers, and accumulation of HA and CSPGs in mouse brains during normal aging. The cortex, hippocampus, dentate gyrus, and cerebellum of young (4 months), middle-aged (14 months), and aged (24-26 months) brains were analyzed. Microvascular density decreased in cerebral cortex and cerebellum with age. There were no detectable differences in neuronal density. There was an increase in astrocytes in the hippocampus with aging. HA accumulation was higher in aged brain relative to young brain in the cerebral cortex and cerebellum, but not in other regions examined. In contrast, CSPGs did not change with aging in any of the brain regions examined. HA and CSPGs colocalized with a subset of neuronal cell bodies and astrocytes, and at the microvasculature. Differences in accumulation of ECM in the aging brain, in the setting of decreased microvascular density and/or increased glial activation, might contribute to age-related regional differences in vulnerability to injury and ischemia.


Assuntos
Envelhecimento , Encéfalo/fisiologia , Encéfalo/ultraestrutura , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Ácido Hialurônico/metabolismo , Animais , Proteoglicanas de Sulfatos de Condroitina/análise , Imunofluorescência/métodos , Hipocampo/fisiologia , Hipocampo/ultraestrutura , Ácido Hialurônico/análise , Processamento de Imagem Assistida por Computador/métodos , Masculino , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/métodos
13.
Drug Healthc Patient Saf ; 9: 105-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29184448

RESUMO

BACKGROUND: Older adults are susceptible to adverse effects from opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), and benzodiazepines (BZDs). We investigated factors associated with the administration of elevated doses of these medications of interest to older adults (≥65 years old) in the emergency department (ED). PATIENTS AND METHODS: ED records were queried for the administration of medications of interest to older adults at two academic medical center EDs over a 6-month period. Frequency of recommended versus elevated ("High doses" were defined as doses that ranged between 1.5 and 3 times higher than the recommended starting doses; "very high doses" were defined as higher than high doses) starting doses of medications, as determined by geriatric pharmacy/medicine guidelines and expert consensus, was compared by age groups (65-69, 70-74, 75-79, 80-84, and ≥85 years), gender, and hospital. RESULTS: There were 17896 visits representing 11374 unique patients >65 years of age (55.3% men, 44.7% women). A total of 3394 doses of medications of interest including 1678 high doses and 684 very high doses were administered to 1364 different patients. Administration of elevated doses of medications was more common than that of recommended doses. Focusing on opioids and BZDs, the 65-69-year age group was much more likely to receive very high doses (1481 and 412 doses, respectively) than the ≥85-year age groups (relative risk [RR] 5.52, 95% CI 2.56-11.90), mainly reflecting elevated opioid dosing (RR 8.28, 95% CI 3.69-18.57). Men were more likely than women to receive very high doses (RR 1.47, 95% CI 1.26-1.72), primarily due to BZDs (RR 2.12, 95% CI 2.07-2.16). CONCLUSION: Administration of elevated doses of opioids and BZDs in the older population occurs frequently in the ED, especially to the 65-69-year age group and men. Further attention to potentially unsafe dosing of high-risk medications to older adults in the ED is warranted.

14.
Drugs Aging ; 34(10): 793-801, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28956283

RESUMO

BACKGROUND: Older adults are more susceptible to adverse events when administered certain medications at doses appropriate for younger adults. OBJECTIVE: The aim of this study was to investigate the effect of default geriatric dosing on computerized physician order entry (CPOE) templates on the subsequent administration of recommended starting doses of opioids, benzodiazepines (BZDs) and non-steroidal anti-inflammatory drugs (NSAIDs) to older adults in the emergency department (ED). METHODS: This was a before-after comparison of the frequency of the recommended starting doses of high-risk medications to adults aged 65 years and older. Computerized records were queried for the administration of the above medication classes in two academic EDs over two similar 4-month periods in 2015 and 2016. Between study periods, the doses of high-risk medications on ED CPOE templates were adjusted for older adults based on established pharmacy guidelines and expert consensus. RESULTS: There was a significant improvement in the rate of recommended dose administration of all medications of interest (27.3 vs. 32.5%, p < 0.001). Not surprisingly, the medications that were maximally impacted were also those most frequently prescribed, with a significant increase in the recommended dosing of opioids (29.0 vs. 35.2%, p < 0.001) accounting for the majority of the change. Although there were no differences in BZDs as a group, there were significant differences in selected BZDs such as midazolam and diazepam. Changes in the recommended dosing of NSAIDs could not be determined due to low numbers of administered doses in both phases of the study. CONCLUSION: Simple changes in the CPOE template resulted in increased administration of the recommended starting doses of high-risk medications to older adults in the ED.


Assuntos
Serviço Hospitalar de Emergência/normas , Sistemas de Registro de Ordens Médicas/normas , Preparações Farmacêuticas/administração & dosagem , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica/normas , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Prescrições de Medicamentos/normas , Feminino , Humanos
15.
J Gerontol A Biol Sci Med Sci ; 72(6): 740-746, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482035

RESUMO

The microvasculature of the aged brain is less dense and more vulnerable to dysfunction than that of the young brain. Brain microvasculature is supported by its surrounding extracellular matrix, which is comprised largely of hyaluronan (HA). HA is continually degraded into lower molecular weight forms that induce neuroinflammation. We examined HA associated with microvessels (MV) of the cerebral cortex of young (4 months), middle-aged (14 months), and aged (24-26 months) mice. We confirmed that the density of cortical MV decreased with age. Perivascular HA levels increased with age, but there was no age-associated change in HA molecular weight profile. MV isolated from aged cortex had more HA than MV from young cortex. Examination of mechanisms that might account for elevated HA levels with aging showed increased HA synthase 2 (HAS2) mRNA and protein in aged MV relative to young MV. In contrast, mRNAs for HA-degrading hyaluronidases or hyaladherins that mitigate HA degradation showed no changes with age. Corresponding to increased HAS2, aged MV synthesized significantly more HA (of all molecular weight classes) in vitro than young MV. We propose that increased HA synthesis and accumulation in brain MV contributes to neuroinflammation and reduced MV density and function in aging.


Assuntos
Envelhecimento/metabolismo , Córtex Cerebral/metabolismo , Ácido Hialurônico/biossíntese , Microvasos/metabolismo , Animais , Córtex Cerebral/irrigação sanguínea , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Expressão Gênica , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Hialuronan Sintases , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Imuno-Histoquímica , Camundongos Endogâmicos C57BL , RNA Mensageiro , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
16.
JAMA Surg ; 152(2): e164604, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28030710

RESUMO

Importance: Assessment of physical frailty in older trauma patients admitted to the intensive care unit is often not feasible using traditional frailty assessment instruments. The use of opportunistic computed tomography (CT) scans to assess sarcopenia and osteopenia as indicators of underlying frailty may provide complementary prognostic information on long-term outcomes. Objective: To determine whether sarcopenia and/or osteopenia are associated with 1-year mortality in an older trauma patient population. Design, Setting, and Participants: A retrospective cohort constructed from a state trauma registry was linked to the statewide death registry and Comprehensive Hospital Abstract Reporting System for readmission data analyses. Admission abdominopelvic CT scans from patients 65 years and older admitted to the intensive care unit of a single level I trauma center between January 2011 and May 2014 were analyzed to identify patients with sarcopenia and/or osteopenia. Patients with a head Injury Severity Score of 3 or greater, an out-of-state address, or inadequate CT imaging or who died within 24 hours of admission were excluded. Exposures: Sarcopenia and/or osteopenia, assessed via total cross-sectional muscle area and bone density at the L3 vertebral level, compared with a group with no sarcopenia or osteopenia. Main Outcomes and Measures: One-year all-cause mortality. Secondary outcomes included 30-day all-cause mortality, 30-day readmission, hospital length of stay, hospital cost, and discharge disposition. Results: Of the 450 patients included in the study, 269 (59.8%) were male and 394 (87.6%) were white. The cohort was split into 4 groups: 74 were retrospectively diagnosed with both sarcopenia and osteopenia, 167 with sarcopenia only, 48 with osteopenia only, and 161 with no radiologic indicators. Among the 408 who survived to discharge, sarcopenia and osteopenia were associated with higher risks of 1-year mortality alone and in combination. After adjustment, the hazard ratio was 9.4 (95% CI, 1.2-75.4; P = .03) for sarcopenia and osteopenia, 10.3 (95% CI, 1.3-78.8; P = .03) for sarcopenia, and 11.9 (95% CI, 1.3-107.4; P = .03) for osteopenia. Conclusions and Relevance: More than half of older trauma patients in this study had sarcopenia, osteopenia, or both. Each factor was independently associated with increased 1-year mortality. Given the prevalent use of abdominopelvic CT in trauma centers, opportunistic screening for radiologic indicators of frailty provides an additional tool for early identification of older trauma patients at high risk for poor outcomes, with the potential for targeted interventions.


Assuntos
Doenças Ósseas Metabólicas/epidemiologia , Causas de Morte , Indicadores Básicos de Saúde , Sarcopenia/epidemiologia , Ferimentos e Lesões/diagnóstico por imagem , Abdome/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/economia , Estudos de Casos e Controles , Feminino , Idoso Fragilizado , Custos Hospitalares/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Alta do Paciente/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Pelve/diagnóstico por imagem , Estudos Retrospectivos , Sarcopenia/diagnóstico por imagem , Sarcopenia/economia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Washington/epidemiologia , Ferimentos e Lesões/economia
17.
In Vitro Cell Dev Biol Anim ; 51(1): 50-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25124870

RESUMO

The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging.


Assuntos
Envelhecimento/fisiologia , Colágeno/farmacologia , Células Epiteliais/patologia , Matriz Extracelular/metabolismo , Ácido Hialurônico/farmacologia , Próstata/patologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Matriz Extracelular/efeitos dos fármacos , Géis/farmacologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
18.
In Vitro Cell Dev Biol Anim ; 49(6): 395-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23661088

RESUMO

Although the incidence of cancer rises with age, tumor growth is often slowed in older hosts. The B16/F10 melanoma cell line is commonly used in murine models of age-related tumor growth suppression. We wished to determine if the growth pattern and gene expression of B16/10 tumors grown in aged mice could be simulated in 3D collagen matrices derived from aged mice. Outcome measures were tumor size in vitro and gene expression of the key growth regulatory molecules: growth hormone receptor (GHR), IL-10Rß, IL-4Rα, and IL-6. B16/F10 tumors were grown in 20-25-mo-old C57/BL6 male mice. Tumor sizes ranged from 30 to 4,910 mg in vivo. Tumors from a subset of mice were removed after euthanasia, and equivalent amounts of each tumor were placed in aged 3D collagen and grown for 5 d. Tumor sizes in aged 3D collagen correlated highly with their original tumor size in vivo. Gene expression changes noted in vivo were also maintained during tumor growth in aged 3D collagen in vitro. The relative expression of GHR was increased, IL-10Rß was unchanged, and IL-4Rα and IL-6 were decreased in the larger tumors relative to the smaller tumors in vitro, in a pattern similar to that noted in vivo. We propose that 3D matrices from aged mice provide an in vitro model of tumor growth that correlates highly with tumor size and expression of key regulatory molecules in vivo.


Assuntos
Envelhecimento/genética , Carcinogênese , Regulação Neoplásica da Expressão Gênica , Melanoma Experimental/metabolismo , Envelhecimento/patologia , Animais , Linhagem Celular Tumoral , Colágeno/química , Humanos , Subunidade beta de Receptor de Interleucina-10/biossíntese , Interleucina-6/biossíntese , Masculino , Melanoma Experimental/genética , Camundongos , Receptores de Superfície Celular/biossíntese , Receptores da Somatotropina/biossíntese
19.
Matrix Biol ; 32(1): 45-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23022999

RESUMO

Changes in extracellular matrix (ECM) are one of many components that contribute to impaired wound healing in aging. This study examined the effect of age on the glycosaminoglycan hyaluronan (HA) in normal and wounded dermis from young (4-6 month-old) and aged (22-24 month-old) mice. HA content and size were similar in the normal dermis of young and aged mice. Dermal explants labeled with [(3)H]-glucosamine showed decreased generation of smaller forms of HA in aged explants relative to young explants. Aged mice exhibited delayed wound repair compared with young mice with the greatest differential at 5 days. Expression of hyaluronan synthase (HAS) 2 and 3, and hyaluronidase (HYAL) 1-3 mRNA in wounds of young and aged mice was similar. There was a trend toward a decreased HYAL protein expression in aged wound dermis, which was accompanied by changes in detectable HYAL activity. Total HA content was similar in young and aged wound dermis. There was significantly less HA in the lower MW range (~250 kDa and smaller) in 5-day wound dermis, but not in 9-day wound dermis, from aged mice relative to young mice. We propose that decreased cleavage of HA is an additional component of impaired dermal wound healing in aging.


Assuntos
Envelhecimento/fisiologia , Derme/metabolismo , Matriz Extracelular/metabolismo , Ácido Hialurônico/metabolismo , Cicatrização/fisiologia , Animais , Ensaio de Imunoadsorção Enzimática , Glucosamina , Glucuronosiltransferase/metabolismo , Técnicas Histológicas , Hialuronan Sintases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trítio
20.
Open Circ Vasc J ; 4: 12-17, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24701258

RESUMO

Models of angiogenesis in vitro are used to study blood vessel morphogenesis and the effects of compounds that influence vascular growth. Herein, we describe techniques to induce angiogenesis-like sprouting from explants of mouse aortae and microvessels cultured in 3-dimensional gels of native type I collagen. The gels are supported by rings of nylon mesh that are sized to fit in 96-well culture plates. This mechanically-supported, miniaturized, 3-dimensional culture system requires only small quantities of cells and reagents and facilitates handling, staining, and imaging by conventional and confocal microscopy.

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