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Inhibition of metabolic re-programming represents an attractive approach for prevention of prostate cancer. Studies have implicated increased synthesis of fatty acids or glycolysis in pathogenesis of human prostate cancers. We have shown previously that prostate cancer prevention by sulforaphane (SFN) in Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model is associated with inhibition of fatty acid metabolism. This study utilized human prostate cancer cell lines (LNCaP, 22Rv1 and PC-3), two different transgenic mouse models (TRAMP and Hi-Myc) and plasma specimens from a clinical study to explore the glycolysis inhibition potential of SFN. We found that SFN treatment: (i) decreased real-time extracellular acidification rate in LNCaP, but not in PC-3 cell line; (ii) significantly downregulated expression of hexokinase II (HKII), pyruvate kinase M2 and/or lactate dehydrogenase A (LDHA) in vitro in cells and in vivo in neoplastic lesions in the prostate of TRAMP and Hi-Myc mice; and (iii) significantly suppressed glycolysis in prostate of Hi-Myc mice as measured by ex vivo1H magnetic resonance spectroscopy. SFN treatment did not decrease glucose uptake or expression of glucose transporters in cells. Overexpression of c-Myc, but not constitutively active Akt, conferred protection against SFN-mediated downregulation of HKII and LDHA protein expression and suppression of lactate levels. Examination of plasma lactate levels in prostate cancer patients following administration of an SFN-rich broccoli sprout extract failed to show declines in its levels. Additional clinical trials are needed to determine whether SFN treatment can decrease lactate production in human prostate tumors.
Assuntos
Adenocarcinoma/metabolismo , Anticarcinógenos/farmacologia , Glicólise/efeitos dos fármacos , Isotiocianatos/farmacologia , Neoplasias da Próstata/metabolismo , Adenocarcinoma/patologia , Animais , Quimioprevenção/métodos , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias da Próstata/patologia , SulfóxidosRESUMO
The incidence of life-threatening disseminated Candida albicans infections is increasing in hospitalized patients, with fatalities as high as 60%. Death from disseminated candidiasis in a significant percentage of cases is due to fungal invasion of the kidney, leading to renal failure. Treatment of candidiasis is hampered by drug toxicity, the emergence of antifungal drug resistance and lack of vaccines against fungal pathogens. IL-17 is a key mediator of defense against candidiasis. The underlying mechanisms of IL-17-mediated renal immunity have so far been assumed to occur solely through the regulation of antimicrobial mechanisms, particularly activation of neutrophils. Here, we identify an unexpected role for IL-17 in inducing the Kallikrein (Klk)-Kinin System (KKS) in C. albicans-infected kidney, and we show that the KKS provides significant renal protection in candidiasis. Microarray data indicated that Klk1 was upregulated in infected kidney in an IL-17-dependent manner. Overexpression of Klk1 or treatment with bradykinin rescued IL-17RA-/- mice from candidiasis. Therapeutic manipulation of IL-17-KKS pathways restored renal function and prolonged survival by preventing apoptosis of renal cells following C. albicans infection. Furthermore, combining a minimally effective dose of fluconazole with bradykinin markedly improved survival compared to either drug alone. These results indicate that IL-17 not only limits fungal growth in the kidney, but also prevents renal tissue damage and preserves kidney function during disseminated candidiasis through the KKS. Since drugs targeting the KKS are approved clinically, these findings offer potential avenues for the treatment of this fatal nosocomial infection.
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Candidíase/imunologia , Interleucina-17/imunologia , Sistema Calicreína-Cinina/imunologia , Nefropatias/imunologia , Nefropatias/microbiologia , Animais , Western Blotting , Modelos Animais de Doenças , Citometria de Fluxo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The present study is the first to report inhibition of breast cancer cell growth in vitro and in vivo and suppression of self-renewal of breast cancer stem cells (bCSC) by a pine bark component (leelamine). Except for a few recent publications in melanoma, anticancer pharmacology of this interesting phytochemical is largely elusive. Leelamine (LLM) dose-dependently inhibited viability of MDA-MB-231 (triple-negative), MCF-7 (estrogen receptor-positive), and SUM159 (triple-negative) human breast cancer cells in association with apoptotic cell death induction. To the contrary, a normal mammary epithelial cell line derived from fibrocystic breast disease and spontaneously immortalized (MCF-10A) was fully resistant to LLM-mediated cell growth inhibition and apoptosis induction. LLM also inhibited self-renewal of breast cancer stem cells. Apoptosis induction by LLM in breast cancer cells was accompanied by a modest increase in reactive oxygen species production, which was not due to inhibition of mitochondrial electron transport chain complexes. Nevertheless, ectopic expression of manganese superoxide dismutase conferred partial protection against LLM-induced cell death but only at a lower yet pharmacologically relevant concentration. Exposure of breast cancer cells to LLM resulted in (a) induction and/or activation of multidomain proapoptotic proteins Bax and Bak, (b) caspase-9 activation, and (c) cytosolic release of cytochrome c. Bax and Bak deficiency in immortalized fibroblasts conferred significant protection against cell death by LLM. Intraperitoneal administration of LLM (7.5 mg/kg; 5 times/wk) suppressed the growth of orthotopic SUM159 xenografts in mice without any toxicity. In conclusion, the present study provides critical preclinical data to warrant further investigation of LLM. © 2016 Wiley Periodicals, Inc.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Mama/efeitos dos fármacos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Nus , Pinus/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
Ischemic stroke-induced mitochondrial dysfunction in the blood-brain barrier-forming brain endothelial cells (BECs) results in long-term neurological dysfunction post-stroke. We previously reported data from a pilot study where intravenous administration of human BEC (hBEC)-derived mitochondria-containing extracellular vesicles (EVs) showed a potential efficacy signal in a mouse middle cerebral artery occlusion (MCAo) model of stroke. We hypothesized that EVs harvested from donor species homologous to the recipient species (e.g., mouse) may improve therapeutic efficacy, and therefore, use of mouse BEC (mBEC)-derived EVs may improve post-stroke outcomes in MCAo mice. We investigated potential differences in the mitochondria transfer of EVs derived from the same species as the recipient cell (mBEC-EVs and recipient mBECs or hBECs-EVs and recipient hBECs) vs. cross-species EVs and recipient cells (mBEC-EVs and recipient hBECs or vice versa). Our results showed that while both hBEC- and mBEC-EVs transferred EV mitochondria, mBEC-EVs outperformed hBEC-EVs in increasing ATP levels and improved recipient mBEC mitochondrial function via increasing oxygen consumption rates. mBEC-EVs significantly reduced brain infarct volume and neurological deficit scores compared to vehicle-injected MCAo mice. The superior therapeutic efficacy of mBEC-EVs in MCAo mice support the continued use of mBEC-EVs to optimize the therapeutic potential of mitochondria-containing EVs in preclinical mouse models.
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Ischemic stroke-induced mitochondrial dysfunction in the blood-brain barrier-forming brain endothelial cells ( BECs ) results in long-term neurological dysfunction post-stroke. We previously data from a pilot study where intravenous administration of human BEC ( hBEC )-derived mitochondria-containing extracellular vesicles ( EVs ) showed a potential efficacy signal in a mouse middle cerebral artery occlusion ( MCAo ) model of stroke. We hypothesized that EVs harvested from donor species homologous to the recipient species ( e.g., mouse) may improve therapeutic efficacy, and therefore, use of mouse BEC ( mBEC )-derived EVs may improve post-stroke outcomes in MCAo mice. We investigated potential differences in the mitochondria transfer of EVs derived from the same species as the recipient cell (mBEC-EVs and recipient mBECs or hBECs-EVs and recipient hBECs) vs . cross-species EVs and recipient cells (mBEC-EVs and recipient hBECs or vice versa ). Our results showed that while both hBEC- and mBEC-EVs transferred EV mitochondria, mBEC-EVs outperformed hBEC-EVs in increasing ATP levels and improved recipient mBEC mitochondrial function via increasing oxygen consumption rates. mBEC-EVs significantly reduced brain infarct volume and neurological deficit scores compared to vehicle-injected MCAo mice. The superior therapeutic efficacy of mBEC-EVs in a mouse MCAo stroke support the continued use of mBEC-EVs to optimize the therapeutic potential of mitochondria-containing EVs in preclinical mouse models.
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Dicarboxylic fatty acids are generated in the liver and kidney in a minor pathway called fatty acid ω-oxidation. The effects of consuming dicarboxylic fatty acids as an alternative source of dietary fat have not been explored. Here, we fed dodecanedioic acid, a 12-carbon dicarboxylic (DC12), to mice at 20% of daily caloric intake for nine weeks. DC12 increased metabolic rate, reduced body fat, reduced liver fat, and improved glucose tolerance. We observed DC12-specific breakdown products in liver, kidney, muscle, heart, and brain, indicating that oral DC12 escaped first-pass liver metabolism and was utilized by many tissues. In tissues expressing the "a" isoform of acyl-CoA oxidase-1 (ACOX1), a key peroxisomal fatty acid oxidation enzyme, DC12 was chain shortened to the TCA cycle intermediate succinyl-CoA. In tissues with low peroxisomal fatty acid oxidation capacity, DC12 was oxidized by mitochondria. In vitro, DC12 was catabolized even by adipose tissue and was not stored intracellularly. We conclude that DC12 and other dicarboxylic acids may be useful for combatting obesity and for treating metabolic disorders.
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Ischemic stroke causes brain endothelial cell (BEC) death and damages tight junction integrity of the blood-brain barrier (BBB). We harnessed the innate mitochondrial load of BEC-derived extracellular vesicles (EVs) and utilized mixtures of EV/exogenous 27 kDa heat shock protein (HSP27) as a one-two punch strategy to increase BEC survival (via EV mitochondria) and preserve their tight junction integrity (via HSP27 effects). We demonstrated that the medium-to-large (m/lEV) but not small EVs (sEV) transferred their mitochondrial load, that subsequently colocalized with the mitochondrial network of the recipient primary human BECs. Recipient BECs treated with m/lEVs showed increased relative ATP levels and mitochondrial function. To determine if the m/lEV-meditated increase in recipient BEC ATP levels was associated with m/lEV mitochondria, we isolated m/lEVs from donor BECs pre-treated with oligomycin A (OGM, mitochondria electron transport complex V inhibitor), referred to as OGM-m/lEVs. BECs treated with naïve m/lEVs showed a significant increase in ATP levels compared to untreated OGD cells, OGM-m/lEVs treated BECs showed a loss of ATP levels suggesting that the m/lEV-mediated increase in ATP levels is likely a function of their innate mitochondrial load. In contrast, sEV-mediated ATP increases were not affected by inhibition of mitochondrial function in the donor BECs. Intravenously administered m/lEVs showed a reduction in brain infarct sizes compared to vehicle-injected mice in a mouse middle cerebral artery occlusion model of ischemic stroke. We formulated binary mixtures of human recombinant HSP27 protein with EVs: EV/HSP27 and ternary mixtures of HSP27 and EVs with a cationic polymer, poly (ethylene glycol)-b-poly (diethyltriamine): (PEG-DET/HSP27)/EV. (PEG-DET/HSP27)/EV and EV/HSP27 mixtures decreased the paracellular permeability of small and large molecular mass fluorescent tracers in oxygen glucose-deprived primary human BECs. This one-two punch approach to increase BEC metabolic function and tight junction integrity may be a promising strategy for BBB protection and prevention of long-term neurological dysfunction post-ischemic stroke.
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Vesículas Extracelulares , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Humanos , Animais , Proteínas de Choque Térmico HSP27/metabolismo , Encéfalo/metabolismo , Barreira Hematoencefálica/metabolismo , Acidente Vascular Cerebral/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Proteínas de Choque Térmico/metabolismo , AVC Isquêmico/metabolismo , Mitocôndrias/metabolismo , Vesículas Extracelulares/metabolismo , Trifosfato de Adenosina/metabolismoRESUMO
Background: Congenital heart disease (CHD) with single-ventricle (SV) physiology is now survivable with a three-stage surgical course ending with Fontan palliation. However, 10-year transplant-free survival remains at 39-50%, with ventricular dysfunction progressing to heart failure (HF) being a common sequela. For SV-CHD patients who develop HF, undergoing the surgical course would not be helpful and could even be detrimental. As HF risk cannot be predicted and metabolic defects have been observed in Ohia SV-CHD mice, we hypothesized that respiratory defects in peripheral blood mononuclear cells (PBMCs) may allow HF risk stratification in SV-CHD. Methods: SV-CHD (n = 20), biventricular CHD (BV-CHD; n = 16), or healthy control subjects (n = 22) were recruited, and PBMC oxygen consumption rate (OCR) was measured using the Seahorse Analyzer. Respiration was similarly measured in Ohia mouse heart tissue. Results: Post-Fontan SV-CHD patients with HF showed higher maximal respiratory capacity (p = 0.004) and respiratory reserve (p < 0.0001), parameters important for cell stress adaptation, while the opposite was found for those without HF (reserve p = 0.037; maximal p = 0.05). This was observed in comparison to BV-CHD or healthy controls. However, respiration did not differ between SV patients pre- and post-Fontan or between pre- or post-Fontan SV-CHD patients and BV-CHD. Reminiscent of these findings, heart tissue from Ohia mice with SV-CHD also showed higher OCR, while those without CHD showed lower OCR. Conclusion: Elevated mitochondrial respiration in PBMCs is correlated with HF in post-Fontan SV-CHD, suggesting that PBMC respiration may have utility for prognosticating HF risk in SV-CHD. Whether elevated respiration may reflect maladaptation to altered hemodynamics in SV-CHD warrants further investigation.
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We have demonstrated, for the first time that microvesicles, a sub-type of extracellular vesicles (EVs) derived from hCMEC/D3: a human brain endothelial cell (BEC) line transfer polarized mitochondria to recipient BECs in culture and to neurons in mice acute brain cortical and hippocampal slices. This mitochondrial transfer increased ATP levels by 100 to 200-fold (relative to untreated cells) in the recipient BECs exposed to oxygen-glucose deprivation, an in vitro model of cerebral ischemia. We have also demonstrated that transfer of microvesicles, the larger EV fraction, but not exosomes resulted in increased mitochondrial function in hypoxic endothelial cultures. Gene ontology and pathway enrichment analysis of EVs revealed a very high association to glycolysis-related processes. In comparison to heterotypic macrophage-derived EVs, BEC-derived EVs demonstrated a greater selectivity to transfer mitochondria and increase endothelial cell survival under ischemic conditions.
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Micropartículas Derivadas de Células , Vesículas Extracelulares , Animais , Encéfalo , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Camundongos , MitocôndriasRESUMO
Nitric oxide is a strong vasodilatory and anti-inflammatory signaling molecule that plays diverse roles in maintaining vascular homeostasis. Nitric oxide produced by endothelial cells is a critical regulator of this balance, such that endothelial dysfunction is defined as a reduced capacity for nitric oxide production and decreased nitric oxide sensitivity. This ultimately results in an imbalance in vascular homeostasis leading to a prothrombotic, proinflammatory, and less compliant blood vessel wall. Endothelial dysfunction is central in numerous pathophysiologic processes. This article reviews mechanisms governing nitric oxide production and downstream effects, highlighting the role of nitric oxide signaling in organ system pathologies.
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Estado Terminal , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Óxido Nítrico/metabolismo , Animais , Homeostase/fisiologia , Humanos , Espécies Reativas de Oxigênio/metabolismo , VasodilataçãoRESUMO
BACKGROUND: Efficacy of withaferin A (WA), an Ayurvedic medicine constituent, for prevention of mammary cancer and its associated mechanisms were investigated using mouse mammary tumor virus-neu (MMTV-neu) transgenic model. METHODS: Incidence and burden of mammary cancer and pulmonary metastasis were scored in female MMTV-neu mice after 28 weeks of intraperitoneal administration with 100 µg WA (three times/week) (n = 32) or vehicle (n = 29). Mechanisms underlying mammary cancer prevention by WA were investigated by determination of tumor cell proliferation, apoptosis, metabolomics, and proteomics using plasma and/or tumor tissues. Spectrophotometric assays were performed to determine activities of complex III and complex IV. All statistical tests were two-sided. RESULTS: WA administration resulted in a statistically significant decrease in macroscopic mammary tumor size, microscopic mammary tumor area, and the incidence of pulmonary metastasis. For example, the mean area of invasive cancer was lower by 95.14% in the WA treatment group compared with the control group (mean = 3.10 vs 63.77 mm2, respectively; difference = -60.67 mm2; 95% confidence interval = -122.50 to 1.13 mm2; P = .0536). Mammary cancer prevention by WA treatment was associated with increased apoptosis, inhibition of complex III activity, and reduced levels of glycolysis intermediates. Proteomics confirmed downregulation of many glycolysis-related proteins in the tumor of WA-treated mice compared with control, including M2-type pyruvate kinase, phospho glycerate kinase, and fructose-bisphosphate aldolase A isoform 2. CONCLUSIONS: This study reveals suppression of glycolysis in WA-mediated mammary cancer prevention in a clinically relevant mouse model.
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Antineoplásicos/farmacologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/prevenção & controle , Vitanolídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Análise por Conglomerados , Eletroforese em Gel Bidimensional , Feminino , Glicólise/efeitos dos fármacos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/virologia , Vírus do Tumor Mamário do Camundongo , Ayurveda , Camundongos , Camundongos Transgênicos , Distribuição AleatóriaRESUMO
Obesity increases the risk of adverse outcomes during acute critical illnesses such as burns, severe trauma, and acute pancreatitis. Although individuals with more body fat and higher serum cytokines and lipase are more likely to experience problems, the roles that these characteristics play are not clear. We used severe acute pancreatitis as a representative disease to investigate the effects of obesity on local organ function and systemic processes. In obese humans, we found that an increase in the volume of intrapancreatic adipocytes was associated with more extensive pancreatic necrosis during acute pancreatitis and that acute pancreatitis was associated with multisystem organ failure in obese individuals. In vitro studies of pancreatic acinar cells showed that unsaturated fatty acids were proinflammatory, releasing intracellular calcium, inhibiting mitochondrial complexes I and V, and causing necrosis. Saturated fatty acids had no such effects. Inhibition of lipolysis in obese (ob/ob) mice with induced pancreatitis prevented a rise in serum unsaturated fatty acids and prevented renal injury, lung injury, systemic inflammation, hypocalcemia, reduced pancreatic necrosis, and mortality. Thus, therapeutic approaches that target unsaturated fatty acid-mediated lipotoxicity may reduce adverse outcomes in obese patients with critical illnesses such as severe acute pancreatitis.