RESUMO
Intercellular adhesion molecule-1 (ICAM-1) is identified as an initiator of neuroinflammatory responses that lead to neurodegeneration and cognitive and sensory-motor deficits in several pathophysiological conditions including traumatic brain injury (TBI). However, the underlying mechanisms of ICAM-1-mediated leukocyte adhesion and transmigration and its link with neuroinflammation and functional deficits following TBI remain elusive. Here, we hypothesize that blocking of ICAM-1 attenuates the transmigration of leukocytes to the brain and promotes functional recovery after TBI. The experimental TBI was induced in vivo by fluid percussion injury (25â psi) in male and female wild-type and ICAM-1-/- mice and in vitro by stretch injury (3â psi) in human brain microvascular endothelial cells (hBMVECs). We treated hBMVECs and animals with ICAM-1 CRISPR/Cas9 and conducted several biochemical analyses and demonstrated that CRISPR/Cas9-mediated ICAM-1 deletion mitigates blood-brain barrier (BBB) damage and leukocyte transmigration to the brain by attenuating the paxillin/focal adhesion kinase (FAK)-dependent Rho GTPase pathway. For analyzing functional outcomes, we used a cohort of behavioral tests that included sensorimotor functions, psychological stress analyses, and spatial memory and learning following TBI. In conclusion, this study could establish the significance of deletion or blocking of ICAM-1 in transforming into a novel preventive approach against the pathophysiology of TBI.
Assuntos
Lesões Encefálicas Traumáticas , Molécula 1 de Adesão Intercelular , Animais , Feminino , Humanos , Masculino , Camundongos , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Sistemas CRISPR-Cas , Células Endoteliais/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Leucócitos , Paxilina , Proteínas rho de Ligação ao GTP/metabolismoRESUMO
BACKGROUND: Diabetic cardiomyopathy (DCM) is one of the severe complications of diabetes with no known biomarkers for early detection. Mitochondria-associated endoplasmic reticulum membranes (MAM) are less studied subcellular targets but an emerging area for exploration in metabolic disorders including DCM. We herein studied the role of MAMs and downstream mitochondrial functions in DCM. We also explored the efficacy of ferulic acid (FeA) against DCM via modulation of MAM and its associated signaling pathway. METHODS: The H9c2 cardiomyoblast cells were incubated with high concentration (33 mM) of d-glucose for 48 h to create a high glucose ambience in vitro. The expression of various critical proteins of MAM, mitochondrial function, oxidative phosphorylation (OxPhos) and the genesis of apoptosis were examined. The rats fed with high fat/high fructose/streptozotocin (single dose, i.p.) were used as a diabetic model and analyzed the insulin resistance and markers of cardiac hypertrophy and apoptosis. RESULTS: High glucose conditions caused the upregulation of MAM formation via PACS2, IP3R2, FUNDC1, and VDAC1 and decreased mitochondrial biogenesis, fusion and OxPhos. The upregulation of mitochondria-driven SMAC-HTRA2-ARTS-XIAP apoptosis and other cell death pathways indicate their critical roles in the genesis of DCM at the molecular level. The diabetic rats also showed cardiomyopathy with increased heart mass index, TNNI3K, troponin, etc. FeA effectively prevented the high glucose-induced MAM alterations and associated cellular anomalies both in vitro and in vivo. CONCLUSION: High glucose-induced MAM distortion and subsequent mitochondrial dysfunctions act as the stem of cardiomyopathy. MAM could be explored as a potential target to treat diabetic cardiomyopathy. Also, the FeA could be an attractive nutraceutical agent for diabetic cardiomyopathy.
Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Animais , Ratos , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Proteínas Reguladoras de Apoptose/uso terapêutico , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/metabolismo , Glucose/toxicidade , Glucose/metabolismo , Proteínas de Membrana , Proteínas Mitocondriais/farmacologia , Miócitos Cardíacos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Canal de Ânion 1 Dependente de Voltagem/uso terapêutico , Mitocôndrias/metabolismo , Retículo Endoplasmático/metabolismoRESUMO
Diabetes-related health issues are increasing day by day in public, and diabetic cardiomyopathy (DCM) is one serious issue among them. There is a lack of proper strategy to control and manage DCM. Here we are attempting a nutraceutical-based approach to protect the heart from DCM. The beneficial effect of cinnamic acid (CiA), was evaluated in an experimental model of diabetes. For this, diabetic model was created by feeding male Wistar rats with a high fat, high fructose diet for 6 months and a single dose of streptozotocin (25 mg/kg bwt). Metformin was used as the positive control. The diabetic rats showed insulin resistance, myocardial injury, and a significant increase of total cholesterol, triglycerides, and LDL. Development of DCM was evident from the increased cardiac mass index, LDH, CKMB, ANP, and CRP levels in the diabetic group. There was a significant increase in the levels of cardiac hypertrophy markers like TGF-ß and ß-MHC in the hearts of diabetic rats revealing DCM. Pro-inflammatory cytokines (TNF-α, IL-6) and lipid peroxides were significantly elevated in the serum of diabetic rats. Histopathology revealed inflammation and necrosis in the heart of diabetic rats confirming DCM. Oral administration of CiA (5 and 10 mg/kg bwt) prevented the development of DCM via its cardioprotective, anti-inflammatory, anti-dyslipidemia potential, and antidiabetic properties. Similarly, metformin (50 mg/kg bwt) has also shown protection against DCM. We conclude from this study that CiA is found to be beneficial against DCM and recommend more detailed preclinical and clinical studies to develop CiA-based nutraceutical against DCM.
Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Metformina , Masculino , Ratos , Animais , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/prevenção & controle , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Ratos Wistar , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Metformina/farmacologia , Metformina/uso terapêuticoRESUMO
Endoplasmic reticulum (ER) and associated signaling pathways are involved in diabetic cardiomyopathy (DCM) however, detailed studies are not available. The present study investigated the role of ER stress and related pathways such as ER-phagy, apoptosis and their underlying mechanisms using appropriate models. Beneficial effect of chlorogenic acid was also evaluated against ER stress mediated DCM. H9c2 cells with high glucose (33 mM, in vitro model of hyperglycemia) showed significant activation of ER stress response (GRP78, PERK, IRE1α, ATF6α) and altered its regulatory proteins (PDI, ERO1α). Also, it enhanced ER-phagy through upregulation of Sec62, RTN3 and downregulation of FAM134B. High glucose caused apoptosis via increased levels of CHOP, caspase 12 and calnexin. All these proteins (PERK, IRE1α, ATF6α, RTN3, Sec62 and FAM134B) have been found to have a significant role in the functioning of heart such as excitation contraction coupling and we expect these alterations to induce cardiomyopathy during diabetes. This was confirmed in in vivo study too. High fat, high fructose diet with mild streptozotocin induced diabetic rats showed an increased expression of BNP confirming cardiac injury. We also noticed severe ER stress in the heart of diabetic animals. All these have contributed significantly into alterations in histopathology and increase of weight of the hearts. These findings clearly show that ER stress plays a vital protagonist in the progression of DCM. We also found chlorogenic acid is effective against hyperglycemia induced pathological alteration both in vitro as well as in vivo.
Assuntos
Ácido Clorogênico/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Retículo Endoplasmático/efeitos dos fármacos , Coração/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/patologia , Cardiomiopatias Diabéticas/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hiperglicemia/tratamento farmacológico , Masculino , Miocárdio/patologia , Ratos Wistar , Transdução de Sinais/efeitos dos fármacosRESUMO
Several mechanisms have been proposed for the heart dysfunction during hyperglycemia. The aim of the present in vitro study is to elucidate the role of alterations in redox homeostasis in the induction of apoptosis during hyperglycemia in H9c2 cells via dysfunction in mitochondria and polyol pathway and evaluation of the beneficial effect of cinnamic acid against the same. The H9c2 cells were incubated with 33â¯mM glucose for 48â¯h to simulate the diabetic condition. Cell injury was confirmed with a significant increase of atrial natriuretic peptide and lactate dehydrogenase release. Alterations in the innate antioxidant system, polyol pathway, mitochondrial integrity, dynamics and apoptosis were investigated. Hyperglycemic insult has significantly affected redox homeostasis via depletion of superoxide dismutase, glutathione and enhanced reactive oxygen species generation. It also caused dysregulation in mitochondrial dynamics (fusion, fission proteins), dissipation of mitochondrial transmembrane potential and increased sorbitol accumulation. Finally, apoptosis was observed with upregulation of Bax, activation of caspase-3 and downregulation of Bcl-2. Cinnamic acid cotreatment increased the innate antioxidant status, improved mitochondrial function and prevented apoptosis in H9c2 cardiomyoblasts. Moreover, this in vitro model is found to be ideal for the elucidation of mechanisms at the cellular and molecular level of any physiological, pharmacological and toxicological incidents in H9c2 cells.
Assuntos
Cinamatos/farmacologia , Hipoglicemiantes/farmacologia , Animais , Fator Natriurético Atrial/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Homeostase/efeitos dos fármacos , Hiperglicemia/metabolismo , L-Lactato Desidrogenase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Oxirredução , Polímeros/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
A series of cardiovascular complications associated with hyperglycemia is a critical threat to the diabetic population. Here we elucidate the link between hyperglycemia and cardiovascular diseases onset, focusing on oxidative stress and associated cardiac dysfunctions. The contribution of advanced glycation end products (AGE) and protein kinase C (PKC) signaling is extensively studied. For induction of hyperglycemia, H9c2 cells were incubated with 33â¯mM glucose for 48â¯h to simulate the diabetic condition in in vitro system. Development of cardiac dysfunction was confirmed with the significant increase of lactate dehydrogenase (LDH) release to the medium and associated decrease in cell viability. Various parameters like free radical generation, alteration in innate antioxidant system, lipid peroxidation, AGE production and PKC α -ERK axis were investigated during hyperglycemia and with chlorogenic acid. Hyperglycemia has significantly enhanced reactive oxygen species (ROS- 4 fold) generation, depleted SOD activity (1.3 fold) and expression of enzymes particularly CuZnSOD (SOD1) and MnSOD (SOD2), increased production of AGE (2.18 fold). Besides, PKC α dependent ERK signaling pathway was found activated (1.43 fold) leading to cardiac dysfunction during hyperglycemia. Chlorogenic acid (CA) was found beneficial against hyperglycemia most probably through its antioxidant mediated activity. The outcome of this preliminary study reveals the importance of integrated approach emphasizing redox status, glycation and signaling pathways like PKC α - ERK axis for control and management of diabetic cardiomyopathy (DCM) and potential of bioactives like CA.
Assuntos
Antioxidantes/farmacologia , Ácido Clorogênico/farmacologia , Glucose/toxicidade , Proteína Quinase C-alfa/biossíntese , Regulação para Cima/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Glicosilação/efeitos dos fármacos , Proteína Quinase C-alfa/antagonistas & inibidores , Ratos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/fisiologiaRESUMO
Insulin resistance (IR) has become a major threat to public health due to its role in metabolic syndrome. Inflammation associated with IR is an interesting area of biomedical research in recent years and is expected to affect insulin signalling pathway via downregulating glucose transporters. In the present study, we evaluate the potential of punicic acid (PA), a nutraceutical found in pomegranate seed oil, against TNF-α induced alteration in 3T3-L1 adipocytes on glucose metabolism, endocrine function and inflammation. IR was induced in 3T3-L1 adipocytes by treating with TNF-α (10 ng/mL) and various concentrations of PA (5, 10, 30 µM) were incubated simultaneously. After 24 h, we found that TNF-α treatment increased mRNA expression of SOCS3, PTP1B and a decrease in IRS1 causing diminished glucose uptake. Further, it showed significantly increased transcriptional activity of NFκB and leptin secretion while PA maintained leptin levels normal. Additionally, PA prevented the over-expression of phosphorylated JNK in a dose dependent manner during IR. PA also ameliorated significantly the upregulation of proinflammatory cytokines. From the results, we conclude that PA is effective to ameliorate TNF-α induced IR and also we recommend the intake of PA for control and management of IR and its associated complications.
Assuntos
Adipócitos/efeitos dos fármacos , Citocinas/metabolismo , Resistência à Insulina , Ácidos Linolênicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Adiponectina/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Sinergismo Farmacológico , Glucose/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Inflamação/metabolismo , Insulina , Proteínas Substratos do Receptor de Insulina/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Leptina/metabolismo , Camundongos , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Fator de Transcrição RelA/metabolismoRESUMO
Obesity leads to inflammation and insulin resistance in adipose tissue. Hypoxia, observed in obese adipose tissue is suggested as a major cause of inflammation and insulin resistance in obesity. However, the role of hypoxia in adipose tissue during obesity and insulin resistance was not well established. Here we mainly explored the crosstalk between hypoxia induced inflammation, and insulin resistance and also secretion of angiogenic factors in 3T3-L1 adipocytes and possible reversal with bilobalide. Hypoxia for 24h significantly (P≤0.05) increased the secretion of MCP-1 (4.59 fold), leptin (2.96 fold) and reduced adiponectin secretion (2.93 fold). In addition, the mRNA level of resistin (6.8 fold) and TLR4 receptors (8.8 fold) was upregulated in hypoxic adipocytes. The release of inflammatory cytokines and expression of TLR4 receptors led to activation of JNK and NF-κB signalling. We further investigated the effects of JNK and NF-κB activation on insulin signalling receptors. The present study showed increased (P≤0.05) serine 307 phosphorylation of IRS-1 (1.9 fold) and decreased expression of IRS-2 (0.53 fold) in hypoxic group showing hypoxia induced impairment in insulin signalling. Hypoxia significantly (P≤0.05) increased basal glucose uptake (3.3 fold) as well as GLUT-1 expression in adipocytes indicating GLUT-1 mediated glucose uptake. Hypoxia for 24h significantly increased (P≤0.05) the expression of angiogenic factors. Bilobalide protected adipocytes from hypoxia induced inflammation and insulin resistance mainly by reducing inflammatory adipokine secretion, improving adiponectin secretion, reducing NF-κB/JNK activation, and inhibiting serine phosphorylation of IRS-1 receptors of insulin signalling pathway.