Nonalcoholic fatty liver disease(NAFLD) is today considered the most common form of chronic liver disease, affecting a high proportion of the population worldwide. NAFLD encompasses a large spectrum of liver damage, r...Nonalcoholic fatty liver disease(NAFLD) is today considered the most common form of chronic liver disease, affecting a high proportion of the population worldwide. NAFLD encompasses a large spectrum of liver damage, ranging from simple steatosis to steatohepatitis, advanced fibrosis and cirrhosis. Obesity, hyperglycemia, type 2 diabetes and hypertriglyceridemia are the most important risk factors. The pathogenesis of NAFLD and its progression to fibrosis and chronic liver disease is still unknown. Accumulating evidence indicates that mitochondrial dysfunction plays a key role in the physiopathology of NAFLD, although the mechanisms underlying this dysfunction are still unclear. Oxidative stress is considered an important factor in producing lethal hepatocyte injury associated with NAFLD. Mitochondrial respiratory chain is the main subcellular source of reactive oxygen species(ROS), which may damage mitochondrial proteins, lipids and mitochondrial DNA. Cardiolipin, a phospholipid located at the level of the inner mitochondrial membrane, plays an important role in several reactions and processes involved in mitochondrial bioenergetics as well as in mitochondrial dependent steps of apoptosis. This phospholipid is particularly susceptible to ROS attack. Cardiolipin peroxidation has been associated with mitochondrial dysfunction in multiple tissues in several physiopathological conditions, including NAFLD. In this review, we focus on the potential roles played by oxidative stress and cardiolipin alterations in mitochondrial dysfunction associated with NAFLD.展开更多
Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown etiology.It predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruct...Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown etiology.It predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruction of small-and medium-size intrahepatic bile ducts,portal inflammation and progressive scarring,which without proper treatment can ultimately lead to fibrosis and hepatic failure.Serum autoantibodies are crucial tools for differential diagnosis of PBC.While it is currently accepted that antimitochondrial antibodies are the most important serological markers of PBC,during the last five decades more than sixty autoantibodies have been explored in these patients,some of which had previously been thought to be specific for other autoimmune diseases.展开更多
Oxidative stress and mitochondrial damage have been implicated in the pathogenesis of several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. Oxidati...Oxidative stress and mitochondrial damage have been implicated in the pathogenesis of several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. Oxidative stress is characterized by the overproduction of reactive oxygen species, which can induce mitochondrial DNA mutations, damage the mitochondrial respiratory chain, alter membrane permeability, and influence Ca2+ homeostasis and mitochondrial defense systems. All these changes are implicated in the development of these neurodegenerative diseases, mediating or amplifying neuronal dysfunction and triggering neurodegeneration. This paper summarizes the contribution of oxidative stress and mitochondrial damage to the onset of neurodegenerative diseases and discusses strategies to modify mitochondrial dysfunction that may be attractive therapeutic interventions for the treatment of various neurodegenerative diseases.展开更多
Objective: To investigate the neuro-protective effects of Acanthopanax senticosus Harms(EAS) on mesencephalic mitochondria and the mechanism of action, using a mouse model of Parkinson's disease(PD). Methods: T...Objective: To investigate the neuro-protective effects of Acanthopanax senticosus Harms(EAS) on mesencephalic mitochondria and the mechanism of action, using a mouse model of Parkinson's disease(PD). Methods: The chemical fingerprint analysis of the extract of Acanthopanax senticosus Harms(EAS) was performed using the ultra performance liquid chromatograph and time of flight mass spectrometry. Thirty mice were randomly divided into the control group, the MPTP model group, and the EAS treated group with MPTP(MPTP+EAS group, 10 in each group). The MPTP model group and the MPTP+EAS group received MPTP-HCl(30 mg/kg i.p) once a day for 5 days. The control group received an equal volume of saline(20 m L/kg i.p) once a day for 5 days. Induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine hydrochloride daily(MPTP-HCl, 30 mg/kg) for 5 days, the PD mice were treated with EAS at 45.5 mg/kg daily for 20 days. The behavioral testing of mice was carried out using the pole-climbing test. The integrity and functions of neurons were examined in mesencephalic mitochondria in a PD mouse model, including nicotinamide adenine dinucleotide dehydrogenase ubiquinone flavoprotein 2(NDUFV2), mitochondrially encoded nicotinamide adenine dinucleotide dehydrogenase 1(MT-ND1), succinate dehydrogenase complex subunit A(SDHA), and succinate dehydrogenase cytochrome b560 subunit(SDHC). Results: After treatment with EAS, the behavioral changes induced by MPTP were attenuated significantly(P〈0.05). EAS protected the mesencephalic mitochondria from swelling and attenuated the decreases in their membrane potential(both P〈0.05), which was supported by an ultra-structural level analysis. The changes in reactive oxygen species(ROS), malonic dialdehyde(MDA), oxidative phosphorylation(OXPHOS) system 4 subunits levels and PD-related proteins expressions(parkin, Pink1, DJ-1, α-synuclein, and Lrrk2) reverted to near normal levels(all P〈0.05), based on the results展开更多
Alzheimer’s disease (AD) is an increasingly pressing worldwide public-health, social, political and economic concern. Despite significant investment in multiple traditional therapeutic strategies that have achieved...Alzheimer’s disease (AD) is an increasingly pressing worldwide public-health, social, political and economic concern. Despite significant investment in multiple traditional therapeutic strategies that have achieved success in preclinical models addressing the pathological hallmarks of the disease, these efforts have not translated into any effective disease-modifying therapies. This could be because interventions are being tested too late in the disease process. While existing therapies provide symptomatic and clinical benefit, they do not fully address the molecular abnormalities that occur in AD neurons. The pathophysiology of AD is complex; mitochondrial bioenergetic deficits and brain hypometabolism coupled with increased mitochondrial oxidative stress are antecedent and potentially play a causal role in the disease pathogenesis. Dysfunctional mitochondria accumulate from the combination of impaired mitophagy, which can also induce injurious inflammatory responses, and inadequate neuronal mitochondrial biogenesis. Altering the metabolic capacity of the brain by modulating/potentiating its mitochondrial bioenergetics may be a strategy for disease prevention and treatment. We present insights into the mechanisms of mitochondrial dysfunction in AD brain as well as an overview of emerging treatments with the potential to prevent, delay or reverse the neurodegenerative process by targeting mitochondria.展开更多
Glutamate is the most commonly engaged neurotransmitter in the mammalian central nervous system,acting to mediate excitatory neurotransmission.However,high levels of glutamatergic input elicit excitotoxicity,contribut...Glutamate is the most commonly engaged neurotransmitter in the mammalian central nervous system,acting to mediate excitatory neurotransmission.However,high levels of glutamatergic input elicit excitotoxicity,contribut-ing to neuronal cell death following acute brain injuries such as stroke and trauma.While excitotoxic cell death has also been implicated in some neurodegenerative disease models,the role of acute apoptotic cell death remains controversial in the setting of chronic neurodegeneration.Nevertheless,it is clear that excitatory synaptic dysregula-tion contributes to neurodegeneration,as evidenced by protective effects of partial N-methyl-D-aspartate receptor antagonists.Here,we review evidence for sublethal excitatory injuries in relation to neurodegeneration associated with Parkinson’s disease,Alzheimer’s disease,amyotrophic lateral sclerosis and Huntington’s disease.In contrast to classic excitotoxicity,emerging evidence implicates dysregulation of mitochondrial calcium handling in excitatory post-synaptic neurodegeneration.We discuss mechanisms that regulate mitochondrial calcium uptake and release,the impact of LRRK2,PINK1,Parkin,beta-amyloid and glucocerebrosidase on mitochondrial calcium transporters,and the role of autophagic mitochondrial loss in axodendritic shrinkage.Finally,we discuss strategies for normalizing the flux of calcium into and out of the mitochondrial matrix,thereby preventing mitochondrial calcium toxicity and excitotoxic dendritic loss.While the mechanisms that underlie increased uptake or decreased release of mitochondrial calcium vary in different model systems,a common set of strategies to normalize mitochondrial calcium flux can prevent excitatory mitochondrial toxicity and may be neuroprotective in multiple disease contexts.展开更多
AIM: To investigate in vitro the therapeutic effect and mechanisms of silybin in a cellular model of hepatic steatosis.METHODS: Rat hepatoma FaO cells were loaded with lipids by exposure to 0.75 mmol/L oleate/palmitat...AIM: To investigate in vitro the therapeutic effect and mechanisms of silybin in a cellular model of hepatic steatosis.METHODS: Rat hepatoma FaO cells were loaded with lipids by exposure to 0.75 mmol/L oleate/palmitate for 3 h to mimic liver steatosis. Then, the steatotic cells were incubated for 24 h with different concentrations (25 to 100 μmol/L) of silybin as phytosome complex with vitamin E. The effects of silybin on lipid accumulation and metabolism, and on indices of oxidative stress were evaluated by absorption and fluorescence microscopy, quantitative real-time PCR, Western blot, spectrophotometric and fluorimetric assays.RESULTS: Lipid-loading resulted in intracellular triglyceride (TG) accumulation inside lipid droplets, whose number and size increased. TG accumulation was mediated by increased levels of peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding protein-1c (SREBP-1c). The lipid imbalance was associated with higher production of reactive oxygen species (ROS) resulting in increased lipid peroxidation, stimulation of catalase activity and activation of nuclear factor kappa-B (NF-κB). Incubation of steatotic cells with silybin 50 μmol/L significantly reduced TG accumulation likely by promoting lipid catabolism and by inhibiting lipogenic pathways, as suggested by the changes in carnitine palmitoyltransferase 1 (CPT-1), PPAR and SREBP-1c levels. The reduction in fat accumulation exerted by silybin in the steatotic cells was associated with the improvement of the oxidative imbalance caused by lipid excess as demonstrated by the reduction in ROS content, lipid peroxidation, catalase activity and NF-κB activation.CONCLUSION: We demonstrated the direct anti-steatotic and anti-oxidant effects of silybin in steatotic cells, thus elucidating at a cellular level the encouraging results demonstrated in clinical and animal studies.展开更多
Hydrogen sulfide is an antioxidant molecule that has a wide range of biological effects against oxidative stress. Balanced oxidative stress is also vital for maintaining cellular function in biological system, where r...Hydrogen sulfide is an antioxidant molecule that has a wide range of biological effects against oxidative stress. Balanced oxidative stress is also vital for maintaining cellular function in biological system, where reactive oxygen species are the main source of oxidative stress. When the normal redox balance is disturbed, deoxyribonucleic acid, lipid, and protein molecules are oxidized under pathological conditions, like diabetes mellitus that leads to diabetic peripheral neuropathy. In diabetes mellitus-induced diabetic peripheral neuropathy, due to hyperglycemia, pancreatic beta cell(β cell) shows resistance to insulin secretion. As a consequence, glucose metabolism is disturbed in neuronal cells which are distracted from providing proper cell signaling pathway. Not only diabetic peripheral neuropathy but also other central damages occur in brain neuropathy. Neurological studies regarding type 1 diabetes mellitus patients with Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis have shown changes in the central nervous system because high blood glucose levels(HbA1 c) appeared with poor cognitive function. Oxidative stress plays a role in inhibiting insulin signaling that is necessary for brain function. Hydrogen sulfide exhibits antioxidant effects against oxidative stress, where cystathionine β synthase, cystathionine γ lyase, and 3-mercaptopyruvate sulfurtransferase are the endogenous sources of hydrogen sulfide. This review is to explore the pathogenesis of diabetes mellitus-induced diabetic peripheral neuropathy and other neurological comorbid disorders under the oxidative stress condition and the anti-oxidative effects of hydrogen sulfide.展开更多
The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial d...The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial dysfunction and aberrant accumulation of misfolded proteins or peptides in specific areas of the brain. The most prevalent neurodegenerative diseases belonging to age-related pathologies are Alzheimer's disease, Huntington's disease, Parkinson's disease and amyotrophic lateral sclerosis. Interestingly, mitochondrial dysfunction has been observed to occur during the early onset of several neuropathological events associated to neurodegenerative diseases. The master regulator of mitochondrial quality control and energetic metabolism is the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC-1α). Additionally, it has been observed that PGC-1α appears to be a key factor in maintaining neuronal survival and synaptic transmission. In fact, PGC-1α downregulation in different brain areas(hippocampus, substantia nigra, cortex, striatum and spinal cord) that occurs in function of neurological damage including oxidative stress, neuronal loss, and motor disorders has been seen in several animal and cellular models of neurodegenerative diseases. Current evidence indicates that PGC-1α upregulation may serve as a potent therapeutic approach against development and progression of neuronal damage. Remarkably, increasing evidence shows that PGC-1α deficient mice have neurodegenerative diseases-like features, as well as neurological abnormalities. Finally, we discuss recent studies showing novel specific PGC-1α isoforms in the central nervous system that appear to exert a key role in the age of onset of neurodegenerative diseases and have a neuroprotective function in the central nervous system, thus opening a new molecular strategy for treatment of neurodegenerative diseases. The purpose of this review is to provide an up-to-date overview of the PGC-1α role in the展开更多
AIM To investigate the role of the miR-133a-UCP2 pathway in the pathogenesis of inflammatory bowel disease (IBD) and to explore the potential downstream mechanisms with respect to inflammation, oxidative stress and en...AIM To investigate the role of the miR-133a-UCP2 pathway in the pathogenesis of inflammatory bowel disease (IBD) and to explore the potential downstream mechanisms with respect to inflammation, oxidative stress and energy metabolism. METHODS C57BL/6 mice were fed dextran sulfate sodium (DSS) liquid for 7 consecutive days, followed by the administration of saline to the DSS group, UCP2 siRNA to the UCP2 group and a miR-133a mimic to the miR-133a group on days 8 and 11. Body weight, stool consistency and rectal bleeding were recorded daily, and these composed the disease activity index (DAI) score for the assessment of disease severity. After cervical dislocation was performed on day 14, the length of the colon in each mouse was measured, and colonic tissue was collected for further study, which included the following: haematoxylin and eosin staining, UCP2 and miR-133a detection by immunohistochemical staining, western blot and quantitative real-time PCR, measurement of apoptosis by TUNEL assay, and the assessment of inflammation (TNF-alpha, IL-1 beta, IL-6 and MCP1), oxidative stress (H2O2 and MDA) and metabolic parameters (ATP) by ELISA and colorimetric methods. RESULTS An animal model of IBD was successfully established, as shown by an increased DAI score, shortened colon length and specific pathologic changes, along with significantly increased UCP2 and decreased miR-133a levels. Compared with the DSS group, the severity of IBD was alleviated in the UCP2 and the miR-133a groups after successful UCP2 knockdown and miR-133a overexpression. The extent of apoptosis, as well as the levels of TNF-alpha, IL-1 beta, MDA and ATP, were significantly increased in both the UCP2 and miR-133a groups compared with the DSS group. CONCLUSION The miR-133a-UCP2 pathway participates in IBD by altering downstream inflammation, oxidative stress and markers of energy metabolism, which provides novel clues and potential therapeutic targets for IBD.展开更多
Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age.However,no satisfactory the...Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age.However,no satisfactory therapeutic strategies have been available for mitochondrial diseases so far.Mitochondrial transplantation is a burgeoning approach for treatment of mitochondrial diseases by recovery of dysfunctional mitochondria in defective cells using isolated functional mitochondria.Many models of mitochondrial transplantation in cells,animals,and patients have proved effective via various routes of mitochondrial delivery.This review presents different techniques used in mitochondrial isolation and delivery,mechanisms of mitochondrial internalization and consequences of mitochondrial transplantation,along with challenges for clinical application.Despite some unknowns and challenges,mitochondrial transplantation would provide an innovative approach for mitochondrial medicine.展开更多
The Stem Cell Ophthalmology Treatment Study (SCOTS) is currently the largest-scale stem cell ophthal- mology trial registered at ClinicalTrials.gov (identifier: NCT01920867). SCOTS utilizes autologous bone marrow...The Stem Cell Ophthalmology Treatment Study (SCOTS) is currently the largest-scale stem cell ophthal- mology trial registered at ClinicalTrials.gov (identifier: NCT01920867). SCOTS utilizes autologous bone marrow-derived stem cells (BMSCs) to treat optic nerve and retinal diseases. Treatment approaches include a combination of retrobulbar, subtenon, intravitreal, intra-optic nerve, subretinal, and intravenous injection of autologous BMSCs according to the nature of the disease, the degree of visual loss, and any risk factors related to the treatments. Patients with Leber's hereditary optic neuropathy had visual acuity gains on the Early Treatment Diabetic Retinopathy Study (ETDRS) of up to 35 letters and Snellen acuity improvements from hand motion to 20/200 and from counting fingers to 20/100. Visual field improvements were noted. Macular and optic nerve head nerve fiber layer typically thickened. No serious complications were seen. The increases in visual acuity obtained in our study were encouraging and suggest that the use of autolo- gous BMSCs as provided in SCOTS for ophthalmologic mitochondrial diseases including Leber's hereditary optic neuropathy may be a viable treatment option.展开更多
文摘Nonalcoholic fatty liver disease(NAFLD) is today considered the most common form of chronic liver disease, affecting a high proportion of the population worldwide. NAFLD encompasses a large spectrum of liver damage, ranging from simple steatosis to steatohepatitis, advanced fibrosis and cirrhosis. Obesity, hyperglycemia, type 2 diabetes and hypertriglyceridemia are the most important risk factors. The pathogenesis of NAFLD and its progression to fibrosis and chronic liver disease is still unknown. Accumulating evidence indicates that mitochondrial dysfunction plays a key role in the physiopathology of NAFLD, although the mechanisms underlying this dysfunction are still unclear. Oxidative stress is considered an important factor in producing lethal hepatocyte injury associated with NAFLD. Mitochondrial respiratory chain is the main subcellular source of reactive oxygen species(ROS), which may damage mitochondrial proteins, lipids and mitochondrial DNA. Cardiolipin, a phospholipid located at the level of the inner mitochondrial membrane, plays an important role in several reactions and processes involved in mitochondrial bioenergetics as well as in mitochondrial dependent steps of apoptosis. This phospholipid is particularly susceptible to ROS attack. Cardiolipin peroxidation has been associated with mitochondrial dysfunction in multiple tissues in several physiopathological conditions, including NAFLD. In this review, we focus on the potential roles played by oxidative stress and cardiolipin alterations in mitochondrial dysfunction associated with NAFLD.
文摘Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown etiology.It predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruction of small-and medium-size intrahepatic bile ducts,portal inflammation and progressive scarring,which without proper treatment can ultimately lead to fibrosis and hepatic failure.Serum autoantibodies are crucial tools for differential diagnosis of PBC.While it is currently accepted that antimitochondrial antibodies are the most important serological markers of PBC,during the last five decades more than sixty autoantibodies have been explored in these patients,some of which had previously been thought to be specific for other autoimmune diseases.
基金supported by the National Natural Science Foundation of China,No.81274005Medical Science Research,Health Department of Hebei Province,No.20110173,20090588Hebei Education Department Science Foundation,No.2007302
文摘Oxidative stress and mitochondrial damage have been implicated in the pathogenesis of several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. Oxidative stress is characterized by the overproduction of reactive oxygen species, which can induce mitochondrial DNA mutations, damage the mitochondrial respiratory chain, alter membrane permeability, and influence Ca2+ homeostasis and mitochondrial defense systems. All these changes are implicated in the development of these neurodegenerative diseases, mediating or amplifying neuronal dysfunction and triggering neurodegeneration. This paper summarizes the contribution of oxidative stress and mitochondrial damage to the onset of neurodegenerative diseases and discusses strategies to modify mitochondrial dysfunction that may be attractive therapeutic interventions for the treatment of various neurodegenerative diseases.
基金Supported by the National Natural Science Foundation of China(No.81270056)China Postdoctoral Science Foundation(No.2013T60398)+2 种基金Scientific Research grants of Postdoctoral Researchers Settled in Heilongjiang(No.LBH-Q13160)Outstanding Talents Cultivation Fund of Heilongjiang University of Chinese Medicine(No.2013jc01)the Outstanding Innovative Talent Support Programs of Heilongjiang University of Chinese Medicine
文摘Objective: To investigate the neuro-protective effects of Acanthopanax senticosus Harms(EAS) on mesencephalic mitochondria and the mechanism of action, using a mouse model of Parkinson's disease(PD). Methods: The chemical fingerprint analysis of the extract of Acanthopanax senticosus Harms(EAS) was performed using the ultra performance liquid chromatograph and time of flight mass spectrometry. Thirty mice were randomly divided into the control group, the MPTP model group, and the EAS treated group with MPTP(MPTP+EAS group, 10 in each group). The MPTP model group and the MPTP+EAS group received MPTP-HCl(30 mg/kg i.p) once a day for 5 days. The control group received an equal volume of saline(20 m L/kg i.p) once a day for 5 days. Induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine hydrochloride daily(MPTP-HCl, 30 mg/kg) for 5 days, the PD mice were treated with EAS at 45.5 mg/kg daily for 20 days. The behavioral testing of mice was carried out using the pole-climbing test. The integrity and functions of neurons were examined in mesencephalic mitochondria in a PD mouse model, including nicotinamide adenine dinucleotide dehydrogenase ubiquinone flavoprotein 2(NDUFV2), mitochondrially encoded nicotinamide adenine dinucleotide dehydrogenase 1(MT-ND1), succinate dehydrogenase complex subunit A(SDHA), and succinate dehydrogenase cytochrome b560 subunit(SDHC). Results: After treatment with EAS, the behavioral changes induced by MPTP were attenuated significantly(P〈0.05). EAS protected the mesencephalic mitochondria from swelling and attenuated the decreases in their membrane potential(both P〈0.05), which was supported by an ultra-structural level analysis. The changes in reactive oxygen species(ROS), malonic dialdehyde(MDA), oxidative phosphorylation(OXPHOS) system 4 subunits levels and PD-related proteins expressions(parkin, Pink1, DJ-1, α-synuclein, and Lrrk2) reverted to near normal levels(all P〈0.05), based on the results
文摘Alzheimer’s disease (AD) is an increasingly pressing worldwide public-health, social, political and economic concern. Despite significant investment in multiple traditional therapeutic strategies that have achieved success in preclinical models addressing the pathological hallmarks of the disease, these efforts have not translated into any effective disease-modifying therapies. This could be because interventions are being tested too late in the disease process. While existing therapies provide symptomatic and clinical benefit, they do not fully address the molecular abnormalities that occur in AD neurons. The pathophysiology of AD is complex; mitochondrial bioenergetic deficits and brain hypometabolism coupled with increased mitochondrial oxidative stress are antecedent and potentially play a causal role in the disease pathogenesis. Dysfunctional mitochondria accumulate from the combination of impaired mitophagy, which can also induce injurious inflammatory responses, and inadequate neuronal mitochondrial biogenesis. Altering the metabolic capacity of the brain by modulating/potentiating its mitochondrial bioenergetics may be a strategy for disease prevention and treatment. We present insights into the mechanisms of mitochondrial dysfunction in AD brain as well as an overview of emerging treatments with the potential to prevent, delay or reverse the neurodegenerative process by targeting mitochondria.
文摘Glutamate is the most commonly engaged neurotransmitter in the mammalian central nervous system,acting to mediate excitatory neurotransmission.However,high levels of glutamatergic input elicit excitotoxicity,contribut-ing to neuronal cell death following acute brain injuries such as stroke and trauma.While excitotoxic cell death has also been implicated in some neurodegenerative disease models,the role of acute apoptotic cell death remains controversial in the setting of chronic neurodegeneration.Nevertheless,it is clear that excitatory synaptic dysregula-tion contributes to neurodegeneration,as evidenced by protective effects of partial N-methyl-D-aspartate receptor antagonists.Here,we review evidence for sublethal excitatory injuries in relation to neurodegeneration associated with Parkinson’s disease,Alzheimer’s disease,amyotrophic lateral sclerosis and Huntington’s disease.In contrast to classic excitotoxicity,emerging evidence implicates dysregulation of mitochondrial calcium handling in excitatory post-synaptic neurodegeneration.We discuss mechanisms that regulate mitochondrial calcium uptake and release,the impact of LRRK2,PINK1,Parkin,beta-amyloid and glucocerebrosidase on mitochondrial calcium transporters,and the role of autophagic mitochondrial loss in axodendritic shrinkage.Finally,we discuss strategies for normalizing the flux of calcium into and out of the mitochondrial matrix,thereby preventing mitochondrial calcium toxicity and excitotoxic dendritic loss.While the mechanisms that underlie increased uptake or decreased release of mitochondrial calcium vary in different model systems,a common set of strategies to normalize mitochondrial calcium flux can prevent excitatory mitochondrial toxicity and may be neuroprotective in multiple disease contexts.
基金Supported by MIUR-COFIN(Prot.20089SRS2X_002)Compagnia San Paolo Torino+1 种基金University of Genovaand Fondazione CARIGE
文摘AIM: To investigate in vitro the therapeutic effect and mechanisms of silybin in a cellular model of hepatic steatosis.METHODS: Rat hepatoma FaO cells were loaded with lipids by exposure to 0.75 mmol/L oleate/palmitate for 3 h to mimic liver steatosis. Then, the steatotic cells were incubated for 24 h with different concentrations (25 to 100 μmol/L) of silybin as phytosome complex with vitamin E. The effects of silybin on lipid accumulation and metabolism, and on indices of oxidative stress were evaluated by absorption and fluorescence microscopy, quantitative real-time PCR, Western blot, spectrophotometric and fluorimetric assays.RESULTS: Lipid-loading resulted in intracellular triglyceride (TG) accumulation inside lipid droplets, whose number and size increased. TG accumulation was mediated by increased levels of peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding protein-1c (SREBP-1c). The lipid imbalance was associated with higher production of reactive oxygen species (ROS) resulting in increased lipid peroxidation, stimulation of catalase activity and activation of nuclear factor kappa-B (NF-κB). Incubation of steatotic cells with silybin 50 μmol/L significantly reduced TG accumulation likely by promoting lipid catabolism and by inhibiting lipogenic pathways, as suggested by the changes in carnitine palmitoyltransferase 1 (CPT-1), PPAR and SREBP-1c levels. The reduction in fat accumulation exerted by silybin in the steatotic cells was associated with the improvement of the oxidative imbalance caused by lipid excess as demonstrated by the reduction in ROS content, lipid peroxidation, catalase activity and NF-κB activation.CONCLUSION: We demonstrated the direct anti-steatotic and anti-oxidant effects of silybin in steatotic cells, thus elucidating at a cellular level the encouraging results demonstrated in clinical and animal studies.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning,No.2018R1A2B6001123(to NYJ),No.2018R1D1A1B07040282(to JJ)
文摘Hydrogen sulfide is an antioxidant molecule that has a wide range of biological effects against oxidative stress. Balanced oxidative stress is also vital for maintaining cellular function in biological system, where reactive oxygen species are the main source of oxidative stress. When the normal redox balance is disturbed, deoxyribonucleic acid, lipid, and protein molecules are oxidized under pathological conditions, like diabetes mellitus that leads to diabetic peripheral neuropathy. In diabetes mellitus-induced diabetic peripheral neuropathy, due to hyperglycemia, pancreatic beta cell(β cell) shows resistance to insulin secretion. As a consequence, glucose metabolism is disturbed in neuronal cells which are distracted from providing proper cell signaling pathway. Not only diabetic peripheral neuropathy but also other central damages occur in brain neuropathy. Neurological studies regarding type 1 diabetes mellitus patients with Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis have shown changes in the central nervous system because high blood glucose levels(HbA1 c) appeared with poor cognitive function. Oxidative stress plays a role in inhibiting insulin signaling that is necessary for brain function. Hydrogen sulfide exhibits antioxidant effects against oxidative stress, where cystathionine β synthase, cystathionine γ lyase, and 3-mercaptopyruvate sulfurtransferase are the endogenous sources of hydrogen sulfide. This review is to explore the pathogenesis of diabetes mellitus-induced diabetic peripheral neuropathy and other neurological comorbid disorders under the oxidative stress condition and the anti-oxidative effects of hydrogen sulfide.
基金supported by Fondecyt 1200908(to JF)the Conicyt 21141247(to JDP)。
文摘The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial dysfunction and aberrant accumulation of misfolded proteins or peptides in specific areas of the brain. The most prevalent neurodegenerative diseases belonging to age-related pathologies are Alzheimer's disease, Huntington's disease, Parkinson's disease and amyotrophic lateral sclerosis. Interestingly, mitochondrial dysfunction has been observed to occur during the early onset of several neuropathological events associated to neurodegenerative diseases. The master regulator of mitochondrial quality control and energetic metabolism is the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC-1α). Additionally, it has been observed that PGC-1α appears to be a key factor in maintaining neuronal survival and synaptic transmission. In fact, PGC-1α downregulation in different brain areas(hippocampus, substantia nigra, cortex, striatum and spinal cord) that occurs in function of neurological damage including oxidative stress, neuronal loss, and motor disorders has been seen in several animal and cellular models of neurodegenerative diseases. Current evidence indicates that PGC-1α upregulation may serve as a potent therapeutic approach against development and progression of neuronal damage. Remarkably, increasing evidence shows that PGC-1α deficient mice have neurodegenerative diseases-like features, as well as neurological abnormalities. Finally, we discuss recent studies showing novel specific PGC-1α isoforms in the central nervous system that appear to exert a key role in the age of onset of neurodegenerative diseases and have a neuroprotective function in the central nervous system, thus opening a new molecular strategy for treatment of neurodegenerative diseases. The purpose of this review is to provide an up-to-date overview of the PGC-1α role in the
基金National Natural Science Foundation of China,No.81370008 and No.81000169Natural Science Foundation of Zhejiang Province,No.R2110159,No.LY15H030006 and No.LY16H030003
文摘AIM To investigate the role of the miR-133a-UCP2 pathway in the pathogenesis of inflammatory bowel disease (IBD) and to explore the potential downstream mechanisms with respect to inflammation, oxidative stress and energy metabolism. METHODS C57BL/6 mice were fed dextran sulfate sodium (DSS) liquid for 7 consecutive days, followed by the administration of saline to the DSS group, UCP2 siRNA to the UCP2 group and a miR-133a mimic to the miR-133a group on days 8 and 11. Body weight, stool consistency and rectal bleeding were recorded daily, and these composed the disease activity index (DAI) score for the assessment of disease severity. After cervical dislocation was performed on day 14, the length of the colon in each mouse was measured, and colonic tissue was collected for further study, which included the following: haematoxylin and eosin staining, UCP2 and miR-133a detection by immunohistochemical staining, western blot and quantitative real-time PCR, measurement of apoptosis by TUNEL assay, and the assessment of inflammation (TNF-alpha, IL-1 beta, IL-6 and MCP1), oxidative stress (H2O2 and MDA) and metabolic parameters (ATP) by ELISA and colorimetric methods. RESULTS An animal model of IBD was successfully established, as shown by an increased DAI score, shortened colon length and specific pathologic changes, along with significantly increased UCP2 and decreased miR-133a levels. Compared with the DSS group, the severity of IBD was alleviated in the UCP2 and the miR-133a groups after successful UCP2 knockdown and miR-133a overexpression. The extent of apoptosis, as well as the levels of TNF-alpha, IL-1 beta, MDA and ATP, were significantly increased in both the UCP2 and miR-133a groups compared with the DSS group. CONCLUSION The miR-133a-UCP2 pathway participates in IBD by altering downstream inflammation, oxidative stress and markers of energy metabolism, which provides novel clues and potential therapeutic targets for IBD.
基金supported by grants from the National Natural Science Foundation of China Young Program(No.81903728)the National Natural Science Foundation of China Major Project(No.81730098).
文摘Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age.However,no satisfactory therapeutic strategies have been available for mitochondrial diseases so far.Mitochondrial transplantation is a burgeoning approach for treatment of mitochondrial diseases by recovery of dysfunctional mitochondria in defective cells using isolated functional mitochondria.Many models of mitochondrial transplantation in cells,animals,and patients have proved effective via various routes of mitochondrial delivery.This review presents different techniques used in mitochondrial isolation and delivery,mechanisms of mitochondrial internalization and consequences of mitochondrial transplantation,along with challenges for clinical application.Despite some unknowns and challenges,mitochondrial transplantation would provide an innovative approach for mitochondrial medicine.
文摘The Stem Cell Ophthalmology Treatment Study (SCOTS) is currently the largest-scale stem cell ophthal- mology trial registered at ClinicalTrials.gov (identifier: NCT01920867). SCOTS utilizes autologous bone marrow-derived stem cells (BMSCs) to treat optic nerve and retinal diseases. Treatment approaches include a combination of retrobulbar, subtenon, intravitreal, intra-optic nerve, subretinal, and intravenous injection of autologous BMSCs according to the nature of the disease, the degree of visual loss, and any risk factors related to the treatments. Patients with Leber's hereditary optic neuropathy had visual acuity gains on the Early Treatment Diabetic Retinopathy Study (ETDRS) of up to 35 letters and Snellen acuity improvements from hand motion to 20/200 and from counting fingers to 20/100. Visual field improvements were noted. Macular and optic nerve head nerve fiber layer typically thickened. No serious complications were seen. The increases in visual acuity obtained in our study were encouraging and suggest that the use of autolo- gous BMSCs as provided in SCOTS for ophthalmologic mitochondrial diseases including Leber's hereditary optic neuropathy may be a viable treatment option.