Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage

The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial dysfunction.Dysfunctional mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging cells.In response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological conditions.Specific interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid hemorrhage.This review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control mechanisms.It also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage.

Latest assessment methods for mitochondrial homeostasis in cognitive diseases

Mitochondria play an essential role in neural function,such as supporting normal energy metabolism,regulating reactive oxygen species,buffering physiological calcium loads,and maintaining the balance of morphology,subcellular distribution,and overall health through mitochondrial dynamics.Given the recent technological advances in the assessment of mitochondrial structure and functions,mitochondrial dysfunction has been regarded as the early and key pathophysiological mechanism of cognitive disorders such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,mild cognitive impairment,and postoperative cognitive dysfunction.This review will focus on the recent advances in mitochondrial medicine and research methodology in the field of cognitive sciences,from the perspectives of energy metabolism,oxidative stress,calcium homeostasis,and mitochondrial dynamics(including fission-fusion,transport,and mitophagy).

Low Selenium and Low Protein Exacerbate Myocardial Damage in Keshan Disease by Affecting the PINK1/Parkin-mediated Mitochondrial Autophagy Pathway

Objective Keshan disease(KD)is a myocardial mitochondrial disease closely related to insufficient selenium(Se)and protein intake.PTEN induced putative kinase 1(PINK1)/Parkin mediated mitochondrial autophagy regulates various physiological and pathological processes in the body.This study aimed to elucidate the relationship between PINK1/Parkin-regulated mitochondrial autophagy and KD-related myocardial injury.Methods A low Se and low protein animal model was established.One hundred Wistar rats were randomly divided into 5 groups(control group,low Se group,low protein group,low Se+low protein group,and corn from KD area group).The JC-1 method was used to detect the mitochondrial membrane potential(MMP).ELISA was used to detect serum creatine kinase MB(CK-MB),cardiac troponin I(cTnI),and mitochondrial-glutamicoxalacetic transaminase(M-GOT)levels.RT-PCR and Western blot analysis were used to detect the expression of PINK1,Parkin,sequestome 1(P62),and microtubule-associated proteins1A/1B light chain 3B(MAP1LC3B).Results The MMP was significantly decreased and the activity of CK-MB,cTnI,and M-GOT significantly increased in each experimental group(low Se group,low protein group,low Se+low protein group and corn from KD area group)compared with the control group(P<0.05 for all).The mRNA and protein expression levels of PINK1,Parkin and MAP1LC3B were profoundly increased,and those of P62 markedly decreased in the experimental groups compared with the control group(P<0.05 for all).Conclusion Low Se and low protein levels exacerbate myocardial damage in KD by affecting the PINK1/Parkin-mediated mitochondrial autophagy pathway.

Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells

BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells.

Generation of mitochondrial replacement monkeys by female pronucleus transfer

Mutations in mitochondrial DNA(mtDNA)are maternally inherited and have the potential to cause severe disorders.Mitochondrial replacement therapies,including spindle,polar body,and pronuclear transfers,are promising strategies for preventing the hereditary transmission of mtDNA diseases.While pronuclear transfer has been used to generate mitochondrial replacement mouse models and human embryos,its application in non-human primates has not been previously reported.In this study,we successfully generated four healthy cynomolgus monkeys(Macaca fascicularis)via female pronuclear transfer.These individuals all survived for more than two years and exhibited minimal mtDNA carryover(3.8%–6.7%),as well as relatively stable mtDNA heteroplasmy dynamics during development.The successful establishment of this nonhuman primate model highlights the considerable potential of pronuclear transfer in reducing the risk of inherited mtDNA diseases and provides a valuable preclinical research model for advancing mitochondrial replacement therapies in humans.

Resveratrol combats chronic diseases through enhancing mitochondrial quality

Resveratrol(RSV),as a functional food component extracted from natural plants,has been widely studied and recognized in preventing and treating various diseases,with major mechanisms including executing anti-inflammation and anti-oxidation functions,and improving mitochondrial quality.Chronic diseases as non-communicable diseases are mainly caused by multiple factors,such as physiological decline and dysfunction in the body,and have become a significant challenge on public health worldwide.It is worth noting that chronic diseases such as Alzheimer's disease(AD),Parkinson's disease(PD),muscle atrophy,cardiovascular disease,obesity,and cancer are accompanied by abnormal mitochondrial function.Therefore,targeted regulation of mitochondria may be a meaningful way to prevent and treat chronic diseases.Increasing evidence has confirmed that RSV is actively involved in regulating mitochondria,and it has become an essential consideration to prevent and treat chronic diseases through targeting mitochondria and improving corresponding functions.In this article,current studies on RSV to optimize mitochondrial quality for preventing and alleviating chronic disease are systematically summarized,which can provide a theoretical reference for the development of functional foods or drugs to combat chronic diseases.

Characterization,expression dynamics,and potential function of OPA1 for regulation of mitochondrial morphology during spermiogenesis in Phascolosoma esculenta

Mitochondria undergo morphological changes during spermatogenesis in some animals.The mechanism and role of mitochondrial morphology regulation,however,remain somewhat unclear.In this study,we analyzed the molecular characteristics,expression dynamics and subcellular localization of optic atrophy protein 1(OPA1),a mitochondrial fusion and cristae maintenance-related protein,to reveal the possible regulatory mechanisms underlying mitochondrial morphology in Phascolosoma esculenta spermiogenesis.The full-length cDNA of the P.esculenta opa1 gene(Pe-opa1)is 3743 bp in length and encodes 975 amino acids.The Pe-OPA1 protein is highly conservative and includes a transmembrane domain,a GTPase domain,two helical bundle domains,and a lipid-interacting stalk.Gene and protein expression was higher in the coelomic fluid(a site of spermatid development)of male P.esculenta and increased first and then decreased from March to December.Moreover,their expression during the breeding stage was significantly higher than during the non-breeding stage,suggesting that Pe-OPA1 is involved in P.esculenta reproduction.The Pe-OPA1 protein was more abundant in components consisting of many spermatids than in components without,indicating that Pe-OPA1 mainly plays a role in the spermatid in coelomic fluid.Moreover,Pe-OPA1 was mainly detected in the spermatid mitochondria.Immunofluorescence experiments showed that the Pe-OPA1 are constitutively expressed and co-localized with mitochondria during spermiogenesis,suggesting its involvement in P.esculenta spermiogenesis.These results provide evidence for Pe-OPA1's involvement in the regulation of mitochondrial morphology during spermiogenesis.

Molecular phylogenetic relationships based on mitochondrial genomes of novel deep-sea corals(Octocorallia:Alcyonacea):Insights into slow evolution and adaptation to extreme deep-sea environments

A total of 10 specimens of Alcyonacea corals were collected at depths ranging from 905 m to 1633 m by the manned submersible Shenhai Yongshi during two cruises in the South China Sea(SCS).Based on mitochondrial genomic characteristics,morphological examination,and sclerite scanning electron microscopy,the samples were categorized into four suborders(Calcaxonia,Holaxonia,Scleraxonia,and Stolonifera),and identified as 9 possible new cold-water coral species.Assessments of GC-skew dissimilarity,phylogenetic distance,and average nucleotide identity(ANI)revealed a slow evolutionary rate for the octocoral mitochondrial sequences.The nonsynonymous(Ka)to synonymous(Ks)substitution ratio(Ka/Ks)suggested that the 14 protein-coding genes(PCGs)were under purifying selection,likely due to specific deep-sea environmental pressures.Correlation analysis of the median Ka/Ks values of five gene families and environmental factors indicated that the genes encoding cytochrome b(cyt b)and DNA mismatch repair protein(mutS)may be influenced by environmental factors in the context of deep-sea species formation.This study highlights the slow evolutionary pace and adaptive mechanisms of deep-sea corals.

Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease

Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis.

Mitochondrial therapeutics and mitochondrial transfer for neurodegenerative diseases and aging

Mitochondrial dysfunction and neurodegeneration:Progressive neurodegenerative diseases affect a significant proportion of the population;in a single year,there are as many as 276 million disabilities and 9 million deaths as a result of neurological diseases.

Gene characterization and phylogenetic analysis of four mitochondrial genomes in Caenogastropoda

Caenogastropoda is a highly diverse group,containing~60%of all existing gastropods.Species in this subclass predominantly inhabit marine environments and have a high ecological and economic value.Owing to the increase in relevant phylogenetic studies,our understanding of between species relatedness in Caenogastropoda has improved.However,the biodiversity,taxonomic status,and phylogenetic relationships of this group remain unclear.In the present study,we performed next-generation sequencing of four complete mitochondrial genomes from three families(Buccinidae,Columbellidae,and Cypraeidae)and the four mitogenomes were classical circular structures,with a length of 16177 bp in Volutharpa ampullacea,16244 bp in Mitrella albuginosa,16926bp in Mauritia arabica asiatica and 15422 bp in Erronea errones.Base composition analysis indicated that whole sequences were biased toward A and T.Then compared them with 171 complete mitochondrial genomes of Caenogastropoda.The phylogenetic relationship of Caenogastropoda derived from Maximum Likelihood(ML)and Bayesian Inference(BI)trees constructed based on CDS sequences was consistent with the results of traditional morphological analysis,with all three families showing close relationships.This study supported Caenogastropoda at the molecular level as a separate clade of Mollusca.According to our divergence time estimations,Caenogastropoda was formed during the middle Triassic period(~247.2–237 Ma).Our novel mitochondrial genomes provide evidence for the speciation of Caenogastropoda in addition to elucidating the mitochondrial genomic evolution of this subclass.

Prohibitin 1 inhibits cell proliferation and induces apoptosis via the p53-mediated mitochondrial pathway in vitro

BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and survival.Emerging evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is controversial.AIM To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in vitro.METHODS HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using ELISA,RT-PCR,and immunohistoche-mistry.Human HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 h.Cell prolif-eration was analysed with an MTT assay.Cell cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,respectively.RESULTS Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/L.Overexpression of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent manner.FACS revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced apoptosis.The proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compared with untreated control and empty vector-transfected cells.The percentage of apoptotic HepG2 cells that were transfected with pEGFP-PHB1 was 15.41%±1.06%,which was significantly greater than that of apoptotic control cells(3.65%±0.85%,P<0.01)and empty vector-transfected cells(4.21%±0.52%,P<0.01).Similar results were obtained with SMMC-7721 cells.Furthermore,the mRNA and protein expression levels of p53,p21,Bax,caspase 3,and caspase 9 were increased while the mRNA and protein expression levels of Cyclin A2,Cy-clin E1,CDK2,and Bcl-2 were decreased when PHB1 was overexpressed in human HCC cells.However,when PHB1 was upregulated in human HCC cells,Cyt C expression levels were increased in the cytosol and decreased in the mitochondria,which indicated that Cyt C had been released into the cytosol.Conversely,these effects were reversed when PHB1 was knocked down.CONCLUSION PHB1 inhibits human HCC cell viability by arresting the cell cycle and inducing cell apoptosis via activation of the p53-mediated mitochondrial pathway.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

Research progress in mitochondrial autophagy mediated by BNIP3

Mitochondrial autophagy is widely found in mammals,and plays an important role in maintaining mitochondrial balance and mitochondrial quality control in cells.In this review,we reviewed the research progress of BNIP3-mediated mitochondrial autophagy and diseases in recent 5 years,providing new ideas for clinical diagnosis and treatment.

YBX1 inhibits mitochondrial-mediated apoptosis in ischemic heart through the PI3K/AKT signaling pathway

Background:Myocardial infarction(MI)is associated with higher morbidity and mortality in the world,especially in cold weather.YBX1 is an RNA-binding protein that is required for pathological growth of cardiomyocyte by regulating cell growth and protein synthesis.But YBX1,as an individual RNA-binding protein,regulates cardiomyocytes through signaling cascades during myocardial infarction remain largely unexplored.Methods:In vivo,the mouse MI model was induced by ligating the left anterior descending coronary artery(LAD),and randomly divided into sham operation group,MI group,MI+YBX1 knockdown/overexpression group and MI+negative control(NC)group.The protective effect of YBX1 was verified by echocardiography and triphenyltetrazolium chloride staining.In vitro,mitochondrial-dependent apoptosis was investigated by using CCK8,TUNEL staining,reactive oxygen species(ROS)staining and JC-1 staining in hypoxic neonatal mouse cardiomyocytes(NMCMs).Results:YBX1 expression of cardiomyocytes was downregulated in a mouse model and a cellular model on the ischemic condition.Compared to mice induced by MI,YBX1 overexpression mediated by adeno-associated virus serotype 9(AAV9)vector reduced the infarcted size and improved cardiac function.Knockdown of endogenous YBX1 by shRNA partially aggravated ischemia-induced cardiac dysfunction.In hypoxic cardiomyocytes,YBX1 overexpression decreased lactic dehydrogenase(LDH)release,increased cell viability,and inhibited apoptosis by affecting the expression of apoptosis related proteins,while knockdown of endogenous YBX1 by siRNA had the opposite effect.Overexpression of YBX1 restored mitochondrial dysfunction in hypoxic NMCMs by increasing mitochondrial membrane potential and ATP content and decreasing ROS.In hypoxic NMCMs,YBX1 overexpression increased the expression of phosphorylated phosphatidylinositol 3 kinase(PI3K)/AKT,and the anti-apoptosis effect of YBX1 was eliminated t by LY294002,PI3K/AKT inhibitor.Conclusion:YBX1 protected the heart from ischemic damage by inhibiting the mitochondrial-dependent apoptosis through PI3K/AKT pathway.It is anticipated that YBX1 may serve as a novel therapeutic target for MI.

The Fang’s hypoglycemic formula improves insulin resistance in type 2 diabetes mellitus by regulating mitochondrial autophagy

Background:To investigate the pharmacological effects of Fangshi Jiangtang decoction(FSJT)on type 2 diabetes mellitus(T2DM)model rats and explore its mechanism of action from the perspective of mitochondrial autophagy.Methods:Sixty Sprague Dawley rats were randomly divided into six groups after one week of adaptive feeding:Control group,T2DM model group,metformin group(0.2 g/kg by gavage),and FSJT low,medium,and high dose groups(9.5,19,38 g/kg by gavage).Except for the Control group,the other five groups were given a high-fat diet.The treatment lasted for 8 weeks,and blood glucose levels were measured weekly.Eight weeks later,blood samples were collected from the rats,and serum was separated for the determination of HbA1c,oral glucose tolerance test,and homeostatic model assessment for insulin resistance index.The pancreas of the rats was collected,weighed,and fixed.The same part of the pancreas was used for hematoxylin-eosin.Kits were used to detect triglycerides,total cholesterol,interleukin-1β,interleukin-6,tumor necrosis factor-α,malondialdehyde,glutathione peroxidase,and superoxide dismutase in pancreatic tissue to assess the effects of FSJT on inflammation and oxidative stress in T2DM rats.Western blot analysis was performed to detect the expression of VDAC1,TOM20,COXⅣ,PINK1,Parkin,beclin1,light chain 3,and selective autophagy adaptor protein P62 to evaluate the effects of FSJT on mitochondrial autophagy in T2DM model rats.Results:Compared with the T2DM model group,FSJT intervention significantly reduced blood glucose,HbA1c,oral glucose tolerance test,and homeostatic model assessment for insulin resistance index in T2DM model rats,alleviated pancreatic tissue lesions,reduced levels of total cholesterol,triglycerides,interleukin-1β,interleukin-6,tumor necrosis factor-α,and malondialdehyde,increased glutathione peroxidase and superoxide dismutase activities,downregulated the expression of VDAC1,TOM20,COXⅣ,and P62 proteins,and upregulated the expression of PINK1,Parkin,Beclin1,and light chain 3 proteins.Conclusion:FSJT can improve insulin resistance in T2DM by promoting the activation of mitochondrial autophagy.

Sodium-glucose cotransporter-2 inhibitors protect tissues via cellular and mitochondrial pathways:Experimental and clinical evidence

Mitochondrial dysfunction is a key driver of cardiovascular disease(CVD)in metabolic syndrome and diabetes.This dysfunction promotes the production of reactive oxygen species(ROS),which cause oxidative stress and inflammation.Angiotensin II,the main mediator of the renin-angiotensin-aldosterone system,also contributes to CVD by promoting ROS production.Reduced activity of sirtuins(SIRTs),a family of proteins that regulate cellular metabolism,also worsens oxidative stress.Reduction of energy production by mitochondria is a common feature of all metabolic disorders.High SIRT levels and 5’adenosine monophosphate-activated protein kinase signaling stimulate hypoxia-inducible factor 1 beta,which promotes ketosis.Ketosis,in turn,increases autophagy and mitophagy,processes that clear cells of debris and protect against damage.Sodiumglucose cotransporter-2 inhibitors(SGLT2i),a class of drugs used to treat type 2 diabetes,have a beneficial effect on these mechanisms.Randomized clinical trials have shown that SGLT2i improves cardiac function and reduces the rate of cardiovascular and renal events.SGLT2i also increase mitochondrial efficiency,reduce oxidative stress and inflammation,and strengthen tissues.These findings suggest that SGLT2i hold great potential for the treatment of CVD.Furthermore,they are proposed as anti-aging drugs;however,rigorous research is needed to validate these preliminary findings.

Changes of mitochondrial dynamics during the progression of non-alcoholic fatty liver disease: a review

Non-alcoholic fatty liver disease(NAFLD)is a chronic liver disease closely related to metabolic disorders that pose a serious threat to human health.Currently,no specific drugs are available for treating the aetiology of NAFLD in clinical practice.Mitochondria have various biological functions inside the cell.Studies have found that mitochondrial fission and fusion are closely related to NAFLD.Therefore,identifying therapeutic targets for NAFLD through mitochondrial fission and fusion is crucial.Particularly in the field of traditional Chinese medicine,good therapeutic effects have been achieved in the treatment of NAFLD by protecting mitochondrial fusion and fission.Therefore,this article reviews the relationship between mitochondrial dynamics and NAFLD as well as the treatment of NAFLD through the regulation of mitochondrial fission and fusion with traditional Chinese medicine to provide a reference for the clinical application of traditional Chinese medicine in regulating mitochondrial fission and fusion functions to treat NAFLD.

Restoration of Mitochondrial Structure and Function within Helicobacter pylori VacA Intoxicated Cells

The Helicobacter pylori vacuolating cytotoxin (VacA) is an intracellular, mitochondrial-targeting exotoxin that rapidly causes mitochondrial dysfunction and fragmentation. Although VacA targeting of mitochondria has been reported to alter overall cellular metabolism, there is little known about the consequences of extended exposure to the toxin. Here, we describe studies to address this gap in knowledge, which have revealed that mitochondrial dysfunction and fragmentation are followed by a time-dependent recovery of mitochondrial structure, mitochondrial transmembrane potential, and cellular ATP levels. Cells exposed to VacA also initially demonstrated a reduction in oxidative phosphorylation, as well as increase in compensatory aerobic glycolysis. These metabolic alterations were reversed in cells with limited toxin exposure, congruent with the recovery of mitochondrial transmembrane potential and the absence of cytochrome c release from the mitochondria. Taken together, these results are consistent with a model that mitochondrial structure and function are restored in VacA-intoxicated cells.

Mitochondria in Huntington’s disease:implications in pathogenesis and mitochondrial-targeted therapeutic strategies

Huntington’s disease is a genetic disease caused by expanded CAG repeats on exon 1 of the huntingtin gene located on chromosome 4.Compelling evidence implicates impaired mitochondrial energetics,altered mitochondrial biogenesis and quality control,disturbed mitochondrial trafficking,oxidative stress and mitochondrial calcium dyshomeostasis in the pathogenesis of the disorder.Unfortunately,conventional mitochondrial-targeted molecules,such as cysteamine,creatine,coenzyme Q10,or triheptanoin,yielded negative or inconclusive results.However,future therapeutic strategies,aiming to restore mitochondrial biogenesis,improving the fission/fusion balance,and improving mitochondrial trafficking,could prove useful tools in improving the phenotype of Huntington’s disease and,used in combination with genome-editing methods,could lead to a cure for the disease.