Uterine Insulin Sensitivity Defects Induced Embryo Implantation Loss Associated with Mitochondrial Dysfunction-Triggered Oxidative Stress

Scope. Implantation loss is a considerable cause of early pregnancy loss in humans and mammalian animals. It is not addressed how proliferative uterine defects implicate in implantation loss. Methods and Results. Herein, a comprehensive proteomic analysis was conducted on proliferative endometria from sows with low and normal reproductive performance (LRP and NRP, respectively). Enrichment analysis of differentially expressed proteins revealed alterations in endometrial remodeling, substance metabolism (mainly lipid, nitrogen, and retinol metabolism), immunological modulation, and insulin signaling in LRP sows. Importantly, aberrant lipid metabolite accumulation and dysregulation of insulin signaling were coincidently confirmed in endometria of LPR sows, proving an impaired insulin sensitivity. Furthermore, established high-fat diet- (HFD-) induced insulin-resistant mouse models revealed that uterine insulin resistance beginning before pregnancy deteriorated uterine receptivity and decreased implantation sites and fetal numbers. Mitochondrial biogenesis and fusion were decreased, and reactive oxygen species was overproduced in uteri from the HFD group during the implantation period. Ishikawa and JAR cells directly demonstrated that oxidative stress compromised implantation in vitro. Conclusions. This study demonstrated that uterine insulin sensitivity impairment beginning before pregnancy resulted in implantation and fetal loss associated with oxidative stress induced by mitochondrial dysfunction.

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Metformin alleviates stress-induced cellular senescence of aging human adipose stromal cells and the ensuing adipocyte dysfunction

eLife ◽

10.7554/elife.62635 ◽

2021 ◽

Vol 10 ◽

Author(s):

Laura Le Pelletier ◽

Matthieu Mantecon ◽

Jennifer Gorwood ◽

Martine Auclair ◽

Roberta Foresti ◽

...

Keyword(s):

Oxidative Stress ◽

Insulin Sensitivity ◽

Mitochondrial Dysfunction ◽

Stromal Cells ◽

Subcutaneous Fat ◽

Normal Weight ◽

Young Donor ◽

Age Related ◽

Aged Donor

Aging is associated with central fat redistribution and insulin resistance. To identify age-related adipose features, we evaluated the senescence and adipogenic potential of adipose-derived-stromal cells (ASCs) from abdominal subcutaneous fat obtained from healthy normal-weight young (<25y) or older women (>60y). Increased cell passages of young-donor ASCs (in vitro aging), resulted in senescence but not oxidative stress. ASC-derived adipocytes presented impaired adipogenesis but no early mitochondrial dysfunction. Conversely, aged-donor ASCs at early passages displayed oxidative stress and mild senescence. ASC-derived adipocytes exhibited oxidative stress, and early mitochondrial dysfunction but adipogenesis was preserved. In vitro aging of aged-donor ASCs resulted in further increased senescence, mitochondrial dysfunction, oxidative stress and severe adipocyte dysfunction. When in vitro aged young-donor ASCs were treated with metformin, no alteration was alleviated. Conversely, metformin treatment of aged-donor ASCs decreased oxidative stress and mitochondrial dysfunction resulting in decreased senescence. Metformin's prevention of oxidative stress and of the resulting senescence improved the cells' adipogenic capacity and insulin sensitivity. This effect was mediated by the activation of AMP-activated-protein-kinase as revealed by its specific inhibition and activation. Overall, aging ASC-derived adipocytes presented impaired adipogenesis and insulin sensitivity. Targeting stress-induced senescence of ASCs with metformin may improve age-related adipose tissue dysfunction.

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Glycine ameliorates mitochondrial dysfunction caused by ABT-199 in porcine oocytes

Journal of Animal Science ◽

10.1093/jas/skab072 ◽

2021 ◽

Author(s):

Sicong Yu ◽

Lepeng Gao ◽

Yang Song ◽

Xin Ma ◽

Shuang Liang ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Oocyte Maturation ◽

Mitochondrial Function ◽

Protective Action ◽

Damage Model ◽

Developmental Competence ◽

Free Calcium ◽

Maturation In Vitro

Abstract Mitochondria play an important role in controlling oocyte developmental competence. Our previous studies showed that glycine can regulate mitochondrial function and improve oocyte maturation in vitro. However, the mechanisms by which glycine affects mitochondrial function during oocyte maturation in vitro have not been fully investigated. In this study, we induced a mitochondrial damage model in oocytes with the Bcl-2-specific antagonist ABT-199. We investigated whether glycine could reverse the mitochondrial dysfunction induced by ABT-199 exposure and whether it is related to calcium regulation. Our results showed that ABT-199 inhibited cumulus expansion, decreased the oocyte maturation rate and the intracellular glutathione (GSH) level, caused mitochondrial dysfunction, induced oxidative stress, which was confirmed by decreased mitochondrial membrane potential (Δ⍦m) and the expression of mitochondrial function-related genes (PGC-1α), and increased reactive oxygen species (ROS) levels and the expression of apoptosis-associated genes (Bax, caspase-3, CytC). More importantly, ABT-199-treated oocytes showed an increase in the intracellular free calcium concentration ([Ca 2+]i) and had impaired cortical type 1 inositol 1,4,5-trisphosphate receptors (IP3R1) distribution. Nevertheless, treatment with glycine significantly ameliorated mitochondrial dysfunction, oxidative stress and apoptosis, glycine also regulated [Ca 2+]i levels and IP3R1 cellular distribution, which further protects oocyte maturation in ABT-199-induced porcine oocytes. Taken together, our results indicate that glycine has a protective action against ABT-199-induced mitochondrial dysfunction in porcine oocytes.

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Neurotherapeutic Effect of Inula britannica var. Chinensis against H2O2-Induced Oxidative Stress and Mitochondrial Dysfunction in Cortical Neurons

Antioxidants ◽

10.3390/antiox10030375 ◽

2021 ◽

Vol 10 (3) ◽

pp. 375

Author(s):

Jin Young Hong ◽

Hyunseong Kim ◽

Junseon Lee ◽

Wan-Jin Jeon ◽

Seung Ho Baek ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Cortical Neurons ◽

Inflammatory Diseases ◽

Neuroprotective Effect ◽

Neuroprotective Effects ◽

Neuronal Viability ◽

Inula Britannica ◽

Oxidative Effects

Inula britannica var. chinensis (IBC) has been used as a traditional medicinal herb to treat inflammatory diseases. Although its anti-inflammatory and anti-oxidative effects have been reported, whether IBC exerts neuroprotective effects and the related mechanisms in cortical neurons remain unknown. In this study, we investigated the effects of different concentrations of IBC extract (5, 10, and 20 µg/mL) on cortical neurons using a hydrogen peroxide (H2O2)-induced injury model. Our results demonstrate that IBC can effectively enhance neuronal viability under in vitro-modeled reaction oxygen species (ROS)-generating conditions by inhibiting mitochondrial ROS production and increasing adenosine triphosphate level in H2O2-treated neurons. Additionally, we confirmed that neuronal death was attenuated by improving the mitochondrial membrane potential status and regulating the expression of cytochrome c, a protein related to cell death. Furthermore, IBC increased the expression of brain-derived neurotrophic factor and nerve growth factor. Furthermore, IBC inhibited the loss and induced the production of synaptophysin, a major synaptic vesicle protein. This study is the first to demonstrate that IBC exerts its neuroprotective effect by reducing mitochondria-associated oxidative stress and improving mitochondrial dysfunction.

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Regulation of Mitochondria-Associated Membranes (MAMs) by NO/sGC/PKG Participates in the Control of Hepatic Insulin Response

Cells ◽

10.3390/cells8111319 ◽

2019 ◽

Vol 8 (11) ◽

pp. 1319 ◽

Cited By ~ 5

Author(s):

Arthur Bassot ◽

Marie-Agnès Chauvin ◽

Nadia Bendridi ◽

Jingwei Ji-Cao ◽

Guillaume Vial ◽

...

Keyword(s):

Insulin Sensitivity ◽

Insulin Signaling ◽

Soluble Guanylate Cyclase ◽

Insulin Response ◽

Cyclophilin D ◽

Hepatic Insulin Sensitivity ◽

Physiological Conditions ◽

Huh7 Cells ◽

The Impact

Under physiological conditions, nitric oxide (NO) produced by the endothelial NO synthase (eNOS) upregulates hepatic insulin sensitivity. Recently, contact sites between the endoplasmic reticulum and mitochondria named mitochondria-associated membranes (MAMs) emerged as a crucial hub for insulin signaling in the liver. As mitochondria are targets of NO, we explored whether NO regulates hepatic insulin sensitivity by targeting MAMs. In Huh7 cells, primary rat hepatocytes and mouse livers, enhancing NO concentration increased MAMs, whereas inhibiting eNOS decreased them. In vitro, those effects were prevented by inhibiting protein kinase G (PKG) and mimicked by activating soluble guanylate cyclase (sGC) and PKG. In agreement with the regulation of MAMs, increasing NO concentration improved insulin signaling, both in vitro and in vivo, while eNOS inhibition disrupted this response. Finally, inhibition of insulin signaling by wortmannin did not affect the impact of NO on MAMs, while experimental MAM disruption, using either targeted silencing of cyclophilin D or the overexpression of the organelle spacer fetal and adult testis-expressed 1 (FATE-1), significantly blunted the effects of NO on both MAMs and insulin response. Therefore, under physiological conditions, NO participates to the regulation of MAM integrity through the sGC/PKG pathway and concomitantly improves hepatic insulin sensitivity. Altogether, our data suggest that the induction of MAMs participate in the impact of NO on hepatocyte insulin response.

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CORTISOL CIRCADIAN RHYTHM AND INSULIN RESISTANCE IN MUSCLE: EFFECT OF DOSING AND TIMING OF HYDROCORTISONE EXPOSURE ON INSULIN SENSITIVITY IN SYNCHRONIZED MUSCLE CELLS.

Neuroendocrinology ◽

10.1159/000512685 ◽

2020 ◽

Author(s):

Mariarosaria Negri ◽

Claudia Pivonello ◽

Chiara Simeoli ◽

Gilda Di Gennaro ◽

Mary Anna Venneri ◽

...

Keyword(s):

Skeletal Muscle ◽

Circadian Rhythm ◽

Insulin Sensitivity ◽

Circadian Clock ◽

Insulin Signaling ◽

Clock Genes ◽

Muscle Cells ◽

C2c12 Cells ◽

Circadian Expression

Introduction/Aim: Circadian rhythm disruption is emerging as a risk factor for metabolic disorders and particularly, alterations in clock genes circadian expression have been shown to influence insulin sensitivity. Recently, the reciprocal interplay between the circadian clock machinery and HPA axis has been largely demonstrated: the circadian clock may control the physiological circadian endogenous glucocorticoids secretion and action; glucocorticoids, in turn, are potent regulator of the circadian clock and their inappropriate replacement has been associated with metabolic impairment. The aim of the current study was to investigate in vitro the interaction between the timing-of-the-day exposure to different hydrocortisone (HC) concentrations on muscle insulin sensitivity. Methods: Serum-shock synchronized mouse skeletal muscle C2C12 cells were exposed to different HC concentrations recapitulating the circulating daily physiological cortisol profile (standard cortisol profile), the circulating daily cortisol profile that reached in adrenal insufficient (AI) patients treated with once-daily MR-HC (flat cortisol profile) and treated with thrice-daily of conventional IR-HC (steep cortisol profile). The 24 hrs spontaneous oscillation of the clock genes in synchronized C2C12 cells was used to align the timing for in vitro HC exposure (Bmal1 acrophase, midphase and bathyphase) with the reference times of cortisol peaks in AI treated with IR-HC (8 am, 1 pm, 6 pm). A panel of 84 insulin sensitivity related genes and intracellular insulin signaling proteins were analyzed by RT-qPCR and western blot, respectively. Results: Only the steep profile, characterized by a higher HC exposure during Bmal1 bathyphase, produced significant downregulation in 21 insulin sensitivity-related genes. Among these, Insr, Irs1, Irs2, Pi3kca and Adipor2 were downregulated when compared the flat to the standard or steep profile. Reduced intracellular IRS1 Tyr608, AKT Ser473, AMPK Thr172 and ACC Ser79 phosphorylations were also observed. Conclusions: The current study demonstrated that is late-in-the-day cortisol exposure that modulates insulin sensitivity-related genes expression and intracellular insulin signaling in skeletal muscle cells.

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Honeybush Extracts (Cyclopia spp.) Rescue Mitochondrial Functions and Bioenergetics against Oxidative Injury

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/1948602 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Anastasia Agapouda ◽

Veronika Butterweck ◽

Matthias Hamburger ◽

Dalene de Beer ◽

Elizabeth Joubert ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Hot Water ◽

Human Neuroblastoma ◽

Atp Production ◽

Physiological Conditions ◽

Age Related ◽

Mitochondrial Functions ◽

Scientific Attention

Mitochondrial dysfunction plays a major role not only in the pathogenesis of many oxidative stress or age-related diseases such as neurodegenerative as well as mental disorders but also in normal aging. There is evidence that oxidative stress and mitochondrial dysfunction are the most upstream and common events in the pathomechanisms of neurodegeneration. Cyclopia species are endemic South African plants and some have a long tradition of use as herbal tea, known as honeybush tea. Extracts of the tea are gaining more scientific attention due to their phenolic composition. In the present study, we tested not only the in vitro mitochondria-enhancing properties of honeybush extracts under physiological conditions but also their ameliorative properties under oxidative stress situations. Hot water and ethanolic extracts of C. subternata, C. genistoides, and C. longifolia were investigated. Pretreatment of human neuroblastoma SH-SY5Y cells with honeybush extracts, at a concentration range of 0.1-1 ng/ml, had a beneficial effect on bioenergetics as it increased ATP production, respiration, and mitochondrial membrane potential (MMP) after 24 hours under physiological conditions. The aqueous extracts of C. subternata and C. genistoides, in particular, showed a protective effect by rescuing the bioenergetic and mitochondrial deficits under oxidative stress conditions (400 μM H2O2 for 3 hours). These findings indicate that honeybush extracts could constitute candidates for the prevention of oxidative stress with an impact on aging processes and age-related neurodegenerative disorders potentially leading to the development of a condition-specific nutraceutical.

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Mitochondrial dysfunction induced by high estradiol concentrations in endometrial epithelial cells

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem/dgz015 ◽

2019 ◽

Author(s):

Chia-Hung Chou ◽

Shee-Uan Chen ◽

Chin-Der Chen ◽

Chia-Tung Shun ◽

Wen-Fen Wen ◽

...

Keyword(s):

Epithelial Cells ◽

Mitochondrial Dysfunction ◽

Embryo Implantation ◽

Ros Production ◽

Vitro Fertilization ◽

Equine Chorionic Gonadotropin ◽

In Vivo Effects ◽

Endometrial Epithelial Cells

Abstract Context A supraphysiological estradiol (E2) concentration after ovarian stimulation is known to result in lower embryo implantation rates in in vitro fertilization (IVF). Endometrial epithelial cells (EECs) apoptosis occurs after the stimulation with high E2 concentrations, and mitochondria play important roles in cell apoptosis. Objective To investigate the mitochondrial function in EECs after the stimulation with high E2 concentrations. Materials and Methods Human EECs were purified and cultured with different E2 concentrations (10-10, 10-9, 10-8, 10-7 M) in vitro, in which 10-7 M is supraphysiologically high. Eight-week-old female mouse endometrium was obtained 5.5 days after the injection of 1.25 IU or 20 IU equine chorionic gonadotropin (eCG), roughly during the embryo implantation window, to examine the in vivo effects of high E2 concentrations on mouse EECs. Results In vivo and in vitro experiments demonstrated decreased mitochondrial DNA contents and ATP formation after EECs were stimulated with supraphysiologically high E2 concentrations than those stimulated with a physiologic E2 concentration. Less prominent immunofluorescence mitochondrial staining, fewer mitochondria number under electron microscopy, lower JC-1 aggregate/monomer ratio, and greater reactive oxygen species (ROS) production were found after EECs were stimulated with supraphysiologically high E2 concentrations. The high E2-induced ROS production was reduced when EECs were pretreated with N-acetyl-cysteine (NAC) in vitro, but remained unchanged after the pretreatment with coenzyme Q10. Conclusion High E2 concentrations increase extra-mitochondrial ROS production in EECs and subsequently result in mitochondrial dysfunction.

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Mitochondrial Dysfunction Induced by High Estradiol Concentrations in Endometrial Epithelial Cells

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgz015 ◽

2019 ◽

Vol 105 (1) ◽

pp. 126-135 ◽

Cited By ~ 1

Author(s):

Chia-Hung Chou ◽

Shee-Uan Chen ◽

Chin-Der Chen ◽

Chia-Tung Shun ◽

Wen-Fen Wen ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Embryo Implantation ◽

Ros Production ◽

Vitro Fertilization ◽

Endometrial Epithelial Cell ◽

Dna Contents ◽

Equine Chorionic Gonadotropin ◽

In Vivo Effects

Abstract Context A supraphysiological estradiol (E2) concentration after ovarian stimulation is known to result in lower embryo implantation rates in in vitro fertilization. Endometrial epithelial cell (EEC) apoptosis occurs after the stimulation with high E2 concentrations, and mitochondria play important roles in cell apoptosis. Objective To investigate the mitochondrial function in EECs after the stimulation with high E2 concentrations. Materials and Methods Human EECs were purified and cultured with different E2 concentrations (10-10, 10–9, 10–8, 10–7 M) in vitro, in which 10–7 M is supraphysiologically high. Eight-week-old female mouse endometrium was obtained 5.5 days after the injection of 1.25 IU or 20 IU equine chorionic gonadotropin, roughly during the embryo implantation window, to examine the in vivo effects of high E2 concentrations on mouse EECs. Results In vivo and in vitro experiments demonstrated decreased mitochondrial DNA contents and ATP formation after EECs were stimulated with supraphysiologically high E2 concentrations than those stimulated with a physiologic E2 concentration. Less prominent immunofluorescence mitochondrial staining, fewer mitochondria numbers under electron microscopy, lower 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyanine iodide aggregate/monomer ratio, and greater reactive oxygen species (ROS) production were found after EECs were stimulated with supraphysiologically high E2 concentrations. The high E2-induced ROS production was reduced when EECs were pretreated with N-acetyl-cysteine in vitro, but remained unchanged after the pretreatment with coenzyme Q10. Conclusion High E2 concentrations increase extramitochondrial ROS production in EECs and subsequently result in mitochondrial dysfunction.

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The Niemann-Pick C1 Like 1 (NPC1L1) Inhibitor Ezetimibe Improves Metabolic Disease Via Decreased Liver X Receptor (LXR) Activity in Liver of Obese Male Mice

Endocrinology ◽

10.1210/en.2013-2143 ◽

2014 ◽

Vol 155 (8) ◽

pp. 2810-2819 ◽

Cited By ~ 20

Author(s):

Taichi Sugizaki ◽

Mitsuhiro Watanabe ◽

Yasushi Horai ◽

Nao Kaneko-Iwasaki ◽

Eri Arita ◽

...

Keyword(s):

Oxidative Stress ◽

Metabolic Syndrome ◽

Insulin Signaling ◽

Metabolic Diseases ◽

In Vitro Study ◽

Liver X Receptor ◽

Gene Expressions ◽

The Metabolic Syndrome ◽

Increased Risk

Dyslipidemic patients with diabetes mellitus, including metabolic syndrome, are at increased risk of coronary heart disease. It has been reported that ezetimibe, a cholesterol absorption inhibitor, improves metabolic diseases in mice and humans. However, the underlying mechanism has been unclear. Here we explored the effects of ezetimibe on lipid and glucose homeostasis. Male KK-Ay mice were fed a high-fat diet, which is the mouse model of metabolic syndrome, with or without ezetimibe for 14 weeks. Ezetimibe improved dyslipidemia, steatosis, and insulin resistance. Ezetimibe decreased hepatic oxysterols, which are endogenous agonists of liver X receptor (LXR), to decrease hepatic lipogenic gene expressions, especially in stearoyl-CoA desaturase-1 (SCD1), leading to a remarkable reduction of hepatic oleate content that would contribute to the improvement of steatosis by reducing triglycerides and cholesterol esters. Simultaneously, hepatic β-oxidation, NADPH oxidase and cytochrome P450 2E1 (CYP2E1) were reduced, and thus reactive oxygen species (ROS) and inflammatory cytokines were also decreased. Consistent with these changes, ezetimibe diminished c-Jun N-terminal kinase (JNK) phosphorylation and improved insulin signaling in the liver. In vitro study using primary hepatocytes obtained from male SD rats, treated with oleate and LXR agonist, showed excess lipid accumulation, increased oxidative stress and impaired insulin signaling. Therefore, in obese subjects, ezetimibe reduces hepatic LXR activity by reducing hepatic oxysterols to lower hepatic oleate content. This improves steatosis and reduces oxidative stress, and this reduction improves insulin signaling in the liver. These results provide insight into pathogenesis and strategies for treatment of the metabolic syndrome.

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Allicin Protects PC12 Cells Against 6-OHDA-Induced Oxidative Stress and Mitochondrial Dysfunction via Regulating Mitochondrial Dynamics

Cellular Physiology and Biochemistry ◽

10.1159/000430271 ◽

2015 ◽

Vol 36 (3) ◽

pp. 966-979 ◽

Cited By ~ 44

Author(s):

Hao Liu ◽

Ping Mao ◽

Jia Wang ◽

Tuo Wang ◽

Chang-Hou Xie

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Pc12 Cells ◽

Atp Synthesis ◽

Ros Generation ◽

Antioxidant Enzyme Activities ◽

Protective Effects ◽

Cytochrome C Release ◽

Endogenous Antioxidant

Background: Parkinson disease (PD) is a common adult-onset neurodegenerative disorder, and PD related neuronal injury is associated with oxidative stress and mitochondrial dysfunction. Allicin, the main biologically active compound derived from garlic, has been shown to exert various anti-oxidative and anti-apoptotic activities in in vitro and in vivo studies. Methods: The present study aimed to investigate the potential protective role of allicin in an in vitro PD model induced by 6-hydroxydopamine (6-OHDA) in PC12 cells. The protective effects were measured by cell viability, decreased lactate dehydrogenase (LDH) release and flow cytometry, and the anti-oxidative activity was determined by reactive oxygen species (ROS) generation, lipid peroxidation and the endogenous antioxidant enzyme activities. Mitochondrial function in PC12 cells was detected by mitochondrial membrane potential (MMP) collapse, cytochrome c release, mitochondrial ATP synthesis, and the mitochondrial Ca2+ buffering capacity. To investigate the potential mechanism, we also measured the expression of mitochondrial biogenesis factors, mitochondrial morphological dynamic changes, as well as detected mitochondrial dynamic proteins by western blot. Results: We found that allicin treatment significant increased cell viability, and decreased LDH release and apoptotic cell death after 6-OHDA exposure. Allicin also inhibited ROS generation, reduced lipid peroxidation and preserved the endogenous antioxidant enzyme activities. These protective effects were associated with suppressed mitochondrial dysfunction, as evidenced by decreased MMP collapse and cytochrome c release, preserved mitochondrial ATP synthesis, and the promotion of mitochondrial Ca2+ buffering capacity. In addition, allicin significantly enhanced mitochondrial biogenesis and prevented fragmentation of mitochondrial network after 6-OHDA treatment. The results of western blot analysis showed that the 6-OHDA induced decrease in the expression of optic atrophy type 1 (Opa-1), increase in mitochondrial fission 1 (Fis-1) and dynamin-related protein 1 (Drp-1) were all partially revised by allicin. Conclusion: In summary, our data strongly suggested that allicin treatment can exert protective effects against PD related neuronal injury through inhibiting oxidative stress and mitochondrial dysfunction with dynamic changes.

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