20 results on '"Kim, Myeong Ok"'
Search Results
2. Retraction Note: Gintonin Mitigates MPTP-Induced Loss of Nigrostriatal Dopaminergic Neurons and Accumulation of α-Synuclein via the Nrf2/HO-1 Pathway.
- Author
-
Jo, Min Gi, Ikram, Muhammad, Jo, Myeung Hoon, Yoo, Lang, Chung, Kwang Chul, Nah, Seung-Yeol, Hwang, Hongik, Rhim, Hyewhon, and Kim, Myeong Ok
- Published
- 2024
- Full Text
- View/download PDF
3. Antioxidative and Anti-inflammatory Effects of Kojic Acid in Aβ-Induced Mouse Model of Alzheimer's Disease.
- Author
-
Khan, Amjad, Park, Tae Ju, Ikram, Muhammad, Ahmad, Sareer, Ahmad, Riaz, Jo, Min Gi, and Kim, Myeong Ok
- Abstract
Alzheimer's disease (AD) is a common cause of dementia that is clinically characterized by the loss of memory and cognitive functions. Currently, there is no specific cure for the management of AD, although natural compounds are showing promising therapeutic potentials because of their safety and easy availability. Herein, we evaluated the neuroprotective properties of kojic acid (KA) in an AD mouse model. Intracerebroventricular injection (i.c.v) of Aβ
1-42 (5 μL/5 min/mouse) into wild-type adult mice induced AD-like pathological changes in the mouse hippocampus by increasing oxidative stress and neuroinflammation, affecting memory and cognitive functions. Interestingly, oral treatment of kojic acid (50 mg/kg/mouse for 3 weeks) reversed the AD pathology by reducing the expression of amyloid-beta (Aβ) and beta-site amyloid precursor protein cleaving enzyme1 (BACE-1). Moreover, kojic acid reduced oxidative stress by enhancing the expression of nuclear factor erythroid-related factor 2 (Nrf2) and heme oxygenase 1 (HO1). Also, kojic acid reduced the lipid peroxidation and reactive oxygen species in the Aβ + kojic acid co-treated mice brains. Moreover, kojic acid decreased neuroinflammation by inhibiting Toll-like receptor 4, phosphorylated nuclear factor-κB, tumor necrosis factor-alpha, interleukin 1-beta (TLR-4, p-NFκB, TNFα, and IL-1β, respectively), and glial cells. Furthermore, kojic acid enhanced synaptic markers (SNAP-23, SYN, and PSD-95) and memory functions in AD model mice. Additionally, kojic acid treatment also decreased Aβ expression, oxidative stress, and neuroinflammation in vitro in HT-22 mouse hippocampal cells. To the best of our knowledge, this is the first study to show the neuroprotective effects of kojic acid against an AD mouse model. Our findings could serve as a favorable and alternative strategy for the discovery of novel drugs to treat AD-related neurodegenerative conditions. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
4. Diagnosis of Unusual Case of Dysphagia with Macroglossia and Rigid Tongue.
- Author
-
Ryu, Hyeong, Kim, Su-Hong, Park, Ji-Sun, Park, Chan-Hyuk, Kim, Myeong-Ok, Kim, Chang-Hwan, Jung, Han-Young, and Joa, Kyung-Lim
- Published
- 2021
- Full Text
- View/download PDF
5. Hesperetin Confers Neuroprotection by Regulating Nrf2/TLR4/NF-κB Signaling in an Aβ Mouse Model.
- Author
-
Ikram, Muhammad, Muhammad, Tahir, Rehman, Shafiq Ur, Khan, Amjad, Jo, Min Gi, Ali, Tahir, and Kim, Myeong Ok
- Abstract
Hesperetin is a bioactive flavonoid in the body, produced from hesperidin. No comprehensive studies have shown its protective effects in neurodegenerative disorders. Here, we hypothesized that hesperetin may protect the mice brain against Aβ-induced neurodegeneration. Twenty-four hours after intracerebroventricular injection of Aβ1-42, the treated group was injected hesperetin. For in vitro experiments, HT22 and BV-2 cells were used. Immunoblot, immunofluorescence, and behavioral analyses were used to evaluate the different parameters. Our results indicated that hesperetin significantly attenuated oxidative stress, as assessed by the expression of Nrf2/HO-1 and LPO and ROS assays, in the hippocampus, cortex, and in vitro HT22 cells. Similarly, activated glial cells were regulated by hesperetin, as assessed by the expression of GFAP and Iba-1. Moreover, the expression of TLR4, p-NF-κB, and downstream targets was analyzed; the results showed that hesperetin reinstated the expression of these markers. The effects of hesperetin were further confirmed by using specific TLR4 and p-NF-κB inhibitors in BV-2 cells. Next, we evaluated Aβ pathology in the cortex, hippocampus, and HT22 cells, showing that hesperetin significantly reduced the Aβ pathology. Furthermore, the antiapoptotic effects of hesperetin were assessed, which showed strong antiapoptotic effects. Overall, the neuroprotective effect of hesperetin was found to be a multipotent effect, involving the inhibition of oxidative stress, neuroinflammation, apoptotic cell death, and cognitive consolidation. Given antioxidant, anti-inflammatory, and antiapoptotic potentials against Aβ-induced neurodegeneration and memory impairment, hesperetin may be a promising therapeutic agent for Alzheimer's disease–like neurological disorders. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
6. Melatonin Rescue Oxidative Stress-Mediated Neuroinflammation/ Neurodegeneration and Memory Impairment in Scopolamine-Induced Amnesia Mice Model.
- Author
-
Muhammad, Tahir, Ali, Tahir, Ikram, Muhammad, Khan, Amjad, Alam, Sayed Ibrar, and Kim, Myeong Ok
- Abstract
Cognitive decline and memory impairment induced by oxidative brain damage are the critical pathological hallmarks of Alzheimer's disease (AD). Based on the potential neuroprotective effects of melatonin, we here explored the possible underlying mechanisms of the protective effect of melatonin against scopolamine-induced oxidative stress-mediated c-Jun N-terminal kinase (JNK) activation, which ultimately results in synaptic dysfunction, neuroinflammation, and neurodegeneration. According to our findings, scopolamine administration resulted in LPO and ROS generation and decreased the protein levels of antioxidant proteins such as Nrf2 and HO-1; however, melatonin co-treatment mitigated the generation of oxidant factors while improving antioxidant protein levels. Similarly, melatonin ameliorated oxidative stress-mediated JNK activation, enhanced Akt/ERK/CREB signaling, promoted cell survival and proliferation, and promoted memory processes. Immunofluorescence and western blot analysis indicated that melatonin reduced activated gliosis via attenuation of Iba-1 and GFAP. We also found that scopolamine promoted neuronal loss by inducing Bax, Pro-Caspase-3, and Caspase-3 and reducing the levels of the antiapoptotic protein Bcl-2. In contrast, melatonin significantly decreased the levels of apoptotic markers and increased neuronal survival. We further found that scopolamine disrupted synaptic integrity and, conversely, that melatonin enhanced synaptic integrity as indicated by Syntaxin, PSD-95, and SNAP-23 expression levels. Furthermore, melatonin ameliorated scopolamine-induced impairments in spatial learning behavior and memory formation. On the whole, our findings revealed that melatonin attenuated scopolamine-induced synaptic dysfunction and memory impairments by ameliorating oxidative brain damage, stress kinase expression, neuroinflammation, and neurodegeneration. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
7. Ferulic Acid Rescues LPS-Induced Neurotoxicity via Modulation of the TLR4 Receptor in the Mouse Hippocampus.
- Author
-
Rehman, Shafiq Ur, Ali, Tahir, Alam, Sayed Ibrar, Ullah, Rahat, Zeb, Amir, Lee, Keun Woo, Rutten, Bart P. F., and Kim, Myeong Ok
- Abstract
Microglia play a crucial role in the inflammatory brain response to infection. However, overactivation of microglia is neurotoxic. Toll-like receptor 4 (TLR4) is involved in microglial activation via lipopolysaccharide (LPS), which triggers a variety of cytotoxic pro-inflammatory markers that produce deleterious effects on neuronal cells. Ferulic acid (FA) is a phenolic compound that exerts antioxidant and anti-inflammatory effects in neurodegenerative disease. However, the manner in which FA inhibits neuroinflammation-induced neurodegeneration is poorly understood. Therefore, we investigated the anti-inflammatory effects of FA against LPS-induced neuroinflammation in the mouse brain. First, we provide evidence that FA interferes with TLR4 interaction sites, which are required for the activation of microglia-induced neuroinflammation, and further examined the potential mechanism of its neuroprotective effects in the mouse hippocampus using molecular docking simulation and immunoblot analysis. Our results indicated that FA treatment inhibited glial cell activation, p-JNK, p-NF
K B, and downstream signaling molecules, such as iNOS, COX-2, TNF-α, and IL-1β, in the mouse hippocampus and BV2 microglial cells. FA treatment strongly inhibited mitochondrial apoptotic signaling molecules, such as Bax, cytochrome C, caspase-3, and PARP-1, and reversed deregulated synaptic proteins, including PSD-95, synaptophysin, SNAP-25, and SNAP-23, and synaptic dysfunction in LPS-treated mice. These findings demonstrated that FA treatment interfered with the TLR4/MD2 complex binding site, which is crucial for evoking neuroinflammation via microglia activation and inhibited NFK B likely via a JNK-dependent mechanism, which suggests a therapeutic implication for neuroinflammation-induced neurodegeneration. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
8. Anthocyanins Improve Hippocampus-Dependent Memory Function and Prevent Neurodegeneration via JNK/Akt/GSK3β Signaling in LPS-Treated Adult Mice.
- Author
-
Khan, Muhammad Sohail, Ali, Tahir, Kim, Min Woo, Jo, Myeung Hoon, Chung, Jong Il, and Kim, Myeong Ok
- Abstract
Microglia plays a critical role in the brain and protects neuronal cells from toxins. However, over-activation of microglia leads to deleterious effects. Lipopolysaccharide (LPS) has been reported to affect neuronal cells via activation of microglia as well as directly to initiate neuroinflammation. In the present study, we evaluated the anti-inflammatory and anti-oxidative effect of anthocyanins against LPS-induced neurotoxicity in an animal model and in cell cultures. Intraperitoneal injections of LPS (250 μg/kg/day for 1 week) induce ROS production and promote neuroinflammation and neurodegeneration which ultimately leads to memory impairment. However, anthocyanins treatment at a dose of 24 mg/kg/day for 2 weeks (1 week before and 1 week co-treated with LPS) prevented ROS production, inhibited neuroinflammation and neurodegeneration, and improved memory functions in LPS-treated mice. Both histological and immunoblot analysis indicated that anthocyanins reversed the activation of JNK, prevented neuroinflammation by lowering the levels of inflammatory markers (p-NF-kB, TNF-α, and IL-1β), and reduced neuronal apoptosis by reducing the expression of Bax, cytochrome c, cleaved caspase-3, and cleaved PARP-1, while increasing the level of survival proteins p-Akt, p-GSK3β, and anti-apoptotic Bcl-2 protein. Anthocyanins treatment increased the levels of memory-related pre- and post-synaptic proteins and improved the hippocampus-dependent memory in the LPS-treated mice. Overall, this data suggested that consumption of naturally derived anti-oxidant agent such as anthocyanins ameliorated several pathological events in the LPS-treated animal model and we believe that anthocyanins would be a safe therapeutic agent for slowing the inflammation-induced neurodegeneration in the brain against several diseases such as Alzheimer's disease and Parkinson's disease. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
9. Gintonin Mitigates MPTP-Induced Loss of Nigrostriatal Dopaminergic Neurons and Accumulation of α-Synuclein via the Nrf2/HO-1 Pathway.
- Author
-
Jo, Min Gi, Ikram, Muhammad, Jo, Myeung Hoon, Yoo, Lang, Chung, Kwang Chul, Nah, Seung-Yeol, Hwang, Hongik, Rhim, Hyewhon, and Kim, Myeong Ok
- Abstract
Gintonin, a ginseng-derived glycolipoprotein isolated from ginseng, has been shown to be neuroprotective in several neurological disorders such as Alzheimer's disease models and depressive-like behaviors. In this study, we sought to investigate the potential protective mechanisms of gintonin in an in vivo MPTP and in vitro MPP
+ -mediated Parkinson's disease (PD) model. We hypothesized that activation of nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1, potential therapeutic targets for neurodegeneration) with gintonin could abrogate PD-associated neurotoxicity by modulating the accumulation of α-synuclein, neuroinflammation, and apoptotic cell death in an MPTP/MPP+ models of PD. Our in vivo and in vitro findings suggest that the neuroprotective effects of gintonin were associated with the regulation of the Nrf2/HO-1 pathway, which regulated the expression of proinflammatory cytokines and nitric oxide synthase and apoptotic markers in the substantia nigra and striatum of the mice. Moreover, the neuroprotective effects of gintonin were also associated with a reduction in α-synuclein accumulation in the mouse substantia nigra and striatum. The neuroprotective effects of gintonin were further validated by analyzing the effects of gintonin on MPP+ -treated SH-SY5Y cells, which confirmed the protective effects of gintonin. It remains for future basic and clinical research to determine the potential use of gintonin in Parkinson's disease. However, to the best of our knowledge, marked alterations in biochemical and morphological setup of midbrain dopaminergic pathways by gintonin in MPTP mice model have not been previously reported. We believe that gintonin might be explored as an important therapeutic agent in the treatment of PD. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
10. The Adiponectin Homolog Osmotin Enhances Neurite Outgrowth and Synaptic Complexity via AdipoR1/NgR1 Signaling in Alzheimer’s Disease.
- Author
-
Yoon, Gwangho, Shah, Shahid Ali, Ali, Tahir, and Kim, Myeong Ok
- Abstract
Alzheimer’s disease is a major neurodegenerative disease characterized by memory loss and cognitive deficits. Recently, we reported that osmotin, which is a homolog of adiponectin, improved long-term potentiation and cognitive functions in Alzheimer’s disease mice. Several lines of evidence have suggested that Nogo-A and the Nogo-66 receptor 1 (NgR1), which form a complex that inhibits long-term potentiation and cognitive function, might be associated with the adiponectin receptor 1 (AdipoR1), which is a receptor for osmotin. Here, we explore whether osmotin’s effects on long-term potentiation and memory function are associated with NgR1 signaling via AdipoR1 in Alzheimer’s disease. Osmotin reduced the expression of NgR1 without affecting Nogo-A expression. Furthermore, osmotin inhibited NgR1 signaling by prohibiting the formation of the Nogo-A and NgR1 ligand-receptor complex, resulting in enhanced neurite outgrowth; these effects disappeared in the presence of AdipoR1 interference. In addition, osmotin increased the expression of the pre- and postsynaptic markers synaptophysin and PSD-95, as well as the activation of the memory-associated markers AMPA receptor and CREB; these effects occurred in an AdipoR1- and NgR1-dependent manner. Osmotin was also found to enhance dendritic complexity and spine density in the hippocampal region of Alzheimer’s disease mouse brains. These results suggest that osmotin can enhance neurite outgrowth and synaptic complexity through AdipoR1 and NgR1 signaling, implying that osmotin might be an effective therapeutic agent for Alzheimer’s disease and that AdipoR1 might be a crucial therapeutic target for neurodegenerative diseases such as Alzheimer’s. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
11. Natural Dietary Supplementation of Anthocyanins via PI3K/Akt/Nrf2/HO-1 Pathways Mitigate Oxidative Stress, Neurodegeneration, and Memory Impairment in a Mouse Model of Alzheimer’s Disease.
- Author
-
Ali, Tahir, Kim, Taehyun, Rehman, Shafiq Ur, Khan, Muhammad Sohail, Amin, Faiz Ul, Khan, Mehtab, Ikram, Muhammad, and Kim, Myeong Ok
- Abstract
Well-established studies have shown an elevated level of reactive oxygen species (ROS) that induces oxidative stress in the Alzheimer’s disease (AD) patient’s brain and an animal model of AD. Herein, we investigated the underlying anti-oxidant neuroprotective mechanism of natural dietary supplementation of anthocyanins extracted from Korean black beans in the amyloid precursor protein/presenilin-1 (APP/PS1) mouse model of AD. Both in vivo (APP/PS1 mice) and in vitro (mouse hippocampal HT22 cells) results demonstrated that anthocyanins regulate the phosphorylated-phosphatidylinositol 3-kinase-Akt-glycogen synthase kinase 3 beta (p-PI3K/Akt/GSK3β) pathways and consequently attenuate amyloid beta oligomer (AβO)-induced elevations in ROS level and oxidative stress via stimulating the master endogenous anti-oxidant system of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (Nrf2/HO-1) pathways and prevent apoptosis and neurodegeneration by suppressing the apoptotic and neurodegenerative markers such as activation of caspase-3 and PARP-1 expression as well as the TUNEL and Fluoro-Jade B-positive neuronal cells in the APP/PS1 mice. In vitro ApoTox-Glo™ Triplex assay results also showed that anthocyanins act as a potent anti-oxidant neuroprotective agent and reduce AβO-induced neurotoxicity in the HT22 cells via PI3K/Akt/Nrf2 signaling. Importantly, anthocyanins improve memory-related pre- and postsynaptic protein markers and memory functions in the APP/PS1 mice. In conclusion, our data suggested that consumption and supplementation of natural-derived anti-oxidant neuroprotective agent such as anthocyanins may be beneficial and suggest new dietary-supplement strategies for intervention in and prevention of progressive neurodegenerative diseases, such as AD. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
12. 17β-Estradiol via SIRT1/Acetyl-p53/NF-kB Signaling Pathway Rescued Postnatal Rat Brain Against Acute Ethanol Intoxication.
- Author
-
Khan, Mehtab, Shah, Shahid Ali, and Kim, Myeong Ok
- Abstract
Growing evidences reveal that 17β-estradiol has a wide variety of neuroprotective potential. Recently, it has been shown that 17β-estradiol can limit ethanol-induced neurotoxicity in neonatal rats. Whether it can stimulate SIRT1 signaling against ethanol intoxicity in developing brain remain elusive. Here, we report for the first time that 17β-estradiol activated SIRT1 to deacetylate p53 proteins against acute ethanol-induced oxidative stress, neuroinflammation, and neurodegeneration. A single subcutaneous injection of ethanol-induced oxidative stress triggered phospho c-jun N terminal kinase (p-JNK) and phospho mammalian target of rapamycin (p-mTOR) accompanied by neuroinflammation and widespread neurodegeneration. In contrast, 17β-estradiol cotreatment positively regulated SIRT1, inhibited p53 acetylation, reactive oxygen species (ROS) production, p-JNK, and p-mTOR activation and reduced neuroinflammation and neuronal cell death in the postnatal rat brain. Interestingly, SIRT1 inhibition with its inhibitor, i.e., EX527 further enhanced ethanol intoxication and also abolished the beneficial effects of 17β-estradiol against ethanol in the young rat’s brain. Indeed, 17β-estradiol treatment increased the cell viability (HT22 cells), inhibited ROS production via the SIRT1/Acetyl-p53 pathway, and reduced the nuclear translocation of phospho-nuclear factor kappa B (p-NF-kB) in the BV2 microglia cells. Taken together, these results show that 17β-estradiol can be used as a potential neuroprotective agent against acute ethanol intoxication. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
13. Neuro Invasive Multi-targeted Drug Delivery Approach Using Swarm of Nano-robotic Carriers.
- Author
-
Hassan, Syed, Ullah, Ikram, Kim, Myeong Ok, and Yoon, Jungwon
- Published
- 2013
- Full Text
- View/download PDF
14. Hedgehog Signaling Between Cancer Cells and Hepatic Stellate Cells in Promoting Cholangiocarcinoma.
- Author
-
Kim, Younjoo, Kim, Myeong-ok, Shin, Jin, Park, Sun, Kim, Sang, Kim, Jin, Park, Su, Han, Chul, Ryu, Ji, Yoon, Yong, and Kim, Yong-Tae
- Abstract
Background: Aberrant Hedgehog (HH) signaling activation is important in cancer growth and mediates the interaction between cancer cells and the surrounding stromal cells. This study investigated the role of HH signaling on the growth of cholangiocarcinoma (CC), focusing on the interaction of CC cells with stromal cells. Methods: To evaluate the interaction between human CC cells (SNU-1196, SNU-246, SNU-308, SNU-1079, and HuCCT-1) and stromal cells (hepatic stellate cell line, Lx-2), co-culture proliferation, migration, and invasion assays were performed. In vivo nude mice experiments were conducted using two groups-HuCCT-1 single implant xenograft (SX) and co-implant xenograft (CX) with HuCCT-1 and Lx-2. Results: When HuCCT-1 cells were co-cultured with Lx-2 cells, the expression of HH signaling-related proteins increased in both HuCCT-1 and Lx-2 cells. Co-culture with Lx-2 cells stimulated the proliferation, migration, and invasion of CC cells, and these effects were mediated by HH signaling. Co-culture of HuCCT-1 and Lx-2 cells increased the secretion of several cytokines. In an ectopic xenograft model, Lx-2 co-implantation increased CC tumor growth and stimulated angiogenesis. Cyclopamine attenuated tumor growth in the CX group, but not in the HuCCT-1 mono-implant (SX) group. Cyclopamine treatment decreased CC cell proliferation, suppressed microvessel density, and increased tumor necrosis in the CX group, but not in the SX group. Conclusion: Hepatic stellate cells stimulate the proliferation, migration, and invasion of CC cells, promote angiogenesis through HH signaling activation, and render CC more susceptible to necrosis by HH inhibitor. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
15. Neuroprotective profile of pyruvate against ethanol-induced neurodegeneration in developing mice brain.
- Author
-
Ullah, Najeeb, Naseer, Muhammad Imran, Ullah, Ikram, Kim, Tae Hyun, Lee, Hae Young, and Kim, Myeong Ok
- Subjects
NEUROPROTECTIVE agents ,NEURODEGENERATION ,PYRUVATES ,ETHANOL ,NEURAL development ,APOPTOSIS ,ALCOHOLISM ,PHYSIOLOGY - Abstract
Exposure to ethanol during developmental stages leads to several types of neurological disorders. Apoptotic neurodegeneration due to ethanol exposure is a main feature in alcoholism. Exposure of developing animals to alcohol induces apoptotic neuronal death and causes fetal alcohol syndrome. In the present study, we observed the possible protective effect of pyruvate against ethanol-induced neurodegeneration. Exposure of developing mice to ethanol (2.5 g/kg) induces apoptotic neurodegeneration and widespread neuronal cell death in the cortex and thalamus. Co-treatment of pyruvate (500 mg/kg) protects neuronal cell against ethanol by the reduced expression of caspase-3 in these brain regions. Immunohistochemical analysis and TUNNEL at 24 h showed that apoptotic cell death induced by ethanol in the cortex and thalamus is reduced by pyruvate. Histomorphological analysis at 24 h with cresyl violet staining also proved that pyruvate reduced the number of neuronal cell loss in the cortex and thalamus. The results showed that ethanol increased the expression of caspase-3 and thus induced apoptotic neurodegeneration in the developing mice cortex and thalamus, while co-treatment of pyruvate inhibits the induction of caspase-3 and reduced the cell death in these brain regions. These findings, therefore, showed that treatment of pyruvate inhibits ethanol-induced neuronal cell loss in the postnatal seven (P7) developing mice brain and may appear as a safe neuroprotectant for treating neurodegenerative disorders in newborns and infants. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
16. Decreased GABABR expression and increased neuronal cell death in developing rat brain after PTZ-induced seizure.
- Author
-
Naseer, Muhammad Imran, Ullah, Ikram, Al-Qahtani, Mohammed H, Karim, Sajjad, Ullah, Najeeb, Ansari, Shakeel Ahmed, Kim, Myeong Ok, and Bibi, Fehmida
- Abstract
The objective of this study was to evaluate the PTZ-induced seizures effects on GABAB receptor (R) expression and to observe its neurodegenerative effect in hippocampal part of developing rat brain. In the present study, high dose of pentylenetetrazol (PTZ 40 mg/kg) was injected in developing rats of age 5 weeks having average weight of 60-65 g for 4 days. Further, baclofen (B 3 mg/kg i.p) agonist and phaclofen (P 30 μg/rat) antagonist of GABABR were injected along with PTZ. Western blot analysis was used to elucidate expression of GABABR protein upon PTZ, baclofen and phaclofen exposure in the developing rat brain. Furthermore, PTZ-induced apoptotic neurodegeneration was also observed through the release of caspase-3 antibody and propidium iodide (PI) staining using confocal microscopy. Seizure was confirmed using electroencephalography (EEG) data obtained from the Laxtha EEG-monitoring device in the EEG recording room and EEG was monitored 5-15 min after PTZ injection. The results of the present study showed that PTZ-induced seizure significantly decreased GABABR expression and induced neuronal apoptosis in cortical and hippocampal part of brain. While, baclofen reverse the effect of PTZ by increasing the expression of GABABR as compared to the PTZ- , PTZ plus B- and PTZ plus P-treated groups. Our findings indicated that PTZ-induced seizure showed not only decrease in GABABR expression but also cause neuronal apoptosis in the developing rat brain. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
17. A novel kit for early diagnosis of Alzheimer's disease using a fluorescent nanoparticle imaging.
- Author
-
Park, Jun Sung, Kim, Sang Tae, Kim, Sang Yun, Jo, Min Gi, Choi, Myeong Jun, and Kim, Myeong Ok
- Subjects
ALZHEIMER'S disease diagnosis ,MICRORNA ,TAU proteins ,INTERLEUKIN-13 ,NANOMEDICINE - Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease and chronic illness with long preclinical phases and a long clinical duration. Until recently, a lack of potential therapeutic agents against AD was the primary focus of research, which resulted in less effort directed towards developing useful diagnostic approaches. In this study, we developed a WO2002/088706 kit that is composed of fluorescent nanoparticles for the early detection of AD. We provided a fluorescent nanoparticle for detecting markers and a kit for the early diagnosis of AD. The kit consists of a probe molecule comprising an oligonucleotide capable of detecting one or more AD-specific microRNAs (miRNAs) and biomarkers related to AD. Through screening, we selected miR-106b, miR-146b, miR-181a, miR-200a, miR-34a, miR-124b, miR-153, miR-155, Aβ
1-42 monomer (mAβ), Aβ1–42 oligomer (oAβ), UCHL1, NLRP3, Tau, STAT3, SORL1, Clusterin, APOE3, APOE4, Nogo-A, IL-13, and Visfatin to serve as AD- and inflammation-related markers. For detection of kit-binding properties, we checked the expression levels of amyloid beta (Aβ), tau protein, and inflammatory mediators in APP/PS/ApoE knockdown (KD) mice and a control group using co-localisation analysis conducted with a confocal microscope. Using a similar approach, we checked the expression levels of miRNAs in HT22 cells. Finally, we used the plasma from AD patients to confirm that our fluorescent nanoparticles and the WO2002/088706 kit will provide a possible early diagnosis to serve as an AD detector that can be further improved for future studies on targeting AD. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
18. Vanillic acid attenuates Aβ1-42-induced oxidative stress and cognitive impairment in mice.
- Author
-
Amin, Faiz Ul, Shah, Shahid Ali, and Kim, Myeong Ok
- Abstract
Increasing evidence demonstrates that β-amyloid (Aβ) elicits oxidative stress, which contributes to the pathogenesis and disease progression of Alzheimer's disease (AD). The aims of the present study were to determine and explore the antioxidant nature and potential mechanism of vanillic acid (VA) in Aβ
1-42 -induced oxidative stress and neuroinflammation mediated cognitive impairment in mice. An intracerebroventricular (i.c.v.) injection of Aβ1-42 into the mouse brain triggered increased reactive oxygen species (ROS) levels, neuroinflammation, synaptic deficits, memory impairment, and neurodegeneration. In contrast, the i.p. (intraperitoneal) administration of VA (30 mg/kg, for 3 weeks) after Aβ1-42 -injection enhanced glutathione levels (GSH) and abrogated ROS generation accompanied by an induction of the endogenous nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) via the activation of Akt and glycogen synthase kinase 3β (GSK-3β) in the brain mice. Additionally, VA treatment decreased Aβ1-42 -induced neuronal apoptosis and neuroinflammation and improved synaptic and cognitive deficits. Moreover, VA was nontoxic to HT22 cells and increased cell viability after Aβ1-42 exposure. To our knowledge, this study is the first to reveal the neuroprotective effect of VA against Aβ1-42 -induced neurotoxicity. Our findings demonstrate that VA could potentially serve as a novel, promising, and accessible neuroprotective agent against progressive neurodegenerative diseases such as AD. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
19. Osmotin attenuates LPS-induced neuroinflammation and memory impairments via the TLR4/NFκB signaling pathway.
- Author
-
Badshah, Haroon, Ali, Tahir, and Kim, Myeong Ok
- Published
- 2016
- Full Text
- View/download PDF
20. Osmotin attenuates amyloid beta-induced memory impairment, tau phosphorylation and neurodegeneration in the mouse hippocampus.
- Author
-
Ali, Tahir, Yoon, Gwang Ho, Shah, Shahid Ali, Lee, Hae Young, and Kim, Myeong Ok
- Subjects
AMYLOID beta-protein ,PHOSPHORYLATION ,NEURODEGENERATION ,ALZHEIMER'S disease ,PLANT proteins ,IMMUNOHISTOCHEMISTRY ,NEUROTOXICOLOGY ,LABORATORY mice - Abstract
The pathological hallmarks of Alzheimer's disease (AD) include amyloid beta (Aβ) accumulation, neurofibrillary tangle formation, synaptic dysfunction and neuronal loss. In this study, we investigated the neuroprotection of novel osmotin, a plant protein extracted from Nicotiana tabacum that has been considered to be a homolog of mammalian adiponectin. Here, we observed that treatment with osmotin (15 μg/g, intraperitoneally, 4 hr) at 3 and 40 days post-intracerebroventricular injection of Aβ
1-42 significantly ameliorated Aβ1-42 -induced memory impairment in mice. These results revealed that osmotin reverses Aβ1-42 injection-induced synaptic deficits, Aβ accumulation and BACE-1 expression. Treatment with osmotin also alleviated the Aβ1-42 -induced hyperphosphorylation of the tau protein at serine 413 through the regulation of the aberrant phosphorylation of p-PI3K, p-Akt (serine 473) and p-GSK3β (serine 9). Moreover, our western blots and immunohistochemical results indicated that osmotin prevented Aβ1-42 -induced apoptosis and neurodegeneration in the Aβ1-42 -treated mice. Furthermore, osmotin attenuated Aβ1-42 -induced neurotoxicity in vitro.To our knowledge, this study is the first to investigate the neuroprotective effect of a novel osmotin against Aβ1-42 -induced neurotoxicity. Our results demonstrated that this ubiquitous plant protein could potentially serve as a novel, promising, and accessible neuroprotective agent against progressive neurodegenerative diseases such as AD. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.