• Reproductive and Developmental Biology
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• 제33권1호
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• pp.49-54
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• 2009

The current study was designed to evaluate the effects of the reactive oxygen species (ROS) generated with a xanthine (X) and xanthine oxidase system (XO) on sperm function and DNA fragmentation in porcine spermatozoa. ROS were produced by a combination of $1,000{\mu}M$ X and 50 mU/ml XO. The ROS scavengers such as superoxide dismutase (SOD) (200 U/ml) and catalase (CAT) (500 U/ml) were also tested. Spermatozoa were incubated for 2 hours in BWW medium with a combination of X-XO supplemented with or without antioxidants at $37^{\circ}C$ under 5% $CO_2$ incubator. Ca-ionophore-induced acrosome reaction, the proportion of swollen spermatozoa under hypo-osmotic condition, malondialdehyde formation for the analysis of lipid peroxidation, and the proportion of DNA fragmentation were determined after 2 hours incubation. The action of ROS on porcine spermatozoa resulted in decreased Ca-ionophore-induced acrosome reaction and membrane integrity, increased the formation of malondialdehyde, and the proportion of sperm with DNA fragmentation(p<0.05). The toxic effects caused by ROS were completely alleviated by CAT in terms of sperm function and characteristics, however SOD did not serve the same scavenger effect as CAT. To conclude, the ROS can cause significant damage to porcine sperm functions and characteristics, which can be minimized by the use of antioxidants.

• Molecules and Cells
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• 제37권12호
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• pp.907-911
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• 2014

The function of reactive oxygen species (ROS) as second messengers in cell differentiation has been demonstrated only for a limited number of cell types. Here, we used a well-established protocol for BMP2-induced neuronal differentiation of neural crest stem cells (NCSCs) to examine the function of BMP2-induced ROS during the process. We first show that BMP2 indeed induces ROS generation in NCSCs and that blocking ROS generation by pretreatment of cells with diphenyleneiodonium (DPI) as NADPH oxidase (Nox) inhibitor inhibits neuronal differentiation. Among the ROS-generating Nox isozymes, only Nox4 was expressed at a detectable level in NCSCs. Nox4 appears to be critical for survival of NCSCs at least in vitro as down-regulation by RNA interference led to apoptotic response from NCSCs. Interestingly, development of neural crest-derived peripheral neural structures in Nox4-/- mouse appears to be grossly normal, although Nox4-/- embryos were born at a sub-Mendelian ratio and showed delayed over-all development. Specifically, cranial and dorsal root ganglia, derived from NCSCs, were clearly present in Nox4-/- embryo at embryonic days (E) 9.5 and 10.5. These results suggest that Nox4-mediated ROS generation likely plays important role in fate determination and differentiation of NCSCs, but other Nox isozymes play redundant function during embryogenesis.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2000년도 제39차 춘계 학술대회
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• pp.37-42
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• 2000

Objective: To determine whether particular semen characteristics in various clinical diagnoses of infertility are associated with high oxidative stress and whether any group of infertile men is more likely to have high seminal oxidative stress. Reactive oxygen species (ROS) play an important role in sperm physiological functions, but elevated levels of ROS or oxidative stress are related to male infertility. Design: Measurement of sperm concentration, motility, morphology, seminal ROS, and total antioxidant capacity (TAC) in patients seeking infertility treatment and controls. Setting: Male infertility clinic of a tertiary care center. Patient(s): One hundred sixty-seven infertile patients and 19 controls. Intervention(s): None. Main Outcome Measure(s): Semen characteristics, seminal ROS, and TAC in samples from patients with various clinical diagnoses and controls. Result(s): Fifteen patients (9.0%) were Endtz positive and 152(91.0%) Endtz negative. Sperm concentration, motility, and morphology were significantly reduced in all groups compared with the controls (P = .02), except in varicocele associated With infection group. Mean (${\pm}$SD) ROS levels in patient groups ranged from 2.2 ${\pm}$ 0.13 to 3.2 ${\pm}$ 0.35, signilicantly higher than controls (1.3 ${\pm}$ 0.3; P<.005). Patient groups had a significantly lower mean (${\pm}$SD) TAC from 1014.75 ${\pm}$ 79.22 to 1173.05 ${\pm}$ 58.07 than controls (1653 ${\pm}$ 115.28, P<.001), except ill the vaseclony reversal group (1532.02 ${\pm}$ 74.24). Sperm concentration was negatively correlated with ROS both overall and within all groups (P${\leq}$.007), with the exception of idiopathic infertility. Conclusion(s): Irrespective of the clinical diagnosis and semen characteristics, the presence of seminal oxidative stress in infertile men suggests its role in the pathophysiology of infertility. Medical or surgical treatments for infertility in these men should include strategies to reduce oxidative stress.

• Environmental Analysis Health and Toxicology
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• 제20권1호
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• pp.75-85
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• 2005

This study was aimed to know the effect of cadmium chloride (CdCl₂) on glucose transport in L6 myotube and its action mechanism. CdCl₂ increased the 2-deoxy- (l-3H)-D-glucose (2-DOG) uptake 1.9 and 2.4 fold at 10 and 25 μM respectively. To investigate the stimulating-mechanism of glucose transport induced by CdCl₂, the wortmannin and PD98059 were used as PI3K (phosphatidylinositol 3-kinase) inhibitor and MAPK inhibitor respectively, which did not affect 2-DOG uptake. This fact suggests that CdCl₂ induced 2-DOG uptake may not be concerned to the insulin signalling pathway. Whereas nifedipine, a calcium channel blocker, and trifluoperazine, a calmodulin inhibitor, were found to inhibit the 2-DOG uptake stimulted by CdCl₂. In addition, we also measured the ROS (reactive oxygen species) production and GSH level in L6 myotube to investigate the correlation between the glucose uptake and ROS. CdCl₂(25 μM) increased ROS generation approximately 1.5 fold and changed the cellular GSH level, but GSSG/GSH ratio remained unchanged. CdCl₂ stimulated 2-DOG uptake and ROS generation were inhibited by N-acetylcystein. And BSO pretreatment, a potent inhibitor of γ-GCS, resulted in the dramatic decrease of 2-DOG uptake and also the increase of the sensitivity to cadmium cytotoxicity. The obtained results suggest that CdCl₂-stimulated glucose uptake might be based on the activation of HMP shunt as an antioxidant defense mechanism of the cells.

• Fisheries and Aquatic Sciences
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• 제26권1호
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• pp.24-34
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• 2023

Reactive oxygen species (ROS) at high concentrations induce oxidative stress, an imbalanced redox state that is a prevalent cause of neurodegenerative disorders. This study aimed to investigate the protective effect of Capsosiphon fulvescens (CF) extract on oxidative stress-induced impairment of cognitive function in models of neurodegenerative diseases. CF was extracted with subcritical water and several solvents and H₂O₂ (0.25 mM) or aluminum chloride (AlCl₃; 25 µM) as an inducer of ROS was treated in PC12 neuronal cells and zebrafish larvae. All statistical analyses were performed using one-way analysis of variance and Dunnett's test using GraphPad Prism. H₂O₂ and AlCl₃ were found to significantly induce ROS production in PC12 neuronal cells and zebrafish larvae. In addition, they strongly affected intracellular Ca²⁺ levels, antioxidant enzyme activity, brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) signaling, acetylcholinesterase (AChE) activity, and hallmarks of Alzheimer's disease. However, treatment of H₂O₂-induced PC12 cells or AlCl₃-induced zebrafish larvae with CF subcritical water extract at 90℃ and CF water extract effectively regulated excessive ROS production, intracellular Ca²⁺ levels, and mRNA expression of superoxide dismutase, glutathione peroxide, glycogen synthase kinase-3 beta, β-amyloid, tau, AChE, BDNF, and TrkB. Our study suggested that CF extracts can be a potential source of nutraceuticals that can improve the impairment of cognitive function and synaptic plasticity by regulating ROS generation in neurodegenerative diseases.

• Parasites, Hosts and Diseases
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• 제62권3호
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• pp.270-280
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• 2024

Trichomoniasis is caused by a sexually transmitted flagellate protozoan parasite Trichomonas vaginalis. T. vaginalis-derived secretory products (TvSP) contain lipid mediators such as leukotriene B₄ (LTB₄) and various cysteinyl leukotrienes (CysLTs) which included LTC₄, LTD₄, and LTE₄. However, the signaling mechanisms by which T. vaginalis-induced CysLTs stimulate interleukin (IL)-8 production in human mast cells remain unclear. In this study, we investigated these mechanisms in human mast cells (HMC-1). Stimulation with TvSP resulted in increased intracellular reactive oxygen species (ROS) generation and NADPH oxidase 2 (NOX2) activation compared to unstimulated cells. Pre-treatment with NOX2 inhibitors such as diphenyleneiodonium chloride (DPI) or apocynin significantly reduced ROS production in TvSP-stimulated HMC-1 cells. Additionally, TvSP stimulation increased NOX2 protein expression and the translocation of p47^phox from the cytosol to the membrane. Pretreatment of HMC-1 cells with PI3K or PKC inhibitors reduced TvSP-induced p47^phox translocation and ROS generation. Furthermore, NOX2 inhibitors or NOX2 siRNA prevented CREB phosphorylation and IL-8 gene expression or protein secretion induced by TvSP. Pretreatment with a CysLTR antagonist significantly inhibited TvSP-induced ROS production, CREB phosphorylation, and IL-8 production. These results indicate that CysLT-mediated activation of NOX2 plays a crucial role in ROS-dependent IL-8 production in human mast cells stimulated by T. vaginalis-secreted CysLTs. These findings enhance our understanding of the inflammatory response in trichomoniasis and may inform the development of targeted therapies to mitigate this response.

• 생명과학회지
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• 제25권9호
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• pp.984-992
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• 2015

혈근초(Sanguinaria canadensis)에서 처음 분리된 sanguinarine은 항산화, 항암 및 면역 증강 등의 효능이 있는 것으로 알려진 alkaloid 계열 물질 중의 하나이다. 본 연구에서는 인체간암 HepG2 세포를 대상으로 sanguinarine의 apoptosis 유도 효능 및 관련 기전 해석을 시도하였다. 본 연구의 결과에 의하면 sanguinarine은 HepG2 간암세포의 증식을 처리 농도 의존적으로 억제하였으며, 이는 apoptosis 유도와 연관성이 있었다. Sanguinarine에 의한 apoptosis 유도에는 Fas 및 Bax의 발현 증가, 미토콘드리아에서 세포질로의 cytochrome c 유리 및 MMPl (Δψm)의 소실을 동반하였다. Sanguinarine은 intrinsic 및 extrinsic apoptosis pathway의 활성에 관여하는 initiator caspase인 caspase-9와 -8의 활성과 effector caspase인 caspase-3의 활성 및 PARP 단백질의 단편화를 유발하였다. Sanguinarine은 또한 ROS의 생성을 촉진시켰으며, N-acetylcysteine 처리에 의한 ROS의 생성을 차단하였을 경우, sanguinarine에 의한 apoptosis 효능이 완벽하게 차단되었다. 아울러 sanguinarine은 Akt의 인산화를 억제한 반면, MAPKs의 인산화를 촉진시켰으며, 특히 PI3K와 ERK의 선택적 억제제는 sanguinarine에 의한 HepG2 간암세포의 증식을 더욱 억제시켰다. 따라서 sanguinarine에 의한 HepG2 간암세포의 apoptosis 유발에는 ROS 생성 의존적인 intrinsic 및 extrinsic signaling pathway가 동시에 활성화되며, PI3K/Akt 및 ERK 신호계가 관여함을 알 수 있었다.

• Biomolecules & Therapeutics
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• 제26권5호
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• pp.503-511
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• 2018

Triclosan (TCS) and bisphenol A (BPA) are endocrine-disrupting chemicals that interfere with the hormone or endocrine system and may cause cancer. Kaempferol (Kaem) and 3,3'-diindolylmethane (DIM) are phytoestrogens that play chemopreventive roles in the inhibition of carcinogenesis and cancer progression. In this study, the influence of TCS, BPA, Kaem, and DIM on proliferation and apoptotic abilities of VM7Luc4E2 breast cancer cells were examined. MTT assay revealed that TCS ($0.1-10{\mu}M$), BPA ($0.1-10{\mu}M$) and E2 ($0.01-0.0001{\mu}M$) induced significant cell proliferation of VM7Luc4E2 cells, which was restored to the control (0.1% DMSO) by co-treatment with Kaem ($30{\mu}M$) or DIM ($15{\mu}M$). Reactive oxygen species (ROS) production assays showed that TCS and BPA inhibited ROS production of VM7Luc4E2 cells similar to E2, but that co-treatment with Kaem or DIM on VM7Luc4E2 cells induced increased ROS production. Based on these results, the effects of TCS, BPA, Kaem, and DIM on protein expression of apoptosis and ROS production-related markers such as Bax and Bcl-xl, as well as endoplasmic reticulum (ER) stress-related markers such as $eIF2{\alpha}$ and CHOP were investigated by Western blot assay. The results revealed that TCS, and BPA induced anti-apoptosis by reducing ROS production and ER stress. However, Kaem and DIM effectively inhibited TCS and BPA-induced anti-apoptotic processes in VM7Luc4E2 cells. Overall, TCS and BPA were revealed to be distinct xenoestrogens that enhanced proliferation and anti-apoptosis, while Kaem and DIM were identified as natural chemopreventive compounds that effectively inhibited breast cancer cell proliferation and increased anti-apoptosis induced by TCS and BPA.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.144.2-145
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• 2003

Reactive Oxygen Species (ROS) are produced during normal cellular function. ROS are very transient species due to their high chemical reactivity that leads to lipid peroxidation and oxidation of some enzyme, massive protein oxidation and degradation. Under normal conditions, antioxidant are substances that either directly or indirectly protect cells against adverse effects of ROS. Several biologically important compounds have been reported to have antioxidant functions. These incluce vitamin C, vitamin E, GSH, flavonoids. superoxidee dismutase(SOD), glutathione peroxidase(GPX) and catalase(CAT). (omitted)

• Toxicological Research
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• 제33권3호
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• pp.219-224
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• 2017

Lipin1 was identified as a phosphatidate phosphatase enzyme, and it plays a key role in lipid metabolism. Since free radicals contribute to metabolic diseases in the liver, this study investigated the effects of free radicals on the regulation of Lipin1 expression in Huh7 and AML12 cells. Hydrogen peroxide induced mRNA and protein expression of Lipin1 in Huh7 cells, which was assayed by quantitative RT-PCR and immunoblotting, respectively. Induction of Lipin1 by hydrogen peroxide was confirmed in AML12 cells. Hydrogen peroxide treatment significantly increased expression of sterol regulatory element-binding protein (SREBP)-2, but not SREBP-1. Moreover, nuclear translocation of SREBP-2 was detected after hydrogen peroxide treatment. Hydrogen peroxide-induced Lipin1 or SREBP-2 expression was significantly reduced by N-acetyl-$\small{L}$-cysteine treatment, indicating that reactive oxygen species (ROS) were implicated in Lipin1 expression. Next, we investigated whether the hypoxic environments that cause endogenous ROS production in mitochondria in metabolic diseases affect the expression of Lipin1. Exposure to hypoxia also increased Lipin1 expression. In contrast, pretreatment with antioxidants attenuated hypoxia-induced Lipin1 expression. Collectively, our results show that ROS activate SREBP-2, which induces Lipin1 expression.