Roles for the Lipid-signaling enzyme MitoPLD in mitochondrial dynamics, piRNA biogenesis, and spermatogenesis

( Qun Gao ),( Michael A. Frohman ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.1

Phospholipase D (PLD), a superfamily of signaling enzymes that most commonly generate the lipid second messenger Phosphatidic Acid (PA), is found in diverse organisms from bacteria to man and functions in multiple cellular pathways. A fascinating member of the family, MitoPLD, is anchored to the mitochondrial surface and has two reported roles. In the first role, MitoPLD-generated PA regulates mitochondrial shape through facilitating mitochondrial fusion. In the second role, MitoPLD performs a critical function in a pathway that creates a specialized form of RNAi required by developing spermatocytes to suppress transposon mobilization during meiosis. This spermatocyte-specific RNAi, known as piRNA, is generated in the nuage, an electron-dense accumulation of RNA templates and processing proteins that localize adjacent to mitochondria in a structure also called intermitochondrial cement. In this review, we summarize recent findings on these roles for MitoPLD functions, highlighting directions that need to be pursued to define the underlying mechanisms. (BMB reports 2012; 45(1): 7-13)

Combined water flux enhancement of PES-based TFC membranes in ultrasonic-assisted forward osmosis processes

Qun Wang,Xueli Gao,Zhun Ma,Jian Wang,Xiaojuan Wang,Yang Yang,Congjie Gao 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.64 No.-

For PES-based TFC FO membranes, a significant water flux surge occurred after a moderate ultrasonic irradiation. The Change in membrane transport parameters illustrated that internal concentration polarization (ICP) was weakened due to decreased structural parameter. Combined water flux enhancement via real-time ultrasonic irradiation was obtained and related to the CP effect and membrane orientation. Increasing irradiation intensity was more suitable in PRO mode than in FO mode. Low FS concentration in concentration combinations represented high ratio of ultrasonic-induced flux increment to energy input. Multiplying concentration difference was beneficial to obtain high conversion ratio of ultrasonic power to water flux.

Punicic Acid from Trichosanthes kirilowii Seed Oil Is Rapidly Metabolized to Conjugated Linoleic Acid in Rats

Gao-Feng Yuan,Jing-Qun Yuan,Duo Li 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.2

The incorporation and metabolism of orally administered punicic acid (PA), one isomer of conjugated linolenic acid (CLNA), in rat tissues and plasma were studied over a 24-hour period. The punic acid was derived from Trichosanthes kirilowii Maxim seed oil, a unique PA-containing material, and identified and analyzed by high-performance liquid chromatography and gas chromatography-mass spectrometry. The results show that PA was incorporated and metabolized to 9c,11t-conjugated linoleic acid (CLA) in rat plasma, liver, kidney, heart, brain, and adipose tissue. The level of PA and CLA in liver and plasma was higher than in brain, heart, kidney, and adipose tissue, and the lowest accumulation occurred in the brain. The observation that PA can be converted into 9c,11t-CLA has gained increased importance since it has been demonstrated that 9c,11t-CLA exerts many biological activities. Therefore natural resources containing CLNA, especially edible T. kirilowii seed, could be a potential dietary source of CLA, following PA metabolism. PA is expected to be used as a functional food and nutraceutical.

Prenylated indole diketopiperazine alkaloids from a mangrove rhizosphere soil derived fungus Aspergillus effuses H1-1

Huquan Gao,Tian-Jiao Zhu,De-Hai Li,Qian Qun Gu,Weizhong Liu 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.8

One new prenylated indole diketopiperazinealkaloid, named dihydroneochinulin B (1), one known spiropolyketide-diketopiperazine hybrid cryptoechinuline D (2)and three related known metabolites didehydroechinulin B(3), neoechinulin B (4) and auroglaucin (5) were isolatedfrom the mangrove rhizosphere soil derived fungus, Aspergilluseffuses H1-1. The structures were assigned by detailedspectroscopic analysis. The enantiomers of cryptoechinulineD (2) were separated to be (?)-cryptoechinuline D (2a) and(-)-cryptoechinuline D (2b) by chiral HPLC, and theirabsolute configurations were determined by ECD analysis. The cytotoxic effects of the compounds were preliminarilyevaluated on P388, HL-60, BEL-7402 and A-549 cell linesby SRB or MTT methods, and compounds 2, 2a and 3showed significant activities.

CK2 phosphorylates AP-2α and increases its transcriptional activity

( Kai Qun Ren ),( Shuang Lin Xiang ),( Fang Li He ),( Wen Feng Zhang ),( Xiao Feng Ding ),( Yan Yang Wu ),( Li Ping Yang ),( Jian Lin Zhou ),( Xiang Gao ),( Jian Zhang ) 생화학분자생물학회(구 한국생화학분자생물학회) 2011 BMB Reports Vol.44 No.7

Transcription factor AP-2α involves in the process of mammalian embryonic development and tumorigenesis. Many studies have shown that AP-2α functions in association with other interacting proteins. In a two-hybrid screening, the regulatory subunit β of protein casein kinase 2 (CK2β) was identified as an interacting protein of AP-2α; we confirmed this interaction using in-vitro GST pull-down and in-vivo co-immunoprecipitation assays; in an endogenous co-immunoprecipitation experiment, we further found the catalytic subunit α of protein casein kinase 2 (CK2α) also exists in the complex. Phosphorylation analysis revealed that AP-2α was phosphorylated by CK2 kinase majorly at the site of Ser429, and such phosphorylation could be blocked by CK2 specific inhibitor 4,5,6,7-tetrabromobenzotriazole (TBB) in a dose-dependent manner. Luciferase assays demonstrated that both CK2α and CK2β enhanced the transcription activity of AP-2α; moreover, CK2β increased the stability of AP-2α. Our data suggest a novel cellular function of CK-2 as a transcriptional co-activator of AP-2α.

ACTIVE LQR MULTI-AXLE-STEERING METHOD FOR IMPROVING MANEUVERABILITY AND STABILITY OF MULTI-TRAILER ARTICULATED HEAVY VEHICLES

You-Qun Zhao,Zhao Wen Deng,Qi Xian Zhao,Bao Hua Wang,Wei Gao,Xin Xin Kong 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.4

Directional performance and highway stability are two important aspects that need to be considered in development and design of a heavy articulated vehicles. To improve the maneuverability and stability of a multi-trailer articulated heavy vehicle (MTAHV), an active linear quadratic regulator (LQR) multi-axle-steering method is designed and examined. First, a linear yaw-plane model with four-degree-of freedom (4-DOF) for MTAHV is built and validated. Thus, a reference model supplying the desired state responses is introduced. Then, an active control algorithm of multi-axle-steering for the rear axles of tractor and full-trailer is investigated, and a LQR controller is proposed based on the linear vehicle model to make the control variables track the desired state responses. The control strategy concentrates on keeping the actual yaw rate and side-slip angle follow the steady-state yaw rate and zero side-slip angle. Finally, the effectiveness of the designed approach on enhancing the maneuverability and stability of the MTAHV have been validated through the simulations of the low-speed 360o roundabout and the single lane-change maneuver with high speed, respectively. The method has a certain reference value for improving the active safety of the MTAHV.

Nitric oxide-caused rabbit chondrocyte apoptosis is linked to cytoskeletal protein proteolysis anomaly through intracellular JNK and ERK signal pathways

Chen Qun,Kao Xibin,Gao Yan,Chen Jinghong,Dong Zhaoheng,Chen Chen 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.1

Backgrounds Nitric oxide (NO) plays a key role in the pathological chondrocyte apoptosis of osteoarthritis (OA). Cytoskeletal proteins form cytoskeleton network to maintain normal chondrocyte structure and function. JNK and ERK pathways are the signal pathways involved in the cell apoptosis. The role of cytoskeletal proteins in cytoskeleton perturbation and cell apoptosis was investigated in this study. Objectives In vitro cell apoptosis was induced in rabbit articular chondrocytes by NO donor Sodium Nitroprusside (SNP). The JNK-specific inhibitor SP600125 and ERK-specific inhibitor PD98059 were employed to clarify the mechanism. The level of apoptosis was evaluated by TUNEL assay and Annexin V flow cytometry. Results SNP induced concentration-dependent apoptosis, which was further enhanced by PD98059 but reduced by SP600125. Furthermore, PD98059 significantly increased caspase-3 expression and activity respectively, whereas SP600125 reduced caspase- 3 expression and activity. SP600125 increased the cytoskeletal protein mRNA and protein expression, while PD98059 decreased them. Conclusion Intracellular JNK/ERK pathways were involved in chondrocyte apoptosis induced by SNP through oppositely regulated effects on cytoskeletal proteins; ERK pathway protected cytoskeletal protein from dissolution via inhibition of caspase-3 activation, while JNK pathway promoted the dissolution via activation of caspase-3 activity.

Punicic Acid from Trichosanthes kirilowii Seed Oil Is Rapidly Metabolized to Conjugated Linoleic Acid in Rats

Yuan, Gao-Feng,Yuan, Jing-Qun,Li, Duo The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.2

The incorporation and metabolism of orally administered punicic acid (PA), one isomer of conjugated linolenic acid (CLNA), in rat tissues and plasma were studied over a 24-hour period. The punic acid was derived from Trichosanthes kirilowii Maxim seed oil, a unique PA-containing material, and identified and analyzed by high-performance liquid chromatography and gas chromatography-mass spectrometry. The results show that PA was incorporated and metabolized to 9c,11t-conjugated linoleic acid (CLA) in rat plasma, liver, kidney, heart, brain, and adipose tissue. The level of PA and CLA in liver and plasma was higher than in brain, heart, kidney, and adipose tissue, and the lowest accumulation occurred in the brain. The observation that PA can be converted into 9c,11t-CLA has gained increased importance since it has been demonstrated that 9c,11t-CLA exerts many biological activities. Therefore natural resources containing CLNA, especially edible T. kirilowii seed, could be a potential dietary source of CLA, following PA metabolism. PA is expected to be used as a functional food and nutraceutical.

Protective Effect of Astragalus polysaccharides on Liver Injury Induced by Several Different Chemotherapeutics in Mice

Liu, Wen,Gao, Fang-Fang,Li, Qun,Lv, Jia-Wei,Wang, Ying,Hu, Peng-Chao,Xiang, Qing-Ming,Wei, Lei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Side effects are an unavoidable consequence of chemotherapy drugs, during which liver injury often takes place. The current study was designed to investigate the protective effect of Astragalus polysaccharides (APS) against the hepatotoxicity induced by frequently-used chemical therapy agents, cyclophosphamide (CTX), docetaxel (DTX) and epirubicin (EPI)) in mice. Mice were divided into five groups, controls, low or high dose groups ($DTX_L$, $CTX_L$, $EPI_L$ or $DTX_H$, $CTX_H$, $EPI_H$), and low or high dose chemotherapeutics+APS groups ($DTX_L$+APS, $CTX_L$+APS, $EPI_L$+APS or $DTX_H$+APS, $CTX_H$+APS, $EPI_H$+APS). Controls were treated with equivalent normal saline for 28 days every other day; low or high dose group were intraperitoneal (i.p) injected with low or high doses of CTX, DTX and EPI for 28 days every other day; low or high dose chemotherapeutics+APS group were separately intraperitoneal (i.p) injected with chemotherapeutics for 28 days every other day and i.p with APS (100 mg/kg) for 7 days continually from the 22th to the 28th days. The body weight, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), histopathological features, and ultrastructure morphological change of liver tissues, protein expression level of caspase-3 were estimated at different time points. With high dose treatment of DTX, CTX and EPI, weight gain was inhibited and serum levels of ALT and AST were significantly increased. Sections of liver tissue showed massive hepatotoxicity in $CTX_H$ group compared to the control group, including hepatic lobule disorder, granular and vacuolar degeneration and necrosis in hepatic cells. These changes were confirmed at ultrastructural level, including obvious pyknosis, heterochromatin aggregation, nuclear membrane resolution, and chondrosome crystal decrease. Western blotting revealed that the protein levels of caspase-3 increased in $CTX_H$ group. The low dose groups exhibited trivial hepatotoxicity. More interestingly, after 100 mg/kg APS, liver injury was redecued not only regarding serum transaminase activities (low or high dose chemotherapeutics+APS group), but also from pathological and ultrastructural changes and the protein levels of caspase-3 ($CTX_H$+APS group). In conclusion, DTX, CTX and EPI induce liver damage in a dose dependent manner, whereas APS exerted protective effects.

Methylation Status of Transcriptional Modulatory Genes Associated with Colorectal Cancer in Northeast China

Han-Lu Gao,Xuan Wang,Hong-Ru Sun,Jun-De Zhou,Shang-Qun Lin,Yu-Hang Xing,Lin Zhu,Hai-Bo Zhou,Ya-Shuang Zhao,Qiang Chi,Yu-Peng Liu 거트앤리버 소화기연관학회협의회 2018 Gut and Liver Vol.12 No.2

Background/Aims: Methylation status plays a causal role in carcinogenesis in targeted tissues. However, the relationship between the DNA methylation status of multiple genes in blood leukocytes and colorectal cancer (CRC) susceptibility as well as interactions between dietary factors and CRC risks are unclear. Methods: We performed a case-control study with 466 CRC patients and 507 cancer-free controls to investigate the association among the methylation status of individual genes, multiple CpG site methylation (MCSM), multiple CpG site heterogeneous methylation and CRC susceptibility. Peripheral blood DNA methylation levels were detected by performing methylation-sensitive high-resolution melting. Results: Total heterogeneous methylation of CA10 and WT1 conferred a significantly higher risk of CRC (adjusted odds ratio [ORadjusted], 5.445; 95% confidence interval [CI], 3.075 to 9.643; ORadjusted, 1.831; 95% CI, 1.100 to 3.047; respectively). Subjects with high-level MCSM (MCSM-H) status demonstrated a higher risk of CRC (ORadjusted, 4.318; 95% CI, 1.529 to 12.197). Additionally, interactions between the high-level intake of fruit and CRH, WT1, and MCSM on CRC were statistically significant. Conclusions: The gene methylation status of blood leukocytes may be associated with CRC risk. MCSM-H of blood leukocytes was associated with CRC, especially in younger people. Some dietary factors may affect hypermethylation status and influence susceptibility to CRC.