Rationale: Gardeniae Fructus (GF, the dried ripe fruits of Gardenia jasminoides Ellis) has been popularly applied to traditional medicine to treat hepatic disorders and various diseases. So,we looked into the pharmacological effects and underlying mechanisms of Gardenia fructus (GF) against mice models with liver fibrosis caused by thioacetamide (TAA). Methods: The GF used in this experiment was supplied from Bonchowon. Dried GF (100 g) was extracted with water (1 L) for 2 h. The powder of GF was a yield of 24.6% and kept at −80 °C before use. The animal protocol was approved by the Ethics Committee of the Daegu Haany University and performed according to ‘the Guidelines for Animal Experiment’. C57BL/6 mice (male, 20–25 g). A total of thirty-six mice were divided into 4 groups (n = 9 for each group): Normal, Control (TAA only), GF (200 mg/kg), and Silymarin (50 mg/kg), respectively. Liver fibrosis was induced by TAA injection per week for 8 weeks. The treatment drugs for liver fibrosis both GF and Silymarin were administrated for 8 weeks 90 min prior to TAA injection. And we analyzed serum biochemistry, Immunohistochemistry (IHC) and Immunofluorescence (IF), proteins in liver. For validating possible mechanisms of GF on hepatic oxidation and fibrosis we cultured human blastoma cell line, HepG2, and hepatic stellate cells (HSCs) line, LX-2 cells, respectively. Results: GF reduced oxidation of hepatic tissue while also reducing inflammation in the liver. We further verified that GF caused ECM degradations, which alleviated liver fibrosis. We discovered the GF-regulated epigenetic regulator Sirtuin 1 (SIRT1) in the TAA-injected liver tissue, which provides insight into a potential underlying mechanism of GF. Through the modulation of its downstream proteins, including AMP-activated protein kinase (AMPK), p47phox, NADPH oxidase 2, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1, respectively, SIRT1-related signaling pathways provided strong support for these changes. We employed HepG2 cells with hydrogen peroxide treated oxidative stress and chronic exposure conditions to confirm the potential mechanism of GF through cellular SIRT1 degradation. Additionally, GF significantly reduced ECM accumulations in LX-2 cells that were generated by TGF-1 and relied on SIRT1. Conclusion: GF showed strong antioxidant effects by enhancement of endogenous an-otioxidant components in the liver tissue especially recoveries of SOD and GPx. GF could regulate Kupffer cell activation and their numbers by diminishing pro-inflammatory cytokines. GF strongly led to inactivate HSCs activation by evidence of amelioration of ECM resolutions and pro-fibrogenic cytokines during liver fibrosis. The corresponded mechanisms for the above properties of GF may regulate AMPK/SIRT1 signaling pathway in hepatocytes and HSCs, especially focusing on the beneficial effects of SIRT1 in both cell types. References: He, T.; Shen, H.; Zhu, J.; Zhu, Y.; He, Y.; Li, Z.; Lu, H. Geniposide attenuates cadmiuminduced oxidative stress injury via Nrf2 signaling in osteoblasts. Mol. Med. Rep. 2019, 20, 1499–1508. Gillessen, A.; Schmidt, H.H. Silymarin as Supportive Treatment in Liver Diseases: A Narrative Review. Adv. Ther. 2020, 37, 1279–1301. Hisahara, S.; Chiba, S.; Matsumoto, H.; Tanno, M.; Yagi, H.; Shimohama, S.; Sato, M.; Horio, Y. Histone deacetylase SIRT1 modulates neuronal differentiation by its nuclear translocation. Proc. Natl. Acad. Sci. USA 2008, 105, 15599–1560. Li, S.; Qian, Q.; Ying, N.; Lai, J.; Feng, L.; Zheng, S.; Jiang, F.; Song, Q.; Chai, H.; Dou, X. Activation of the AMPK-SIRT1 pathway contributes to protective effects of Salvianolic acid A against lipotoxicity in hepatocytes and NAFLD in mice. Front. Pharmacol. 2020, 11, 560905. Disclosure of Interest: S.-S. Roh Grant / Research Support from: This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No.2018R1A5A2025272), M.-R. Shin: None declared, J. A. Lee: None declared, M. Kim: None declared, J. Moon: None declared, J.-W. Nam: None declared, H. Choi: None declared, Y.-J. Mun: None declared, H.-J. Park: None declared

The endoplasmic reticulum (ER) and mitochondria form a unique subcellular compartment called mitochondria-associated ER membranes (MAMs). Disruption of MAMs impairs Ca2+ homeostasis, triggering pleiotropic effects in the neuronal system. Genome-wide kinase-MAM interactome screening identifies casein kinase 2 alpha 1 (CK2A1) as a regulator of composition and Ca2+ transport of MAMs. CK2A1-mediated phosphorylation of PACS2 at Ser207/208/213 facilitates MAM localization of the CK2A1-PACS2-PKD2 complex, regulating PKD2-dependent mitochondrial Ca2+ influx. We further reveal that mutations of PACS2 (E209K and E211K) associated with developmental and epileptic encephalopathy-66 (DEE66) impair MAM integrity through the disturbance of PACS2 phosphorylation at Ser207/208/213. This, in turn, causes the reduction of mitochondrial Ca2+ uptake and the dramatic increase of the cytosolic Ca2+ level, thereby, inducing neurotransmitter release at the axon boutons of glutamatergic neurons. In conclusion, our findings suggest a molecular mechanism that MAM alterations induced by pathological PACS2 mutations modulate Ca2+-dependent neurotransmitter release.

Carbon nanotube (CNT)-based composite or hybrid materials have been broadly used for various biomedical applications such as microactuators, sensors, capacitors, and flexible electronic textiles because of their appealing physical and electrical properties and energy-storage functions. However, to enable application-based specific functionalities (e.g., sensing, responding, and deformation) it is essential that smart stimulus responsive elements be incorporated into the CNT-based materials. A pioneering approach in integrating stimulus responsive molecules or linkers is to utilize multistranded DNA structures, such as i-motif DNA with a four-folded structure, which shows reversible conformational changes upon pH alteration. Herein, a pH-responsive CNT-based hybrid material is developed by conjugating i-motif DNA as a pH-responsive nanosized cross-linker. To fabricate microfibers, we spun the i-motif DNA nanolinker-conjugated CNT-based hybrid material in a proton rich coagulation bath. The attained hybrid microfibers are composed of partially aligned nanowires with similar to 50 nm diameters that are formed in the protonation process by self-assembly of the i-motif DNA nanolinker-conjugated CNT-based hybrid material. The hybrid microfibers showed high electrical conductivity (similar to 27 S/cm), excellent capacitance in a biological medium (similar to 59.9 F/g at pH 5 and similar to 47.8 F/g at pH 8), and stable microactuation without creep behavior. Furthermore, the conjugated i-motif DNA in the hybrid microfibers undergoes conformational changes from a four-folded structure (pH 5) to a random coil structure (pH 8), thus enabling unique dual-pH reversibility in the microfibers, namely switchable microporosity, electrochemical redox activity, and hydrogen peroxide sensing activity. Consequently, the designed stimulus-responsive hybrid microfiber can be used for microactuation and biosensing applications.

ErbB2 signalling, which is amplified by EphA2 binding, is an important therapeutic target for breast cancer. Despite the importance of the EphA2/ErbB2 complex in promoting breast tumorigenesis, the mechanism by which these receptor tyrosine kinases (RTKs) are exported from the endoplasmic reticulum (ER) remains poorly understood. Here we report that the PTB adaptor Anks1a is specifically localized to the ER on its own serine phosphorylation. Once there, Anks1a acts as an important regulator of COPII-mediated EphA2 ER export. The Anks1a ankyrin repeat domain binds EphA2 and causes it to accumulate at sites of ER exit. Simultaneously, the Anks1a PTB domain binds Sec23. This induces internalization of EphA2 via COPII vesicles, while Anks1a remains behind on the ER membrane. EphA2 also binds ErbB2 in the ER and seems to load ErbB2 into growing COPII carriers. Together, our study reveals a novel mechanism that regulates the loading of RTKs into COPII vesicles.

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In Biology, Studies Using Electron Microscopy for making Cell Structure to 3D reconstruction very fast development. Recently, by using Cryo fixation, we can see cell 3D structure without structural change, instead of using chemical fixation which can change cell structure. Before using this technology, we could understand cell structures only in 2D images. But now, through cryo-ET, 3D reconstruction of cell structure without artificial structure changes can be possible and this technology will give us many advantages in Drug delivery and Nanothechnology.

Extract Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007

As one of a number of p53-regulated genes, Gadd45a (growth arrest and DNA damage inducible gene) has been shown to delay carcinogenesis and decrease mutation frequency. Gadd45a is known to regulate nucleotide excision DNA repair (NER) in response to UV radiation. Here, we report an emerging role for Gadd45a in base excision repair (BER). Gadd45a-null mouse embryo fibroblasts MEF and gadd45a-deficient human colon cancer cells exhibited slow BER after treatment with methyl methanesulfonate (MMS) a pure base-damaging agent. In addition, removal of AP sites by apurinic/apyrimidinic endonuclease 1/redox factor 1 (APE1/Ref1) was significantly delayed in gadd45a-null cells. Moreover, the localization of APE1/Ref1 within the nucleus was observed in gadd45a wild-type cells, whereas APE1 become mainly distributed in the cytoplasm, and there is a reduced interaction with proliferating cell nuclear antigen (PCNA) in Gadd45a-deficient cells. Inasmuch as p53 has been shown to regulate BER in addition to the NER pathway, our data suggest that p53-regulated gene Gadd45a contributes to the BER response by affecting the interaction of cellular APE1/Ref1 with PCNA. Gadd45a might be a key component gene of the p53 pathway involved in protection from carcinogenic base damage and maintenance of genomic stability, although the downstream mechanism including APE1/Ref1 will need further study.

The Drosophila retinal cell is widely used to study cell development and cell signaling processes. In the past decades, conventional chemical fixation had been used to study the structure of retinal cells in Droscphila. Rapid freezing methods are superior to chemical fixation methods due to their fixation speed. Some Drosophila tissues, such as the eyes, should not be freezed due to their surrounding cuticle layer. Therefore, in the case of the Drosophila retina, the benefits of high pressure freezing and freeze substitution (HPF-FS) had not been verified. In this study, a retinal cell from Drosophila melanogaster had been studied by using the HPF-FS method. Compared to chemical fixation, the preservation of the cytoplasm in the HPF-FS sample was improved on the whole. The HPF-FS cell membranes were smoother than that of chemical fixation. In addition, HPF-FS preserved the mitochondria structures very well. These results of the present study suggest that HPF-FS is superior to other fixation methods for the preservation of the retinal cell structure.

AIMS/HYPOTHESIS:The aim of this study was to confirm a link between mitochondrial dysfunction and type 2 diabetes.MATERIALS AND METHODS:Cellular levels of mitochondrial proteins, cellular mitochondrial DNA content, and mitochondrial function and morphology were assessed by MitoTracker staining and electron microscopy, in white adipose tissue of 12-week-old male wild-type, obese (ob/ob), and diabetic (db/db) mice.RESULTS:Levels of mitochondrial proteins were found to be very similar in the livers and muscles of all the mice studied. However, levels were greatly decreased in the adipocytes of db/db mice, but not in those of the wild-type and ob/ob mice. Levels of mitochondrial DNA were also found to be considerably reduced in the adipocytes of db/db mice. MitoTracker staining and under electron microscopy revealed that the number of mitochondria was reduced in adipocytes of db/db mice. Respiration and fatty acid oxidation studies indicated mitochondrial dysfunction in adipocytes of db/db mice. Interestingly, there was an increase in mitochondria and mitochondrial protein production in adipocytes of db/db mice treated with rosiglitazone, an agent that enhances insulin sensitivity.CONCLUSIONS/INTERPRETATION:Taken together, these data indicate that mitochondrial loss in adipose tissue is correlated with the development of type 2 diabetes.

Cypermethrin is a potent pesticide derived from natural pyrethrin of the chrysanthemum plant. Cypermethrin has been known to modulate the blood-brain barrier and induce oxidative stress in rats. The oxidative stresses leading to increased reactive oxygen species generation have been identified within the degeneration of the dopaminergic (DA) neuron. However, in testing cypermethrin for its relationship to the degeneration of DA neurons, an experimental study has not yet been done. This study was designed to investigate the effects of cypermethrin on the DA neurons in the substantia nigra of normal and progressive hemiparkinsonian rats. The degree of degeneration of DA neurons was evaluated by tyrosine hydroxylase (TH) immunohistochemistry and forepaw adjusting step (FAS) test. The administration of cypermethrin (15 and 75 mg/kg/day) to the normal rats for 15 days did not decrease the number of TH-immunopositive (TH-IP) DA neurons in the substantia nigra. However, the low dose (15 mg/kg/day) of cypermethrin enhanced the rate of decline of DA neurons in the substantia nigra of hemiparkinsonian rats at 10 days and 3 weeks (p < 0.05). Also, the number of FAS in cypermethrin-treated hemiparkinsonian rats was reduced more rapidly than that of cypermethrin not-treated hemiparkinsonian rats at 10 days, 3 weeks, and 6 weeks (p < 0.05). These results suggest that cypermethrin per se cannot directly induce the degeneration of DA neurons but can accelerate a toxic effect on the degeneration of DA neurons in the progressive hemiparkinsonian rats.

Chronic inhibition of nitric oxide (NO) synthesis by administration of high dose of N(G)-nitro-L-arginine methylester (L-NAME) induces vascular inflammation and subsequent atherosclerosis. We aimed to investigate whether the methanol extract of Sorbus commixta cortex (MSC) is able to prevent inflammatory process in a rat model of L-NAME-induced atherosclerosis. Chronic treatment with low or high doses of MSC prevented the L-NAME-induced increase in monocyte chemoattractant protein-1 (MCP-1) and nuclear factor-kappaB (NF-kappaB) p65 expressions as well as adhesion molecules including intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in aorta. In addition, increased endothelin-1 (ET-1) and angiotensin converting enzyme (ACE) expressions and decreased endothelial cell NO synthase (ecNOS) expression in aorta from L-NAME treated group was reversed by treatment with MSC. From the histological examination, aortic segment from the L-NAME-treated rats revealed a thickening of intima and media, which was ameliorated by treatment with MSC. In conclusion, our results indicate that MSC can prevent atherosclerosis by inhibiting vascular over-expressions of vasoactive materials, pro-inflammatory transcription factor, and adhesion molecules and by augmenting ecNOS in chronic L-NAME-treated rat model.

The present study was designed to examine whether the methanol extract of Sorbus commixta cortex (MSC) could prevent the development of atherosclerosis through regulating the vascular nitric oxide (NO) and endothelin-1 (ET-1) systems in atherogenic-diet rats. Our findings show that aortic NO production as well as endothelial nitric oxide synthase (ecNOS) expression was significantly decreased in atherogenic-diet rats compared with those in the control group. Aortic ET-1 expression was augmented in rats fed an atherogenic-diet while NF-kappaB p65 was upregulated. Treatment of atherogenic-diet rats with either low (100 mg/kg/d) or high (200 mg/kg/d) doses of MSC led not only to significant increases in the aortic NOS/NO system, but also to decreases in aortic ET-1 expression. The aortic expression level of NF-kappaB p65 was also attenuated in atherogenic-diet rats by chronic treatment with low or high doses of MSC. Atherogenic-diet induced increases in the expression of adhesion molecules including intercellular adhesion molecules-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin were markedly decreased by treatment with MSC. From the histopathological examination, MSC treatment was shown to lessen the thickening noted in the aortic intima and media of the atherogenic-diet rats. These results suggest that MSC affects the atherogenic process via the suppression of proinflammatory and adhesion molecules in atherogenic-diet rats, which may be, at least in part, causally related with the regulation of vasoactive systems such as the NO and ET-1 systems.

The present study was designed to examine whether Yukmijihwang-tang (YJT), which is a Korean decoction for the treatment of renal disease, has an effect on renal functional parameters in association with the expression of aquaporin 2 (AQP 2), Na,K-ATPase, heme oxygenase-1 (HO-1) in rats with ischemia/reperfusion-induced acute renal failure (ARF). Polyuria caused by down-regulation of renal AQP 2 in the ischemia/reperfusion-induced ARF rats was markedly restored by administration of YJT (100 or 200mg/kg, p.o.) with restoring expression of AQP 2 in the kidney. The expressions of Na,K-ATPase α1 and β1 subunits in the renal medulla and cortex of the ARF rats were also restored in them by the administration of YJT. Administration of YJT lowered the expression of renal HO-1, which was up-regulated in rats with ischemia/reperfusion-induced ARF. The renal functional parameters including creatinine clearance, urinary sodium excretion, urinary osmolality, and solute-free reabsorption were also markedly restored in ischemia-ARF rats by administration of YJT. Histological study also showed that renal damages in the ARF rats were abrogated by administration of YJT. Taken together, these data indicate that YJT ameliorates renal defects in rats with ischemia/reperfusion-induced ARF.

This paper describes the formation and characterization of liposome entrapping the silver nanoparticles in bilayer. Silver nanoparticles were entrapped in the bilayer of dipalmitoylphosphatidylcholine (DPPC) liposome, named as silver-loaded liposome. Specifically, above the gel to liquid-crystalline phase transition temperature of this lipid (i.e., 41 degrees C), it was observed that membrane fluidities of silver-loaded liposomes were increased, and fluorescence anisotropy values were reduced from 0.114 to 0.097. This might be due to the structural modifications and interactions between DPPC molecules and silver nanoparticles within the bilayer. It was also confirmed that silver nanoparticles were entrapped in hydrophobic region of lipid bilayer with transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) measurements.

Extract HTML view is not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button. Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005