Kalkitoxin attenuates calcification of vascular smooth muscle cells via RUNX-2 signaling pathways.

BACKGROUND: Kalkitoxin (KT) is an active lipopeptide isolated from the cyanobacterium Lyngbya majuscula found in the bed of the coral reef. Although KT suppresses cell division and inflammation, KT's mechanism of action in vascular smooth muscle cells (VSMCs) is unidentified. Therefore, our main aim was to investigate the impact of KT on vascular calcification for the treatment of cardiovascular disease. OBJECTIVES: Using diverse calcification media, we studied the effect of KT on VSMC calcification and the underlying mechanism of this effect. METHODS: VSMC was isolated from the 6 weeks ICR mice. Then VSMCs were treated with different concentrations of KT to check the cell viability. Alizarin red and von Kossa staining were carried out to examine the calcium deposition on VSMC. Thoracic aorta of 6 weeks mice were taken and treated with different concentrations of KT, and H and E staining was performed. Real-time polymerase chain reaction and western blot were performed to examine KT's effect on VSMC mineralization. Calcium deposition on VSMC was examined with a calcium deposition quantification kit. RESULTS: Calcium deposition, Alizarin red, and von Kossa staining revealed that KT reduced inorganic phosphate-induced calcification phenotypes. KT also reduced Ca++-induced calcification by inhibiting genes that regulate osteoblast differentiation, such as runt-related transcription factor 2 (RUNX-2), SMAD family member 4, osterix, collagen 1α, and osteopontin. Also, KT repressed Ca2+-induced bone morphogenetic protein 2, RUNX-2, collagen 1α, osteoprotegerin, and smooth muscle actin protein expression. Likewise, Alizarin red and von Kossa staining showed that KT markedly decreased the calcification of ex vivo ring formation in the mouse thoracic aorta. CONCLUSIONS: This experiment demonstrated that KT decreases vascular calcification and may be developed as a new therapeutic treatment for vascular calcification and arteriosclerosis.

Large colonic lipoma with a laterally spreading tumor treated by endoscopic submucosal dissection: A case report.

BACKGROUND: Since fat does not transmit electrical energy well, delayed perforation and post-polypectomy syndrome due to electrical thermal injury are concerns in the endoscopic removal of colonic lipoma. The endoscopic submucosal dissection (ESD) technique concentrates electrical energy conducts to the submucosa, not the adipose tissue. This helps to minimize electrical thermal injury, especially in the case of large colonic lipomas. In rare cases, such as colonic lipomas accompanied by mucosal lesions, it is difficult for endoscopists to decide how to safely remove them. CASE SUMMARY: A 78-year-old man underwent colonoscopy for colorectal cancer screening. During colonoscopy, a yellowish submucosal tumor with positive cushion sign was observed in the ascending colon measuring about 4.5 cm. A nodular mucosal lesion of about 2.5 cm was observed on the mucosal surface of the lipoma. The lipoma was so large that it occupied much of the inside of the colon, making it difficult to see the entire laterally spreading tumor (LST) at once. The LST was confined to the surface of the lipoma, which had a semipedunculated shape with a wide neck. The margin of the LST was not observed at the neck of the lipoma. ESD was performed and the colonic lipoma with the LST was successfully removed without complications. After 3 d of hospitalization, the patient was discharged without any symptoms. The final pathology report showed that the lesion consisted of submucosal lipoma and tubulovillous adenoma with low-grade dysplasia. CONCLUSION: ESD is effective and safe for treating a large colonic lipoma with an LST by minimizing electrical thermal injury.

Longan extract suppresses food intake through regulation of POMC/AgRP neuronal activities and endoplasmic reticulum stress in hypothalamus of db/db mice.

Type 2 diabetes mellitus (T2DM) is one of the biggest public health issues worldwide and closely related to development of other chronic diseases such as cardiovascular diseases, cancer and neurodegenerative diseases. Considerable percentage of T2DM patients undergo have suffered from binge eating disorder which exacerbates insulin resistance and metabolic challenges. Longan (Dimocarpus longan L.) and its constituents are reported for their various health benefits. However, it is still unknown whether longan fruit supplementation can ameliorate glucose homeostasis and binge eating disorder found in T2DM. The current study aimed to investigate whether longan fruit extract (LE) supplementation can improve diabetic hyperglycemia through modulation of feeding center located in hypothalamus of db/db T2DM mice. As a result, LE supplementation ameliorated fasting blood glucose levels and reduced excessive epididymal fat accumulation. In addition, LE administration improved glucose tolerance and insulin sensitivity in db/db mice. Especially, LE supplemented mice showed less food consumption which was in line with increase of pro-opiomelanocortin (POMC) neuronal activities and decrease of agouti-related peptide (AgRP) neuronal activities. Furthermore, LE supplementation reduced hypothalamic endoplasmic reticulum (ER) stress which was stimulated in db/db mice. As ER stress is a crucial factor involving in appetite control and glucose homeostasis, the effect of LE supplementation on circulating glucose levels and feeding behavior might be mediated by suppression of hypothalamic ER stress. Collectively, these findings suggest that LE could be a potential nutraceutical for improvement of T2DM as well as patients with satiety issues.

Kalkitoxin: A Potent Suppressor of Distant Breast Cancer Metastasis.

Bone metastasis resulting from advanced breast cancer causes osteolysis and increases mortality in patients. Kalkitoxin (KT), a lipopeptide toxin derived from the marine cyanobacterium Moorena producens (previously Lyngbya majuscula), has an anti-metastatic effect on cancer cells. We verified that KT suppressed cancer cell migration and invasion in vitro and in animal models in the present study. We confirmed that KT suppressed osteoclast-soup-derived MDA-MB-231 cell invasion in vitro and induced osteolysis in a mouse model, possibly enhancing/inhibiting metastasis markers. Furthermore, KT inhibits CXCL5 and CXCR2 expression, suppressing the secondary growth of breast cancer cells on the bone, brain, and lungs. The breast-cancer-induced osteolysis in the mouse model further reveals that KT plays a protective role, judging by micro-computed tomography and immunohistochemistry. We report for the first time the novel suppressive effects of KT on cancer cell migration and invasion in vitro and on MDA-MB-231-induced bone loss in vivo. These results suggest that KT may be a potential therapeutic drug for the treatment of breast cancer metastasis.

Inhibition of α-synuclein aggregation by MT101-5 is neuroprotective in mouse models of Parkinson's disease.

Parkinson's disease (PD) is the second most common neurodegenerative disease, after Alzheimer's disease, and becomes increasingly prevalent with age. α-Synuclein (α-syn) forms the major filamentous component of Lewy bodies, which are pathological hallmarks of α-synucleinopathies such as PD. We evaluated the neuroprotective effects of MT101-5, a standardized herbal formula that consists of an ethanolic extract of Genkwae Flos, Clematidis Radix, and Gastrodiae Rhizoma, against α-synuclein-induced cytotoxicity in vivo. MT101-5 protected against behavioral deficits and loss of dopaminergic neurons in human α-syn-overexpressing transgenic mice after treatment with 30 mg/kg/day for 5 months. We investigated transcriptomic changes within MT101-5 mechanisms of action (MOA) suppressing α-syn aggregation in an α-synuclein preformed fibril (α-syn PFF) mouse model of sporadic PD. We found that inhibition of α-syn fibril formation was associated with changes in transcripts in mitochondrial biogenesis, electron transport, chaperones, and proteasomes following treatment with MT101-5. These results suggest that the mixed herbal formula MT101-5 may be used as a pharmaceutical agent for preventing or improving PD.

Pedestrians' behavior based on outdoor thermal comfort and micro-scale thermal environments, Austin, TX.

Cities have faced rapid urbanization, which has changed the impact of the micro-thermal environment on residents' thermal comfort level. Therefore, planners need to understand the city's physical environment so they can identify and ameliorate the effects of the changing in micro-thermal environment. Researchers also need to identify and understand pedestrians' thermal comfort level in street canyons to determine which urban physical factors planners need to improve. This study aimed to observe how thermal comfort affects pedestrian behavior in micro-thermal environments and to determine which urban geometry factors influence pedestrians' thermal comfort. This study collected data in downtown Austin, TX using a mobile weather station, and analyzed the microclimate conditions experienced by pedestrians. A camera mounted on the weather station also allowed us to observe pedestrian behavior patterns. The results revealed that pedestrians tended to choose walking, sitting, and standing locations with high thermal comfort levels such as in the shade on the sidewalk. There was also some correlation between thermal comfort levels and pedestrian behavior patterns. The sky view factor (SVF) and tree canopy coverage ratio (TCR) were also correlated with pedestrians' thermal comfort. This study highlights the need for future research to develop a data collection method for efficient microscopic thermal environment research and a thermal environment estimation and analysis approach from a three-dimensional perspective.

Urban heat island (UHI) intensity and magnitude estimations: A systematic literature review.

The severity of urban heat islands (UHIs) is increasing due to global and urban climate change. The damage caused by UHIs is also increasing. To establish a plan to improve the deteriorating thermal environment in cities due to UHIs and to minimize the damage, further research is needed to accurately estimate and analyze the intensity and magnitude of UHIs. This systematic literature review (SLR) is an in-depth review of 51 studies obtained through a five-step filtering process focusing on their analysis of the spatial extent of UHIs, the UHI concept that was used for UHI estimation, and the UHI estimation and analysis methods. This SLR confirmed the need for accurate UHI intensity and magnitude estimation and analysis to reset the existing UHI classification based on the variety of vertical and horizontal ranges where UHIs occur. The results also indicated that the existing UHI energy concepts for estimating UHIs need to be modified and developed to reflect the three-dimensional physical form of the city. Finally, this SLR clarifies the need to develop an optimized analysis method for UHI research. The review results of this SLR will inform future studies and be the cornerstone for establishing policies and plans that can accurately predict and respond to the damage caused by UHIs.

White matter connectivity differences between treatment responders and non-responders in patients with panic disorder.

BACKGROUND: Panic disorder (PD) is a prevalent and highly disabling mental condition. However, less is known about relationships between biomarkers that may together predict a better response to pharmacological treatment. The objective of the present study was to compare the brain white matter (WM) connectivity between treatment-responsive patients with panic disorder (RPD) and non-responsive patients with panic disorder (NRPD) after 12 weeks of pharmacotherapy. METHODS: Sixty-four patients with PD were enrolled in this study (RPD, n = 37; NRPD, n = 27). All patients were examined by using magnetic resonance imaging at 3 Tesla. The Panic Disorder Severity Scale (PDSS), Albany Panic and Phobia Questionnaire (APPQ), Anxiety Sensitivity Inventory-Revised (ASI-R), Beck Anxiety Inventory (BAI), and Beck Depression Inventory (BDI) were administered at baseline of the study. Fractional anisotropy (FA) data were compared using tract-based spatial statistics (TBSS). RESULTS: TBSS results showed that the FA values of the patients with NRPD were significantly higher than of those with RPD in the WM regions such as the precentral gyrus, parahippocampal gyrus, posterior corona radiata, posterior thalamic radiation, posterior parts of the corpus callosum, and precuneus. Symptom severity scales, such as ASI-R scores, showed significant positive correlations of the FA values with the fronto-temporal WM regions in NRPD. CONCLUSIONS: These results suggest that structural changes to areas such as the fronto-limbic regions and the posterior part of default mode network, could influence medication response in PD. Further studies with a larger number of patients should be performed to confirm our findings.

Subunits of the vacuolar H+-ATPase complex, Vma4 and Vma10, are essential for virulence and represent potential drug targets in Candida albicans.

Hyphal morphogenesis of Candida albicans is important for its pathogenesis. Here, we showed that the filamentous growth of C. albicans requires vacuolar H+-ATPase function. Results showed that levels of Vma4 and Vma10 increased in cells undergoing hyphal growth compared to those undergoing yeast growth. Deleting VMA4 or VMA10 abolished vacuolar functions and hyphal morphogenesis. These deletion mutants were also characterized as avirulent in a mouse model of systemic infection. Furthermore, VMA4 and VMA10 deletion strains showed hypersensitivity to fluconazole, terbinafine, and amphotericin B. Based on these findings, Vma4 and Vma10 are not only involved in vacuole biogenesis and hyphal formation, but also are good targets for antifungal drug development in C. albicans.

Cross-talk between Tor1 and Sch9 regulates hyphae-specific genes or ribosomal protein genes in a mutually exclusive manner in Candida albicans.

The human fungal pathogen Candida albicans switches its morphology from yeast to hyphal forms. The morphological transition may render C. albicans virulent. Several signaling cascades, including those of the cyclic AMP-protein kinase A and mitogen-activated protein kinase pathways, are responsible for morphogenesis. In this study, we observed a reduction in gene transcription of ribosomal proteins during true hyphae formation. Moreover, morphogenesis-dependent decrease in ribosomal protein gene transcription was confirmed in constitutive yeast or filamentous growing strains. We consistently observed that polysome and monosome levels were decreased by hyphal stimuli through TORC1 and Sch9 kinases. Taken together, these results provide several lines of evidence to show that the Tor1-Sch9 kinase cascade, which stimulates transcription of ribosomal protein genes, exists in C. albicans. Thus, the present study revealed a novel link between ribosome biogenesis and morphogenesis in C. albicans that is mediated by Tor1 and Sch9.

Camera-Integrable Wide-Bandwidth Antenna for Capsule Endoscope.

This paper presents a new antenna design for a capsule endoscope. The proposed antenna comprises a camera hole and meandered line. These features enable the antenna to be integrated on the same side as the camera, within the capsule endoscope. Moreover, light-emitting diodes can be mounted on the surface of the antenna for illumination. The antenna achieves a wide bandwidth, despite the small size owing to its meandered line structure.

Thymol inhibits RANKL-induced osteoclastogenesis in RAW264.7 and BMM cells and LPS-induced bone loss in mice.

Thymol was identified as one of key compounds contributing to the aroma of thyme leaves. We investigated the effects of thymol on receptor activator NF-κB ligand (RANKL)-induced osteoclastogenesis in murine macrophage RAW264.7 cells and bone marrow derived macrophage (BMMs) cells and lipopolysaccharide (LPS)-induced bone loss in vivo. Thymol markedly reduced RANKL-stimulated osteoclast formation and differentiation in RAW264.7 cells and BMMs cells without any cytotoxic effects. The in vitro and in vivo osteoclastogenesis inhibitory effect of thymol was assessed by calculating the quantity of TRAP (+) multinucleated cells and its inhibitory effects on the resorbing capacity were examined on calcium phosphate-coated plates. Moreover, the inhibitory effects of thymol resulted in a reduction of RANK, cathepsin K, matrix metalloproteinase-9 (MMP-9), dendritic cell-specific transmembrane protein (DC-STAMP), c-terminal myc kinase (C-MYC), C-terminal Src kinase (C-SRC), GRB2-associated-binding protein 2 (GAB2), microphthalmia-associated transcription factor (MITF), and carbonic anhydrase II genes. Similarly, activities of ERK, JNK and AKT and protein expressions of NFATc1, C-FOS, MMP-9 and cathepsin K were downregulated by thymol. More importantly, the application of thymol significantly reduced LPS-induced inflammatory bone loss in mice. In conclusion, these findings identified that thymol could be a useful therapeutic agent for the prevention of bone destructive diseases.

Mathematical modeling and its analysis for instability of the immune system induced by chemotaxis.

In this paper, we study how chemotaxis affects the immune system by proposing a minimal mathematical model, a reaction-diffusion-advection system, describing a cross-talk between antigens and immune cells via chemokines. We analyze the stability and instability arising in our chemotaxis model and find their conditions for different chemotactic strengths by using energy estimates, spectral analysis, and bootstrap argument. Numerical simulations are also performed to the model, by using the finite volume method in order to deal with the chemotaxis term, and the fractional step methods are used to solve the whole system. From the analytical and numerical results for our model, we explain not only the effective attraction of immune cells toward the site of infection but also hypersensitivity when chemotactic strength is greater than some threshold.

Improvement of pregnancy rate by intrauterine administration of dexamethasone and recombinant human leukemia inhibitory factor at the time of embryo transfer in cattle.

Bovine embryos (day 5) were cultured to day 10 with or without 100 ng/mL PGF2α in medium supplemented with control; 100 nM Dex; 1,000 U/mL recombinant human leukemia inhibitory factor (rhLIF); or Dex+rhLIF. Although the rates to development to the blastocyst were not significantly different among groups, the hatching rate after additional culture with Dex +/or rhLIF was significantly higher in all supplemented groups than the control (p < 0.05). In the presence of PGF2α, the hatching rate was significantly restored in all supplemented groups relative to the group treated with only PGF2α and the control (p < 0.05). Embryo transfer (ET) was performed with blastocysts (day 7). PGF2α levels of control recipient cows were significantly higher in the circulatory blood samples collected 60 min after ET than in samples collected 60 min before ET (p < 0.005), and were decreased in cows injected with loading medium supplemented with Dex+rhLIF (p < 0.005). Pregnancy rate was significantly higher in the ET group that received supplemented embryo-loading medium than in the non-supplemented control (p < 0.05). The intrauterine administration of Dex and rhLIF at ET prevented increased PGF2α in circulatory blood and resulted in enhanced pregnancy rate.

Herbacetin inhibits RANKL-mediated osteoclastogenesis in vitro and prevents inflammatory bone loss in vivo.

Herbacetin is an active flavonol (a type of flavonoid) that has various biologic effects such as antioxidant, antitumor, and anti-inflammatory activities. However, one of its novel effects remains to be investigated, that is, the induction of osteoclastogenesis by the receptor activator of nuclear factor-κB ligand (RANKL). In this study, we examined the effects and mechanisms of action of herbacetin on osteoclastogenesis in RANKL-treated bone marrow-derived macrophages (BMMs) and murine macrophage RAW264.7 cells in vitro and on lipopolysaccharide (LPS)-induced bone destruction in vivo. Herbacetin significantly inhibited RANKL-induced osteoclast formation and differentiation in BMMs and RAW264.7 cells in a dose-dependent manner. Moreover, the suppressive effect of herbacetin resulted in a decrease in osteoclast-related genes, including RANK, tartrate-resistant acid phosphatase, cathepsin K, and matrix metalloproteinase-2 and -9 (MMP-9). Consistent with mRNA results, we confirmed that herbacetin treatment downregulated protein expression of MMP-9 and cathepsin K. Herbacetin also decreased induction of the osteoclastogenic transcription factor c-Fos and nuclear factor of activated T cells c1 (NFATc1) and blocked RANKL-mediated activation of Jun N-terminal kinase (JNK) and nuclear factor-κB. Herbacetin clearly inhibited the bone resorption activity of osteoclasts on plates coated with fluorescein-labeled calcium phosphate. More importantly, the application of herbacetin significantly reduced LPS-induced inflammatory bone loss in mice in vivo. Taken together, our results indicate that herbacetin has potential for use as a therapeutic agent in disorders associated with bone loss.

Association of human microRNAs miR-22 and miR-491 polymorphisms with panic disorder with or without agoraphobia in a Korean population.

BACKGROUND: The possible involvement of microRNAs (miRNA) in psychiatric disorders has been recently recognized. Several miRNA polymorphisms have been found to be associated with panic disorder (PD) in European populations. However, the association of miRNA polymorphisms on PD has not been reported in Asian populations. We evaluated the effect of miR-22 and miR-491 polymorphisms on susceptibility to PD in a Korean population. METHODS: Genotyping for four polymorphic variants of the primary miRNA (pri-miRNA) regions of miR-22 (rs8076112 and rs6502892) and miR-491 (rs4977831 and rs2039391) was performed using blood samples of 341 Korean patients with PD and 229 healthy control subjects. To evaluate PD phenotypes, the Panic Disorder Severity Scale (PDSS) and Anxiety Sensitivity Inventory-Revised (ASI-R) were administered. RESULTS: Three single-nucleotide polymorphisms (SNPs) were found to be associated with PD: rs8076112 miR-22 and rs4977831 and miR-491 rs2039391. The rs8076112C/rs6502892C haplotypes of miR-22 and rs4977831G/rs2039391G and rs4977831A/rs2039391A haplotypes of miR-491 were significantly overrepresented in patients with PD than in healthy control subjects. In combination analysis, miR-22 rs8076112AC/rs6502892CC and rs8076112CC/rs6502892CC and miR-491 rs4977831AG/rs2039391AA were more frequent in patients with PD. Among the phenotype assessments, ASI-R scores were significantly associated with miR-22 rs6502892 in the subgroup with the agoraphobic phenotype. LIMITATIONS: The results should be considered preliminary due to the relatively small sample size and the selection of only four SNPs. CONCLUSIONS: This is the first report to show possible associations of miR-22 and miR-491 with genetic susceptibility to PD in a Korean population.

Herbacetin inhibits inducible nitric oxide synthase via JNK and nuclear factor-κB in LPS-stimulated RAW264.7 cells.

Herbacetin (3,4',5,7,8-pentahydroxyflavone), an active flavonol compound within flavonoid, has been shown to induce apoptosis in HepG2 cells and suppress hepatocyte growth factor-induced motility of human breast cancer MDA-MB-231 cells. However, the anti-inflammatory mechanisms of Herbacetin have not been researched. In this study, we examined the inflammatory responses stimulated by lipopolysaccharide (LPS) in RAW264.7 macrophage cells after pretreatment with different concentrations of Herbacetin. We found that Herbacetin decreased nitric oxide (NO) production in LPS-induced RAW264.7 and mouse bone marrow-derived macrophages. In addition, Herbacetin inhibited the LPS-induced expression of inducible nitric oxide synthase mRNA and protein in RAW264.7 cells. Treatment with Herbacetin decreased the release of proinflammatory cytokines, including TNF-α and IL-1ß. Moreover, Herbacetin inhibited the activity of JNK kinase and nuclear factor-κB, signaling molecules involved in NO production. Cell signaling analysis using Bay 11-7082 (an inhibitory κB kinase 2 inhibitor) and mitogen-activated protein kinase (MAPK) inhibitors (SB203580 for p38, SP600125 for JNK, and PD 98059 for ERK) suggested that LPS induced iNOS expression via activation of the JNK and NF-κB pathway, but not the p38 and ERK pathway. These findings suggest that Herbacetin exerts an anti-inflammatory effect through suppression of LPS-induced JNK and NF-κB signaling pathways and diminished production of proinflammatory cytokines and mediators.

The additional value of attenuation correction CT acquired during 18F-FDG PET/CT in differentiating mature from immature teratomas.

INTRODUCTION: Increased F-FDG uptake is often seen in soft-tissue components or in neuronal components of teratomas, which makes differentiation of mature and immature teratoma difficult using only F-FDG uptake. The distribution pattern of fat and calcification in teratomas is characteristic on CT, which can also be well seen on attenuation correction CT (AC-CT). We hypothesize that the fat and calcification distribution patterns on AC-CT taken during PET/CT will provide additional diagnostic information in differentiating between mature and immature teratomas. PATIENTS AND METHODS: This retrospective study included 34 patients (44 masses; mean age 32 ± 16.3 years, range 0.2-70 years) who underwent F-FDG PET/CT before surgical resection for teratomas. F-FDG equal to or higher than the liver was visually considered positive. AC-CT images acquired during PET/CT were reviewed for calcification and fat distribution patterns. AC-CT findings for immature teratomas were scattered fat and/or disperse coarse calcification. Pathologic results were categorized into mature and immature teratomas. SUVmax and AC-CT findings were correlated with pathologic results. RESULTS: Out of the 44 lesions, 11 teratomas were immature, with higher F-FDG uptake in these tumors (7.8 ± 4.10 vs. 2.1 ± 2.28, P < 0.001). SUVmax higher than 2.8 were 91% accurate, but fat and/or calcification patterns on AC-CT were extremely helpful in reducing false-positive findings based on F-FDG uptake alone. CONCLUSION: Characteristic fat and calcification patterns on AC-CT of PET/CT were extremely helpful in differentiating mature from immature teratomas, especially in mature teratomas with increased F-FDG uptake. This can potentially reduce unnecessary radiation exposure from additional contrast-enhanced CT.

Insights into noncanonical E1 enzyme activation from the structure of autophagic E1 Atg7 with Atg8.

Autophagy is the degradation of cellular organelles via the lysosomal pathway. The autophagic ubiquitin-like (Ubl) molecule Atg8 is activated by the E1-like enzyme Atg7. As this noncanonical E1 enzyme's domain organization is unique among Ubl-activating E1 enzymes, the structural basis for its interactions with Atg8 and partner E2 enzymes remains obscure. Here we present the structure of the N-terminal domain of Atg7, revealing a unique protein fold and interactions with both autophagic E2 enzymes Atg3 and Atg10. The structure of the C-terminal domain of Atg7 in complex with Atg8 shows the mode of dimerization and mechanism of recognition of Atg8. Notably, the catalytic cysteine residue in Atg7 is positioned close to the C-terminal glycine of Atg8, its target for thioester formation, potentially eliminating the need for large conformational rearrangements characteristic of other E1s.

Trichostatin A promotes the development of bovine somatic cell nuclear transfer embryos.

We studied the effects of trichostatin A (TSA), a histone deacetylase inhibitor, on the development of bovine somatic cell nuclear transfer (SCNT) embryos by investigating (1) the optimal concentration and treatment time of TSA for development of bovine SCNT embryos, (2) the status of histone acetylation in TSA-treated and control SCNT embryos and (3) the expression of histone acetylation- and deacetylation-related genes in TSA-treated and control SCNT embryos. We observed that 50 nM TSA-treatment for 20 h following fusion resulted in more efficient in vitro development of bovine SCNT embryos to the blastocyst stage. In regard to histone H4K5 acetylation, half of the control SCNT embryos faintly displayed histone H4K5 signals 30 min after electrofusion, while most of the TSA-treated SCNT embryos displayed histone H4K5 signals within 30 min after electrofusion. Furthermore, the expressions of HDAC1 and HDAC2 in the blastocysts were significantly lower (P<0.05) in the TSA-treated SCNT than in the control SCNT. However, the expression of GCN5 and HAT1 did not differ between the TSA-treated and control SCNT. In conclusion, we demonstrated that TSA-treatment after SCNT in bovine embryos can dramatically improve the practical applications of current cloning techniques.