Engineering TALE-linked deaminases to facilitate precision adenine base editing in mitochondrial DNA.

DddA-derived cytosine base editors (DdCBEs) and transcription activator-like effector (TALE)-linked deaminases (TALEDs) catalyze targeted base editing of mitochondrial DNA (mtDNA) in eukaryotic cells, a method useful for modeling of mitochondrial genetic disorders and developing novel therapeutic modalities. Here, we report that A-to-G-editing TALEDs but not C-to-T-editing DdCBEs induce tens of thousands of transcriptome-wide off-target edits in human cells. To avoid these unwanted RNA edits, we engineered the substrate-binding site in TadA8e, the deoxy-adenine deaminase in TALEDs, and created TALED variants with fine-tuned deaminase activity. Our engineered TALED variants not only reduced RNA off-target edits by >99% but also minimized off-target mtDNA mutations and bystander edits at a target site. Unlike wild-type versions, our TALED variants were not cytotoxic and did not cause developmental arrest of mouse embryos. As a result, we obtained mice with pathogenic mtDNA mutations, associated with Leigh syndrome, which showed reduced heart rates.

First Report of Passiflora Latent Virus Infecting Passion Fruit (Passiflora edulis) in South Korea.

Passion fruit (Passiflora edulis) viral diseases caused by papaya leaf curl Guangdong virus, cucumber mosaic virus, East Asian Passiflora virus, and euphorbia leaf curl virus have been reported in South Korea (Joa et al. 2018; Kim et al. 2018). In June 2021, virus-like symptoms, e.g., mosaic pattern, curling, chlorosis, and deformation, were observed on leaves and fruits of greenhouse-grown P. edulis in Iksan, South Korea, with disease incidence greater than 2% (300 plants: 8 symptomatic plants and 292 asymptomatic plants). Total RNA was extracted from a pooled sample of symptomatic leaves of an individual P. edulis plant using the RNeasy Plant Mini Kit (Qiagen, Germany), and a transcriptome library was generated using the TruSeq Stranded Total RNA LT Sample Prep Kit (Illumina, San Diego, CA). Next-Generation Sequencing (NGS) was performed using the Illumina NovaSeq 6000 system (Macrogen Inc., Korea). De novo assembly of the resulting 121,154,740 reads was performed using Trinity (Grabherr et al. 2011). A total of 70,895 contigs was assembled (>200 bp) and annotated against the NCBI viral genome database using BLASTn (ver. 2.12.0). One 827-nt contig was annotated as milk vetch dwarf virus (MVDV), a member of the genus Nanovirus in the family Nanoviridae (Bangladesh isolate, acc. no. LC094159, 96.0% nucleotide identity), and the other 3,639-nt contig corresponded to Passiflora latent virus (PLV), a member of the genus Carlavirus in the family Betaflexiviridae (Israel isolate, acc. no. DQ455582, 90.0% nucleotide identity). For further confirmation, total RNA was isolated from symptomatic leaves of the same P. edulis used for NGS analysis using a viral gene spin DNA/RNA extraction kit (iNtRON Biotechnology, Seongnam, Korea), and reverse transcription polymerase chain reaction (RT-PCR) was performed using specific primers: PLV-F/R (5'-GTGCCCACCGAACATGTTACCTC-3'/5'-CCATGCACTTGGAATGCTTACCC-3') targeting the coat protein region of PLV, MVDV-M-F/R (5'-CTAGTCAGCCATCCAATGGTG-3'/5'-GTGCAGGGTTTGATTGTCTGC-3') targeting the movement protein region, and MVDV-S-F/R (5'-GGATTTTAATACGCGTGGACGATC-3'/5'-AACGGCTATAAGTCACTCCGTAC-3') targeting the coat protein region of MVDV. An expected PCR product of 518 bp corresponding to PLV was amplified, while MVDV was not detected. The amplicon was directly sequenced, and its nucleotide sequence was deposited in GenBank (acc. no. OK274270). A BLASTn analysis showed that the nucleotide sequence of the PCR product shared 93.0% and 96.2% identity with PLV isolates from Israel (MH379331) and Germany (MT723990), respectively. In addition, six passion fruit leaves and two fruit samples with PLV-like symptoms were collected from a total of eight plants grown in the greenhouse in Iksan for RT-PCR analysis, and six samples tested positive for PLV. However, PLV was not detected in one leaf and one fruit among all samples. Mechanical sap inoculation was conducted using extracts of systemic leaves as inoculum on P. edulis and the indicator plants Chenopodium quinoa, Nicotiana benthamiana, N. glutinosa, and N. tabacum. In P. edulis, vein chlorosis and yellowing on systemic leaves were observed 20 days post inoculation (dpi). Necrotic local lesions were observed on inoculated leaves of N. benthamiana and N. glutinosa 15 dpi, and PLV infection was confirmed by RT-PCR assay in symptomatic leaf tissue. This study aimed to determine whether commercially grown passion fruit in the southern part of South Korea could be infected with and potentially spread PLV. Whereas PLV was asymptomatic in persimmon (Diospyros kaki) in South Korea, no pathogenicity testing in passion fruit was reported (Cho et al. 2021). Here, we have shown the natural infection of passion fruit with PLV in South Korea for the first time and associated infection with obvious symptoms. This suggests a need to evaluate potential losses in passion fruit and the selection of healthy propagation material.

The Functional Association of ACQOS/VICTR with Salt Stress Resistance in Arabidopsis thaliana Was Confirmed by CRISPR-Mediated Mutagenesis.

Clustered regularly interspaced palindromic repeat (CRISPR)-mediated mutagenesis has become an important tool in plant research, enabling the characterization of genes via gene knock-out. CRISPR genome editing tools can be applied to generate multi-gene knockout lines. Typically, multiple single-stranded, single guide RNAs (gRNAs) must be expressed in an organism to target multiple genes simultaneously; however, a single gRNA can target multiple genes if the target genes share similar sequences. A gene cluster comprising ACQUIRED OSMOTOLERANCE (ACQOS; AT5G46520) and neighboring nucleotide-binding leucine-rich repeats (NLRs; AT5G46510) is associated with osmotic tolerance. To investigate the role of ACQOS and the tandemly arranged NLR in osmotic tolerance, we introduced small insertion/deletion mutations into two target genes using a single gRNA and obtained transformant plant lines with three different combinations of mutant alleles. We then tested our mutant lines for osmotic tolerance after a salt-stress acclimation period by determining the chlorophyll contents of the mutant seedlings. Our results strongly suggest that ACQOS is directly associated with salt resistance, while the neighboring NLR is not. Here, we confirmed previous findings suggesting the involvement of ACQOS in salt tolerance and demonstrated the usefulness of CRISPR-mediated mutagenesis in validating the functions of genes in a single genetic background.

ß-Cell protection and antidiabetic activities of Crassocephalum crepidioides (Asteraceae) Benth. S. Moore extract against alloxan-induced oxidative stress via regulation of apoptosis and reactive oxygen species (ROS).

BACKGROUND: Medicinal plants are becoming more popular in the treatment of various diseases because of the adverse effects of the current therapy, especially antioxidant plant components such as phenols and flavonoids have a protective role against oxidative stress-induced degenerative diseases like diabetes. Thus, the purpose of this study was to investigate ß-cell protection and antidiabetic activities of Crassocephalum crepidioides (Asteraceae) Benth. S. Moore. METHOD: The in-vitro study was conducted by the pancreatic ß-cell culture and α-amylase inhibition technique which includes two methods, namely starch-iodine method and 3,5-dinitrosalicylic acid (DNSA) method. On the other hand, the in-vivo study was performed by oral glucose tolerance test (OGTT) method and alloxan-induced diabetes method by using Wistar albino rat. At the end pancreatic specimens were removed and processed for histopathological study. RESULT: The plant extract showed significant (*p < 0.05, **p < 0.01) effect on hyperglycemia as compared to standard (Gliclazide) in OGTT. The plant extract showed efficient protection activity of pancreatic ß-cell from cell death in INS-1 cell line by significantly reduced (*p < 0.05, **p < 0.01) the levels alloxan-induced apoptosis and intracellular reactive oxygen species (ROS) accumulation. In addition, the plant extract showed a significant (*p < 0.05, **p < 0.01) effect on hyperglycemia by increases in percent of ß-cells present in each islet (45% - 60%) compared to the diabetic group. CONCLUSION: The result showed that C. crepidioides had ß-cell protection and antidiabetic activities in pancreatic ß-cell culture and Wistar albino rat.

Polyphenolic Extract of Euphorbia supina Attenuates Manganese-Induced Neurotoxicity by Enhancing Antioxidant Activity through Regulation of ER Stress and ER Stress-Mediated Apoptosis.

Manganese (Mn) is an important trace element present in human body, which acts as an enzyme co-factor or activator in various metabolic reactions. While essential in trace amounts, excess levels of Mn in human brain can produce neurotoxicity, including idiopathic Parkinson's disease (PD)-like extrapyramidal manganism symptoms. This study aimed to investigate the protective role of polyphenolic extract of Euphorbia supina (PPEES) on Mn-induced neurotoxicity and the underlying mechanism in human neuroblastoma SKNMC cells and Sprague-Dawley (SD) male rat brain. PPEES possessed significant amount of total phenolic and flavonoid contents. PPEES also showed significant antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and reducing power capacity (RPC) assays. Our results showed that Mn treatment significantly reduced cell viability and increased lactate dehydrogenase (LDH) level, which was attenuated by PPEES pretreatment at 100 and 200 µg/mL. Additionally, PPEES pretreatment markedly attenuated Mn-induced antioxidant status alteration by resolving the ROS, MDA and GSH levels and SOD and CAT activities. PPEES pretreatment also significantly attenuated Mn-induced mitochondrial membrane potential (ΔΨm) and apoptosis. Meanwhile, PPEES pretreatment significantly reversed the Mn-induced alteration in the GRP78, GADD34, XBP-1, CHOP, Bcl-2, Bax and caspase-3 activities. Furthermore, administration of PPEES (100 and 200 mg/kg) to Mn exposed rats showed improvement of histopathological alteration in comparison to Mn-treated rats. Moreover, administration of PPEES to Mn exposed rats showed significant reduction of 8-OHdG and Bax immunoreactivity. The results suggest that PPEES treatment reduces Mn-induced oxidative stress and neuronal cell loss in SKNMC cells and in the rat brain. Therefore, PPEES may be considered as potential treat-ment in Mn-intoxicated patients.

Turmeric extract and its active compound, curcumin, protect against chronic CCl4-induced liver damage by enhancing antioxidation.

BACKGROUND: Curcumin, a major active component of turmeric, has previously been reported to alleviate liver damage. Here, we investigated the mechanism by which turmeric and curcumin protect the liver against carbon tetrachloride (CCl4)-induced injury in rats. We hypothesized that turmeric extract and curcumin protect the liver from CCl4-induced liver injury by reducing oxidative stress, inhibiting lipid peroxidation, and increasing glutathione peroxidase activation. METHODS: Chronic hepatic stress was induced by a single intraperitoneal injection of CCl4 (0.1 ml/kg body weight) into rats. Turmeric extracts and curcumin were administered once a day for 4 weeks at three dose levels (100, 200, and 300 mg/kg/day). We performed ALT and AST also measured of total lipid, triglyceride, cholesterol levels, and lipid peroxidation. RESULT: We found that turmeric extract and curcumin significantly protect against liver injury by decreasing the activities of serum aspartate aminotransferase and alanine aminotransferase and by improving the hepatic glutathione content, leading to a reduced level of lipid peroxidase. CONCLUSIONS: Our data suggest that turmeric extract and curcumin protect the liver from chronic CCl4-induced injury in rats by suppressing hepatic oxidative stress. Therefore, turmeric extract and curcumin are potential therapeutic antioxidant agents for the treatment of hepatic disease.

Comparison of TGF-ß, PDGF, and CTGF in hepatic fibrosis models using DMN, CCl4, and TAA.

Three chemotoxins including dimethylnitrosamine (DMN), carbon tetrachloride (CCl4), and thioacetamide (TAA) are commonly used in hepatofibrotic models. We aimed to draw characteristics of histopathology and pro-fibrogenic cytokines including TGF-ß, PDGF and CTGF among three models. Rats were divided into six groups and intra-peritoneally injected with DMN (10 mg/kg, for three weeks, three consecutive days weekly), CCl4 (1.6 g/kg, for 10 weeks, twice weekly), TAA (200 mg/kg, for 12 weeks, twice weekly) or their corresponded treatment for each control group. The liver weights were decreased in DMN model, but not other models. Ascites were occurred as 3-, 2-, and 7-rats in DMN, CCl4, and TAA model, respectively. The lipid peroxidation was highest in CCl4 model, serum levels of liver enzymes were increased as similar severity. The hepatofibrotic alterations were remarkable in DMN and TAA model, but not CCl4 as evidenced by the Masson trichrome staining and hydroxyproline. The immunohistochemistry for α-SAM showed that the DMN model was most severely enhanced than other models. On the other hand, hepatic tissue levels of pro-fibrogenic cytokines including TGF-ß, PDGF, and CTGF were generally increased in three models, but totally different among models or measurement resources. Especially, serum levels of three cytokines were remarkably increased by CCl4 injection and CTGF levels in both hepatic tissue and serum were highest in CCl4 group. Our results firstly demonstrated comparative study for features of morphological finding and pro-fibrogenic cytokines in serum and hepatic protein levels among three models. Above results would be a helpful reference for hepatofibrotic studies.

Larval chigger mites collected from small mammals in 3 provinces, Korea.

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals.

Analysis of the early-flowering mechanisms and generation of T-DNA tagging lines in Kitaake, a model rice cultivar.

As an extremely early flowering cultivar, rice cultivar Kitaake is a suitable model system for molecular studies. Expression analyses revealed that transcript levels of the flowering repressor Ghd7 were decreased while those of its downstream genes, Ehd1, Hd3a, and RFT1, were increased. Sequencing the known flowering-regulator genes revealed mutations in Ghd7 and OsPRR37 that cause early translation termination and amino acid substitutions, respectively. Genetic analysis of F2 progeny from a cross between cv. Kitaake and cv. Dongjin indicated that those mutations additively contribute to the early-flowering phenotype in cv. Kitaake. Because the short life cycle facilitates genetics research, this study generated 10 000 T-DNA tagging lines and deduced 6758 flanking sequence tags (FSTs), in which 3122 were genic and 3636 were intergenic. Among the genic lines, 367 (11.8%) were inserted into new genes that were not previously tagged. Because the lines were generated by T-DNA that contained the promoterless GUS reporter gene, which had an intron with triple splicing donors/acceptors in the right border region, a high efficiency of GUS expression was shown in various organs. Sequencing of the GUS-positive lines demonstrated that the third splicing donor and the first splicing acceptor of the vector were extensively used. The FST data have now been released into the public domain for seed distribution and facilitation of rice research.

Spotted fever group rickettsia closely related to Rickettsia monacensis isolated from ticks in South Jeolla province, Korea.

Rickettsia monacensis, a spotted fever group rickettsia, was isolated from Ixodes nipponensis ticks collected from live-captured small mammals in South Jeolla province, Korea in 2006. Homogenates of tick tissues were inoculated into L929 and Vero cell monolayers using shell vial assays. After several passages, Giemsa staining revealed rickettsia-like organisms in the inoculated Vero cells, but not the L929 cells. Sequencing analysis revealed that the ompA-small part (25-614 bp region), ompA-large part (2849-4455 bp region), nearly full-length ompB (58-4889 bp region) and gltA (196-1236 bp region) of the isolates had similarities of 100%, 99.8%, 99.3% and 99.5%, respectively, to those of R. monacensis. Furthermore, phylogenetic analysis showed that the isolate was grouped into the cluster in the same way as R. monacensis in the trees of all genes examined. These results strongly suggest that the isolate is closely related to R. monacensis. As far as is known, this is the first report of isolation of R. monacensis from ticks in Korea.

Alpha (1,2)-fucosyltransferase M307A polymorphism improves piglet survival.

To confirm the beneficial effects of alpha (1,2)-fucosyltransferase (FUT1) M307 (A) on piglet survival on commercial farms, we performed PCR-RFLP analysis of FUT1 M307 in successfully marketed (n = 245) and disease affected/deceased pigs during weaning (n = 252) at a commercial farm. We also evaluated the FUT1 genotypes of 190 healthy pigs from three different genetic backgrounds. The distribution of genotypes differed between the successfully marketed and disease affected/deceased pig groups. The frequency of the A allele, associated with resistance to edema and post-weaning diarrhea, was higher in the post-weaning survival group (0.21) than in the non-survival group (0.16, P < 0.05). The odds ratio for piglet survival between AA and GG genotypes was 1.98; thus, piglet survival for individuals with the AA genotype was almost two-fold greater than for GG individuals. The FUT1 gene polymorphism can be used as an effective marker for selection programs to improve post-weaning piglet survival.

Detection of Rickettsia monacensis from Ixodes nipponensis collected from rodents in Gyeonggi and Gangwon Provinces, Republic of Korea.

A total of 1,305 ticks were collected from wild rodents captured monthly, except July and August, during 2008 at three US-ROK operated military training sites and three US military installations in Gyeonggi and Gangwon Provinces, the Republic of Korea (ROK). Ixodes nipponensis was the most frequently collected tick (n = 1,299, 99.5 %), followed by Ixodes pomerantzevi (n = 6, 0.5 %). The ticks were pooled (1-15/sample) and tested by nested polymerase chain reaction (nPCR) for spotted fever group (SFG) rickettsiae with primer sets targeting the outer membrane protein B (ompB), citrate synthase (gltA), and 17-kDa antigen gene loci. A total of 115/197 (58.4 %) pools were positive by nPCR for the outer membrane protein ompB. Nucleotide sequence analysis of 105/115 (91.3 %) ompB targeted nPCR positive products showed a high degree of similarity to Rickettsia monacensis (99.3-100 %, n = 87) and R. japonica (99.5-100 %, n = 18). From the 87 positive samples demonstrating a high degree of similarity to R. monacensis, 15 were selected and analyzed by nPCR for gltA and the 17-kDa genes. A total of 12/15 pooled samples were positive for by nPCR for gltA, with amplicons demonstrating a high degree of similarity to R. monacensis (99.3-99.7 %). A total of 13/15 pooled samples were positive by nPCR for the 17-kDa gene, with amplicons demonstrating a high degree of similarity to R. monacensis (99.4-100 %). These findings demonstrate that R. monacensis is distributed throughout Gyeonggi and Gangwon Provinces in the ROK. Furthermore, data suggest a relative high prevalence of R. monacensis in the tick, I. nipponensis.

Hepatoprotective effect of Amomum xanthoides against dimethylnitrosamine-induced sub-chronic liver injury in a rat model.

CONTEXT: Amomum xanthioides Wall. ex Baker (Zingiberaceae) is a tropical medicinal plant that is commonly utilized in the treatment of digestive system disorders in Asia for a long time. OBJECTIVE: This study aimed to evaluate the hepatoprotective effect and related mechanisms of A. xanthoides. MATERIALS AND METHODS: Sub-chronic liver injury was induced by dimethylnitrosamine (DMN, 10 mg/kg, three times per week for 3 weeks, i.p.) in rats. Water extract of A. xanthoides (WAX, 50 and 100 mg/kg) was given once a day for 3 weeks. RESULTS AND CONCLUSION: WAX (100 mg/kg) significantly attenuated the DMN-induced excessive release of alanine aminotransferase (123.6 IU/L), aspartate aminotransferase (227.9 IU/L), alkaline phosphatase (820.9 IU/L) and total bilirubin (0.50 g/dL) in serum (p < 0.01), and hydroxyproline (30.5 mg/g tissue) and malondialdehyde (MDA) (53.6 µM/g tissue) contents (p < 0.01) in liver tissue. Furthermore, WAX significantly ameliorated the depletion of total antioxidant capacity (2.54 µM/mg tissue), superoxide dismutase (0.30 U/mg tissue), glutathione (2.10 µM/mg tissue) and catalase (605.0 U/mg tissue) activities (p < 0.05 or p < 0.01) in liver tissue. Histopathological and immunohistochemical analyses indicated that WAX markedly reduced inflammation, necrosis, collagen accumulation and activation of hepatic satellite cells in the liver. Our findings demonstrated that A. xanthoides exerts favorable hepatoprotective effects via positive regulation of the antioxidative system.

Evaluation of the Weeds around Capsicum annuum (CA) Cultivation Fields as Potential Habitats of CA-Infecting Viruses.

Capsicum annuum (CA) is grown outdoors across fields in Jeollabuk-do, South Korea. The weeds surrounding these fields were investigated regarding the infection of 11 viruses infecting CA during the year 2014-2018. In the reverse transcription polymerase chain reaction diagnosis, 546 out of 821 CA samples (66.5%) were infected by nine viruses, and 190 out of 918 weed samples (20.7%) were infected by eight viruses. Correlation analysis of the mutual influence of the viruses infecting CA and weeds during these 5 years showed that five viruses had significant positive correlations with the infection in both CA and weeds. Over the study period, the weeds infected by cucumber mosaic virus (CMV) in the previous year were positively correlated with the incidence of CMV infection in CA in the current year, although the correlation was lower for tomato spotted wilt virus (TSWV) compared to CMV. The CMV infection percent was 14.0% in summer annuals, 11.4% in perennials, and 7.8% in winter annuals. However, considering the overwintering period without CA, the infection percent was 5.2% higher in winter annuals and perennials than that in summer annuals, indicating that winter annual and perennial weeds served as the main habitats for insect vectors. The TSWV infection percent in weeds was 10.4% in summer annuals, 6.4% in winter annuals, and 6.2% in perennials. The weeds surrounding CA fields, acting as the intermediate hosts, were found to be the potent sources of infection, influencing the spread and diversity of CA-infecting viruses. The results of this study can contribute to prevent viral infection in agricultural fields.

Effects of Short-Term Intake of Montmorency Tart Cherry Juice on Sleep Quality after Intermittent Exercise in Elite Female Field Hockey Players: A Randomized Controlled Trial.

The purpose of this study was to investigate the effect of short-term consumption of tart cherry juice on levels of cortisol and melatonin and sleep quality after intermittent exhaustion exercise in female elite field hockey players. A total of 19 field hockey players participated in the present study for 5 days. The individuals were divided into the placebo group (PLA, n = 9) and the tart cherry juice group (TCJ, n = 10), respectively. Actigraphy devices were distributed to analyze sleep quality and participants were required to wear the device while sleeping until the study was completed. Participants consumed tart cherry juice or placebo drinks five times in a total of 48 h while double-blinded after intermittent exhaustion exercise. A significant interaction effect (group × time) between PLA and TCJ groups was not observed in the levels of melatonin and cortisol. The variables of sleep quality showed significant interaction effects with regards to the total time in bed (TTB; p = 0.015), wake after sleep onset (WASO; p = 0.044), and movement index (MI; p = 0.031) variables. As a result, our study confirmed the possibility that the short-term intake of tart cherry juice could not change the levels of melatonin and cortisol in elite female hockey players but could help improve their sleep quality.

The efficacy of CRISPR-mediated cytosine base editing with the RPS5a promoter in Arabidopsis thaliana.

CRISPR/Cas9-mediated genome editing is an important and versatile technology in modern biological research. Recent advancements include base-editing CRISPR tools that enable targeted nucleotide substitutions using a fusion protein comprising a nickase variant of Cas9 and a base deaminase. Improvements in base editing efficiencies and inheritable of edited loci need to be made to make CRISPR a viable system in plants. Here, we report efficiency of cytosine base editors (CBEs) in Arabidopsis thaliana by applying the strong endogenous RPS5a promoter to drive the expression of nickase Cas9 and either rAPOBEC1 from rat (BE3) or the PmCDA1 activation-induced cytidine deaminase from sea lamprey (AIDv2). Compared with the strong heterologous CaMV35S promoter of viral origin, the RPS5a promoter improved CBE efficiency by 32% points with the number of T1 plants showing over 50% conversion ratio when the LFY gene was targeted. CBE induced nonsense mutations in LFY via C-to-T conversion, which resulted in loss-of-function lfy phenotypes; defects in LFY function were associated with the targeted base substitutions. Our data suggest that optimal promoter choice for CBE expression may affect base-editing efficiencies in plants. The results provide a strategy to optimize low-efficiency base editors and demonstrate their applicability for functional assays and trait development in crop research.

Cardioprotective Potential of an SGLT2 Inhibitor Against Doxorubicin-Induced Heart Failure.

BACKGROUND AND OBJECTIVES: Recent studies have shown that sodium-glucose co-transporter 2 (SGLT2) inhibitors reduce the risk of heart failure (HF)-associated hospitalization and mortality in patients with diabetes. However, it is not clear whether SGLT2 inhibitors have a cardiovascular benefit in patients without diabetes. We aimed to determine whether empagliflozin (EMPA), an SGLT2 inhibitor, has a protective role in HF without diabetes. METHODS: Cardiomyopathy was induced in C57BL/6J mice using intraperitoneal injection of doxorubicin (Dox). Mice with HF were fed a normal chow diet (NCD) or an NCD containing 0.03% EMPA. Then we analyzed their phenotypes and performed in vitro experiments to reveal underlying mechanisms of the EMPA's effects. RESULTS: Mice fed NCD with EMPA showed improved heart function and reduced fibrosis. In vitro studies showed similar results. Phloridzin, a non-specific SGLT inhibitor, did not show any protective effect against Dox toxicity in H9C2 cells. SGLT2 inhibitor can cause increase in blood ketone levels. Beta hydroxybutyrate (ßOHB), which is well known ketone body associated with SGLT2 inhibitor, showed a protective effect against Dox in H9C2 cells and in Dox-treated mice. These results suggest elevating ßOHB might be a convincing mechanism for the protective effects of SGLT2 inhibitor. CONCLUSIONS: SGLT2 inhibitors have a protective effect in Dox-induced HF in mice. This implied that SGLT2 inhibitor therapy could be a good treatment strategy even in HF patients without diabetes.

Eucommia ulmoides leaf (EUL) extract enhances NO production in ox-LDL-treated human endothelial cells.

Eucommia ulmoides leaves (EULs), referred to as Du-zhong, are utilized to lower blood pressure and improve liver and kidney tone, and also have been applied to cardiovascular disease in Korea, China, and Japan. Endothelial dysfunction, which is caused by endothelial nitric oxide synthase (eNOS) uncoupling, is an initial step in atherosclerosis. In this study, we investigated the protective effects of EUL aqueous extract against ox-LDL-induced eNOS uncoupling and its possible mechanisms in human umbilical vein endothelial cells (HUVECs). A EUL component, aucubin, was also applied to ox-LDL-exposed HUVECs. Whereas ox-LDL significantly decreased nitric oxide (NO) levels in HUVECs, EUL extract and aucubin led to significant recovery of NO levels. When treated with ox-LDL in the presence of EUL extracts or aucubin, O2- production was markedly reduced in HUVECs compared to treatment with ox-LDL alone. EUL extract and aucubin also led to recovery of phospho-eNOS Thr495 expression, a critical signaling component in eNOS uncoupling, suggesting that EUL has regulatory effects against eNOS uncoupling and might play preventive/regulatory roles against vascular endothelial dysfunction.