Digital health interventions to promote healthy lifestyle in hemodialysis patients: an interventional pilot study.

Low physical activity has been associated with poor prognosis in hemodialysis (HD) patients. Interventions to maintain healthy lifestyle in this population are important to reduce mortality. This study aimed to evaluate the effectiveness of digital health interventions (DHIs) for improving the physical activity and health-related quality of life (HRQoL) in HD patients. The 24-week prospective study enrolled 31 clinically stable HD patients. All participants were assigned home exercises and provided with wearable devices. Dietary and exercise information was uploaded to a health management platform. Suggestions about diet and exercise were provided, and a social media group was created. Physical performance testing was performed at baseline and during weeks 4, 8, 12, 16 and 24. HRQoL and nutritional status were evaluated. A total of 25 participants completed the study. After the interventions, the daily step count increased 1658 steps. The 10-time-repeated sit-to-stand test reduced by 4.4 s, the sit-to-stand transfers in 60 s increased 12 repetitions, the distance of six-minute walk test (6MWT) increased by 55.4 m. The mental health components and burden of kidney disease of the Kidney Disease Quality of Life survey, and subjective global assessment (SGA) scores improved. By Spearman correlation, the monthly step count correlated positively with 6MWT and SGA. DHIs that combined wearable devices, a health management platform, and social media could strengthen physical activity and improve the HRQoL and nutrition of maintenance HD patients. The results outline a new model to promote healthy lifestyle behaviors in HD patients.

Can peripheral biomarkers reflect the psychological condition in geriatric populations? The influence of cardiovascular comorbidities.

BACKGROUND: Although previous studies indicated the association between peripheral biomarkers and psychological conditions, a higher prevalence of cardiovascular diseases (CVD) among geriatric populations may hinder the applicability of the biomarkers. The objective of this study was to assess the adequacy of the application of biomarkers to evaluate psychological conditions among geriatric populations. METHOD: We collected information on the demographics and history of CVD in all participants. All participants completed the Brief Symptom Rating Scale (BSRS-5) and the Chinese Happiness Inventory (CHI), which are the measurement of negative and positive psychological conditions, respectively. Four indicators of the peripheral biomarkers, including the standard deviation of normal to normal RR intervals (SDNN), finger temperature, skin conductance, and electromyogram were collected for each participant during a 5-min resting state. Multiple linear regression models were conducted to evaluate the association between the biomarkers and the psychological measurements (BSRS-5, CHI) with and without the inclusion of the participants with CVD. RESULTS: A total of 233 participants without CVD (non-CVD group) and 283 participants with CVD (CVD group) were included. The CVD group was older and with higher body mass index compared to the non-CVD group. In the multiple linear regression model with all participants, only BSRS-5 scores had a positive association with electromyogram. After the exclusion of the CVD group, the association between the BSRS-5 scores and electromyogram was more relevant, while CHI scores became positively associated with SDNN. CONCLUSIONS: A single measurement of the peripheral biomarker may be insufficient to depict psychological conditions among geriatric populations.

Evaluation of the optimal cutoff number of types of social participation activities in older people.

INTRODUCTION: Social participation activities have a close association with health aging. However, the clinical significance of numbers of social participation activities and its cutoff value has not been defined. METHODS: We recruited 516 people aged ≥55 years. Twelve social participation behaviors modified according to Taiwanese culture were investigated, and the adequacy of cutoff number was determined by the area under the receiver operating characteristic curve (AUC) according to the results of cluster analysis of individual activities and scores of the Brief Symptom Rating Scale-5 (BSRS-5) and the Chinese Happiness Inventory (CHI). Demographic, BSRS-5 and CHI data were then compared according to the candidate cutoff numbers. RESULTS: The distribution of the numbers of social activities suggested that the highest partition of numbers of social activities was 3 in women and 4 in men. The AUC regarding the cluster of activity types was 0.917, with the highest Youden's J value located between 3 and 4. The AUC regarding the cluster of activity types and scores of the BSRS-5 and the CHI was 0.929, with similar cutoffs. If 3 and 4 were used as cutoffs, the between-group differences of both the CHI and the BSRS-5 were significant. More types of social activities had a different engaging frequency with the 3 and 4 cutoffs. CONCLUSION: Our findings found an adequate cutoff with better differential power in the psychopathology and happiness of older people that provided a basis for application in intervention and policy formation.

A Reverse Mutation E143K within the PrM Protein of Zika Virus Asian Lineage Natal RGN Strain Increases Infectivity and Cytopathicity.

Zika virus (ZIKV) is a positive-sense single-stranded RNA virus in the Flaviviridae, which is classified into two different lineages Asian and African. The outbreak of ZIKV Asian lineage isolates in 2015-2016 is associated with the increase in cases with prenatal microcephaly and Guillain-Barré syndrome, and has sparked attention throughout the world. Genome sequence alignment and the analysis of Asian and African lineage isolates indicate that amino acid changes, particular in positively charged amino acid substitutions in the pr region of prM protein might involve a phenotypic change that links with the global outbreak of ZIKV Asian-lineage. The study generated and characterized the virological properties of wild type and mutants of single-round infectious particles (SRIPs) and infectious clones (i.c.s) of ZIKV Asian-lineage Natal RGN strain, and then identified the function of amino acid substitutions at the positions 139 [Asn139→Ser139 (N139S)] and 143 [Glu143→Lys143 (E143K)] in ZIKV polyproteins (located within the pr region of prM protein) in the infectivity and cytopathogenicity. The E143K SRIP and i.c. of Natal RGN strain exhibited relatively higher levels of cytopathic effect, EGFP reporter, viral RNA and protein synthesis, and virus yield in three types of human cell lines, TE617, SF268 and HMC3, compared to wild type (WT), N139S SRIPs and i.c.s, which displayed more efficiency in replication kinetics. Additionally, E143K Natal RGN i.c. had greater activities of virus attachment and entry, yielded higher titers of intracellular and extracellular virions, and assembled the E proteins near to the plasma membrane in infected cells than the other i.c.s. The results indicate that the positively charged amino acid residue Lys143, a conserved residue in the pr region of prM of ZIKV African lineages, plays a crucial role in viral replication kinetics, including viral attachment, entry, assembly and egress. Thus, the negatively charged amino acid residue Glu143 within the pr region of prM leads to an alteration of the phenotypes, in particular, a lower replication efficiency of ZIKV Asian-lineage isolates with the attenuation of infectivity and cytopathicity.

Comparison between the analytical sensitivity and clinical performance of two cobas SARS-CoV-2 tests based on high-throughput and point-of-care systems.

Objectives: This study examined analytical sensitivity, specificity, and the clinical performance in detecting SARS-CoV-2 of the Cobas SARS-CoV-2 Test based on the high-throughput Cobas 6800 system and the Cobas SARS-CoV-2 & Flu A/B Test based on the point-of-care cobas Liat system. Methods: The commercial reagents containing SARS-CoV-2 RNA subgenomes were diluted for assessing the sensitivity of the RT-qPCR assay. 385 nasopharyngeal swab specimens taken from contacts of COVID-19 cases were tested for the SARS-CoV-2 detection with both Cobas SARS-CoV-2 Tests. Results: In analytical sensitivity assays, the Cobas SARS-CoV-2 & Flu A/B Test on the Liat system had a lower limit of detection (12.5-25 copies/mL) than the cobas SARS-CoV-2 Test on the cobas 6800 system (25-50 copies/mL). In clinical performance assays, the cobas SARS-CoV-2 Test demonstrated 89.36% (42 out of 47) PPA (positive percent agreement) and 98.82% (334 out of 338) NPA (negative percent agreement) compared to the results of the Cobas SARS-CoV-2 & Flu A/B test. Among five discordant specimens, four had the positive result of the cobas SARS-CoV-2 test, but the negative result of the cobas SARS-CoV-2 & Flu A/B Test. Moreover, these discordant specimens had the Ct values of greater than 33 for the cobas SARS-CoV-2 Test, implying a very small number of virions in the samples. Remarkably, four specimens with a presumptive positive result of the cobas SARS-CoV-2 test had been confirmed by the Cobas SARS-CoV-2 & Flu A/B Test. Next, the scatter plots of the Ct values showed a highly positive correlation between cobas SARS-CoV-2 & Flu A/B Test and the cobas SARS-CoV-2 Test (R-squared value = 0.954-0.962). Conclusions: Both SARS-CoV2 tests of the cobas 6800 and Liat systems produce reliable high throughput and point-of-care assays respectively for the early virus detection and the personal care decision-making during COVID-19 pandemic.

Haplotype distribution of SARS-CoV-2 variants in low and high vaccination rate countries during ongoing global COVID-19 pandemic in early 2021.

The widespread severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continuously impacts our economic and public health. The potential of emerging variants to increase transmissibility and evade vaccine-induced immunity lets us put more effort to research on viral mutations and explore the pathogenic haplotypes. In this study, we characterized the haplotype and sub-haplotype diversity of SARS-CoV-2 global variants in January-March and the areas with low and high COVID19 vaccination rates in May 2021 by analyzing viral proteome of complete genome sequences published. Phylogenetic tree analysis of the proteomes of SARS-CoV-2 variants with Neighbor-Joining and Maximum Parsimony methods indicated that haplotype 2 variant with nsp12 P323L and Spike D614G was dominant (98.81%), including new sub-haplotypes 2A_1 to 2A_3, 2B_1 to 2B_3, and 2C_1 to 2C_2 emerged post-one-year COVID-19 outbreak. In addition, the profiling of sub-haplotypes indicated that sub-haplotype 2A_1 with the mutations at N501Y, A570D, D614G, P681H, T716I, S982A, and D118H in Spike was over 58% in May 2021 in the high partly vaccinated rate group (US, Canada, and Germany). Meanwhile, the new haplotype 2C_3 bearing the mutations at EFR156-158del, T19R, A222V, L452R, T478K, and D614G in Spike occupied over 54.8% in May 2021 in the low partly vaccinated rate group (India, Malaysia, Taiwan, and Vietnam). Sub-haplotypes 2A_1 and 2C_3 had a meaningful alternation of ACE2-specific recognition site, neutralization epitopes, and furin cleavage site in SARS-CoV-2 Spike protein. The results discovered the haplotype diversity and new sub-haplotypes of SARS-CoV-2 variants post one-year pandemic in January-March 2021, showing the profiles of sub-haplotypes in the groups with low and high partly vaccinated rates in May 2021. The study reports the emergence of new SARS-CoV-2 sub-haplotypes during ongoing pandemic and vaccination in early 2021, which might help inform the response to vaccination strategies.

Effective Antiviral Activity of the Tyrosine Kinase Inhibitor Sunitinib Malate against Zika Virus.

INTRODUCTION: Zika virus (ZIKV), a mosquito-borne flavivirus, causes the outbreaks of Latin America in 2015 - 2016, with the incidence of neurological complications. Sunitinib malate, an orally bioavailable malate salt of the tyrosine kinase inhibitor, is suggested as a broad-spectrum antiviral agent against emerging viruses like severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. MATERIALS AND METHODS: This study investigated the antiviral efficacy and antiviral mechanisms of sunitinib malate against ZIKV infection using cytopathic effect reduction, virus yield, and time-of-addition assays. RESULTS: Sunitinib malate concentration-dependently reduced ZIKV-induced cytopathic effect, the expression of viral proteins, and ZIKV yield in supernatant with 50% inhibitory concentration (IC50) value of 0.015 µM, and the selectivity index of greater than 100 against ZIKV infection, respectively. Sunitinib malate had multiple antiviral actions during entry and post-entry stages of ZIKV replication. Sunitinib malate treatment at entry stage significantly reduced the levels of ZIKV RNA replication with the reduction of (+) RNA to (-) RNA ratio and the production of new intracellular infectious particles in infected cells. The treatment at post-entry stage caused a concentration-dependent increase in the levels of ZIKV (+) RNA and (-) RNA in infected cells, along with enlarging the ratio of (+) RNA to (-) RNA, but caused a pointed increase in the titer of intracellular infectious particles by 0.01 and 0.1 µM, and a substantial decrease in the titer of intracellular infectious particles by 1 µM. CONCLUSION: The study discovered the antiviral actions of sunitinib malate against ZIKV infection, demonstrating a repurposed, host-targeted approach to identify potential antiviral drugs for treating emerging and global viral diseases.

Synthesis and antiviral evaluation of cytisine derivatives against dengue virus types 1 and 2.

Dengue virus (DENV) causes about 50-100 million cases per year worldwide. However, there is still a big challenge in developing antiviral drugs against DENV infection. Some derivatives of alkaloid (-)-cytisine, like other alkaloid analogs, have been proposed for their antiviral potential. This study investigated antiviral activity and mechanisms of the cytisine derivatives, and discovered the structure-activity relationship against DENV. The antiviral assays were performed using one strain of DENV1 and DENV2, and two cell lines Vero E6 and A549. The structure-activity relationship of the effective compounds was also evaluated using combination of time-of-addition/removal assay and molecular docking. Compounds 3, 4, 12 (N-allylcytisine-3-thiocarbamide), 16, and 20 exhibited the high antiviral activity with IC50 values of lower than 3 µM against DENV1 and DENV2. Of them, the derivative 12 showed the highest antiviral activities against DENV1 (IC50 = 0.14 µM) and DENV-2 (IC50 = <0.1 µM), exhibiting the potent inhibition on virus attachment and entry stages. Meanwhile, the compounds 4 and 20 had a strong inhibition at the post-entry stage (IC50 = <0.1 µM). A correlation between the experimental pIC50 values and predicted pKi calculated by docking of compounds into DENV E protein was significant, correlating with the impact of compound 12 on the attachment stage, but compounds 4, and 20 on post-entry stage. The results provided the insight into the directions of synthetic modifications of starting (-)-cytisine as the inhibitors of DENV E protein at attachment and entry stages of DENV life cycle.

Glycyrrhetinic acid derivatives as Zika virus inhibitors: Synthesis and antiviral activity in vitro.

Zika virus (ZIKV) is an arbovirus of the Flaviviridae family (Flavivirus genus), causing serious neurological complications, such as Guillain-Barre Syndrome (GBS) in adults and fetal microcephaly. Licensed vaccines or specific antiviral agents against ZIKV do not currently exist. Therefore, the search and development of anti-ZIKV agents are particularly relevant and necessary. Glycyrrhetinic (3ß-hydroxy-11-oxo-18ßH-Olean-12-en-30-oic acid) (GA) 1 is one of the well-known pentacyclic triterpenoids isolated from licorice root (Glycyrrhiza glabra L., Gl. uralensis Fisher) (Leguminosae) possessing many biological features, including antiviral activity. This paper is devoted to the synthesis and studies of a number of nitrogen and sulfur-containing GA derivatives as ZIKV inhibitors. Sixteen GA and related triterpenoids (3ß-hydroxy-18ßH-Olean-12-en-30-oic acid and 3ß-hydroxy-11-oxo-18ßH-Olean-12(13),18(19)-dien-30-oic acid) derivatives were synthesized (amides, semi- and thiosemicarbazones, and 1,2,3-thiadiazoles) and antiviral activity against ZIKV was studied in vitro, including the inhibitory assays on cytopathic effect (CPE), viral protein synthesis, and replication stages. Four active compounds were found among GA derivatives tested, 13 (3-O-acetyl-30-aminopyridine GA), 16 (3-semicarbazone-30-butyl GA), 18 (1,2,3-thiadiazole-30-methyl GA), and 19 (1,2,3-thiadiazole-30-butyl GA) with IC50 < 1 µM against ZIKV replication. These compounds had a stronger inhibitory activity on ZIKV-induced CPE and viral protein translation in infected cells as compared to derivatives of 11-desoxo-GA. The most active compound was amide 13 (IC50 0.13 µM, TI ˃ 384). Time-of-addition assays indicated that 1,2,3-thiadiazole ring is important for inhibiting viral entry stage (compounds 18 and 19), while the 30-butyl ester group influenced on post-entry stage (compound 19). The molecular docking analysis demonstrated that lead compounds 13 and 19 forms a hydrogen-bond interaction with the catalytic triad (His51-Asp75-Ser135) of ZIKV NS2B-NS3 protease. Therefore, the active GA derivatives are promising for developing new antiviral agents against ZIKV infection.

The extent of molecular variation in novel SARS-CoV-2 after the six-month global spread.

The pandemic spread of Coronavirus Disease 2019 (COVID-19) is still ongoing since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is identified as the etiologic pathogen late December 2019. After over six-month spread of COVID-19, SARS-CoV-2 causes critical threats to global public health and economy. The investigations on evolution and genotyping on genetic variations are of great importance, therefore, the present study characterized the molecular variation of SARS-CoV-2 by analyzing 4230 complete genome sequences from the worldwide samples collected during the first 6-month pandemic. Phylogenetic tree analysis with Neighbor-Joining and Maximum-Parsimony methods indicated that the haplotypes of SARS-CoV-2 genome sequences were classified into four clades with the unique nucleotide and amino acid changes: T27879C (ORF8 L84S) in clade 1 (25.34%), A23138G (spike D614G) in clade 2 (63.54%), G10818T (nsp6 L37F), C14540T (nsp12 T442I), and G25879T (ORF3a V251F) in clade 3 (2.58%), and miscellaneous changes in clade 4 (8.54%). Interestingly, subclade 2B with the amino acid changes at nsp2 T85I, Spike D614G, and ORF3a Q57H was firstly reported on March 4, 2020 in United States of America, becoming the most frequent sub-haplogroup in the world (36.21%) and America (45.81%). Subclade 1C with the amino acid changes at nsp13 P504L and ORF8 L84S was becoming the second most frequent sub-haplogroup in the world (19.91%) and America (26.29%). Subclade 2A with the amino acid changes in Spike D614G and Nucleocapsid R203K and G204R was highly prevalent in Asia (18.82%) and Europe (29.72%). The study highlights the notable clades and sub-clades with unique mutations, revealing the genetic and geographical relevant post the six-month outbreak of COVID-19. This study thoroughly observed the genetic feature of SARS-CoV-2 haplotyping, providing an epidemiological trend of COVID-19.

Antiviral activity of glycyrrhizic acid conjugates with amino acid esters against Zika virus.

Zika virus (ZIKV) is a new pathogenic flavivirus transmitted by mosquitoes Aedes spp. ZIKV infection is accompanied by serious neurological complications and is especially dangerous for pregnant women, in which it can lead to congenital malformations of the fetus and microcephaly in neonates. Currently, there are no licensed vaccines or specific post-infectious therapies for ZIKV infection. This report is devoted to the study of glycyrrhizic acid (GL) derivatives as ZIKV inhibitors. The inhibitory assays on the cytopathic effect (CPE) and viral infectivity of ZIKV in three different human cell lines revealed that the conjugation of GL with amino acids and their esters (methyl, ethyl) is influenced by the antiviral activity of the compounds. GL conjugates with Glu(OMe)-OMe 11, Glu(OH)-OMe 12, Asp(OMe)-OMe 13, TyrOMe 14, LeuOEt 15, and PheOEt 16 with free COOH groups in the triterpene moiety were active against ZIKV. The most active compounds 13 and 14 have IC50 values of 0.23 µM and 0.09 µM against low doses (MOI = 0.05) of ZIKV strain PRVABC59, 1.20 µM and 0.74 µM against high doses (MOI = 10) of ZIKV strain Natal RGN single-round infectious particles, respectively. The lead compound was 14 with a high selectivity index (SI < 500). Compound 13 showed a higher inhibitory effect on the early stage (entry) of ZIKV replication than compound 14, and was less potent than compound 14 at the post-entry stage, consistent with the docking models. Compounds 13 and 14 also had a strong interaction with the active site pocket of NS5 MTase. Compounds 13 and 14 are recommended for expanded antiviral studies against ZIKV infection.

Mobile Health App With Social Media to Support Self-Management for Patients With Chronic Kidney Disease: Prospective Randomized Controlled Study.

BACKGROUND: Chronic kidney disease (CKD) is a global health burden. Self-management plays a key role in improving modifiable risk factors. OBJECTIVE: The aim of this study was to evaluate the effectiveness of wearable devices, a health management platform, and social media at improving the self-management of CKD, with the goal of establishing a new self-management intervention model. METHODS: In a 90-day prospective experimental study, a total of 60 people with CKD at stages 1-4 were enrolled in the intervention group (n=30) and control group (n=30). All participants were provided with wearable devices that collected exercise-related data. All participants maintained dietary diaries using a smartphone app. All dietary and exercise information was then uploaded to a health management platform. Suggestions about diet and exercise were provided to the intervention group only, and a social media group was created to inspire the participants in the intervention group. Participants' self-efficacy and self-management questionnaire scores, Kidney Disease Quality of Life scores, body composition, and laboratory examinations before and after the intervention were compared between the intervention and control groups. RESULTS: A total of 49 participants completed the study (25 in the intervention group and 24 in the control group); 74% of the participants were men and the mean age was 51.22 years. There were no differences in measured baseline characteristics between the groups except for educational background. After the intervention, the intervention group showed significantly higher scores for self-efficacy (mean 171.28, SD 22.92 vs mean 142.21, SD 26.36; P<.001) and self-management (mean 54.16, SD 6.71 vs mean 47.58, SD 6.42; P=.001). Kidney Disease Quality of Life scores were also higher in the intervention group (mean 293.16, SD 34.21 vs mean 276.37, SD 32.21; P=.02). The number of steps per day increased in the intervention group (9768.56 in week 1 and 11,389.12 in week 12). The estimated glomerular filtration rate (eGFR) of the intervention group was higher than that of the control group (mean 72.47, SD 24.28 vs mean 59.69, SD 22.25 mL/min/1.73m2; P=.03) and the decline in eGFR was significantly slower in the intervention group (-0.56 vs -4.58 mL/min/1.73m2). There were no differences in body composition between groups postintervention. CONCLUSIONS: The use of wearable devices, a health management platform, and social media support not only strengthened self-efficacy and self-management but also improved quality of life and a slower eGFR decline in people with CKD at stages 1-4. These results outline a new self-management model to promote healthy lifestyle behaviors for patients with CKD. TRIAL REGISTRATION: ClinicalTrials.gov NCT04617431; https://www.clinicaltrials.gov/ct2/show/NCT04617431.

Protective effects of luteolin against oxidative stress and mitochondrial dysfunction in endothelial cells.

BACKGROUND AND AIMS: Luteolin is a common flavonoid that is abundantly present in various edible plants, it is known to exhibit beneficial effects on cardiovascular system. However, the mechanisms which underlie the protective effects of luteolin on endothelial cell damage caused by oxidative stress remains unclear. The purpose of this study is to test the hypothesis which states that luteolin protects against H2O2-induced oxidative stress via modulating ROS-mediated P38 MAPK/NF-κB and calcium-evoked mitochondrial apoptotic signalling pathways. METHODS AND RESULTS: Human umbilical vein endothelial cells (HUVECs) were pretreated with luteolin prior to being stimulated by 600 µM H2O2 for another 24 h. The expression of native and phosphorylated-P38, IκB, NF-κB, native eNOS, phosphorylated-eNOS, iNOS and several apoptosis-related proteins were analyzed by Western blot. In addition, intracellular calcium was determined by fura-2 AM and mitochondrial membrane potential was examined by using JC1. Using the data gathered, we found indications that H2O2 induced P38 MAPK/NF-κB activation. H2O2 downregulated the expression of eNOS and upregulated iNOS, which in turn contribute to an elevated NO generation and protein nitrosylation. However, pretreatment with luteolin markedly reversed all of these alterations dose-dependently. Additionally, an intracellular calcium rise and subsequent mitochondrial membrane potential collapse, P53 phosphorylation, reduced BcL-2/Bax ratio in the mitochondrial membrane, release cytochrome c from mitochondria, leading to the subsequent activation of caspase 3 activation by H2O2 were all markedly suppressed in the presence of luteolin. CONCLUSION: Results from this study may provide the possible molecular mechanisms underlying cardiovascular protective effects of luteolin.

SARS Unique Domain (SUD) of Severe Acute Respiratory Syndrome Coronavirus Induces NLRP3 Inflammasome-Dependent CXCL10-Mediated Pulmonary Inflammation.

Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) initiates the cytokine/chemokine storm-mediated lung injury. The SARS-CoV unique domain (SUD) with three macrodomains (N, M, and C), showing the G-quadruplex binding activity, was examined the possible role in SARS pathogenesis in this study. The chemokine profile analysis indicated that SARS-CoV SUD significantly up-regulated the expression of CXCL10, CCL5 and interleukin (IL)-1ß in human lung epithelial cells and in the lung tissues of the mice intratracheally instilled with the recombinant plasmids. Among the SUD subdomains, SUD-MC substantially activated AP-1-mediated CXCL10 expression in vitro. In the wild type mice, SARS-CoV SUD-MC triggered the pulmonary infiltration of macrophages and monocytes, inducing CXCL10-mediated inflammatory responses and severe diffuse alveolar damage symptoms. Moreover, SUD-MC actuated NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome-dependent pulmonary inflammation, as confirmed by the NLRP3 inflammasome inhibitor and the NLRP3-/- mouse model. This study demonstrated that SARS-CoV SUD modulated NLRP3 inflammasome-dependent CXCL10-mediated pulmonary inflammation, providing the potential therapeutic targets for developing the antiviral agents.

Antiviral Action of Tryptanthrin Isolated from Strobilanthes cusia Leaf against Human Coronavirus NL63.

Strobilanthes cusia (Nees) Kuntze is a Chinese herbal medicine used in the treatment of respiratory virus infections. The methanol extract of S. cusia leaf contains chemical components such as ß-sitosterol, indirubin, tryptanthrin, betulin, indigodole A, and indigodole B that have diverse biological activities. However, the antiviral action of S. cusia leaf and its components against human coronavirus remains to be elucidated. Human coronavirus NL63 infection is frequent among immunocompromised individuals, young children, and in the elderly. This study investigated the anti-Human coronavirus NL63 (HCoV-NL63) activity of the methanol extract of S. cusia leaf and its major components. The methanol extract of S. cusia leaf effectively inhibited the cytopathic effect (CPE) and virus yield (IC50 = 0.64 µg/mL) in HCoV-NL63-infected cells. Moreover, this extract potently inhibited the HCoV-NL63 infection in a concentration-dependent manner. Among the six components identified in the methanol extract of S. cusia leaf, tryptanthrin and indigodole B (5aR-ethyltryptanthrin) exhibited potent antiviral activity in reducing the CPE and progeny virus production. The IC50 values against virus yield were 1.52 µM and 2.60 µM for tryptanthrin and indigodole B, respectively. Different modes of time-of-addition/removal assay indicated that tryptanthrin prevented the early and late stages of HCoV-NL63 replication, particularly by blocking viral RNA genome synthesis and papain-like protease 2 activity. Notably, tryptanthrin (IC50 = 0.06 µM) and indigodole B (IC50 = 2.09 µM) exhibited strong virucidal activity as well. This study identified tryptanthrin as the key active component of S. cusia leaf methanol extract that acted against HCoV-NL63 in a cell-type independent manner. The results specify that tryptanthrin possesses antiviral potential against HCoV-NL63 infection.

The Rescue and Characterization of Recombinant, Microcephaly-Associated Zika Viruses as Single-Round Infectious Particles.

Zika virus (ZIKV) is transmitted by Aedes mosquitoes and exhibits genetic variation with African and Asian lineages. ZIKV Natal RGN strain, an Asian-lineage virus, has been identified in brain tissues from fetal autopsy cases with microcephaly and is suggested to be a neurotropic variant. However, ZIKV Natal RGN strain has not been isolated; its biological features are not yet illustrated. This study rescued and characterized recombinant, single-round infectious particles (SRIPs) of the ZIKV Natal RGN strain using reverse genetic and synthetic biology techniques. The DNA-launched replicon of ZIKV Natal RGN was constructed and contains the EGFP reporter, lacks prM-E genes, and replicates under CMV promoter control. The peak in the ZIKV Natal RGN SRIP titer reached 6.25 × 106 TCID50/mL in the supernatant of prM-E-expressing packaging cells 72 h post-transfection with a ZIKV Natal RGN replicon. The infectivity of ZIKV Natal RGN SRIPs has been demonstrated to correlate with the green florescence intensity of the EGFP reporter, the SRIP-induced cytopathic effect, and ZIKV's non-structural protein expression. Moreover, ZIKV Natal RGN SRIPs effectively self-replicated in rhabdomyosarcoma/muscle, glioblastoma/astrocytoma, and retinal pigmented epithelial cells, displaying unique cell susceptibility with differential attachment activity. Therefore, the recombinant ZIKV Natal RGN strain was rescued as SRIPs that could be used to elucidate the biological features of a neurotropic strain regarding cell tropism and pathogenic components, apply for antiviral agent screening, and develop vaccine candidates.

Antiviral efficacy of bromo-anilino substituents of 4,5-dihydrofuran-3-carboxylate compound CW-33 against Japanese encephalitis virus.

Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, occasionally causes severe central nervous system disorders in the risk zone where more than 3 billion people reside. Our prior studies demonstrated antiviral potential of 4,5-dihydrofuran-3-carboxylate compound CW-33 (ethyl 2-(3',5'-dimethylanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) and its derivative CW-33A ((ethyl 2-(2-fluoroanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) against JEV infection ((Int. J. Mol. Sci. 2016, 17: E1386; Sci. Rep. 2018, 8: 16595). This study synthesized six new CW-33 derivatives containing chloro, or bromo groups at the C-2, C-3, or C-4 of anilino ring of CW-33, and assessed the antiviral activity and mechanisms of these chloro- and bromo-anilino substitutedderivatives. CW-33K, CW-33L and CW-33M had the bromo-substituents at the C-2, C-3, or C-4 of anilino ring of CW-33, respectively, showing the higher anti-JEV activity than CW-33 and other derivatives. CW-33K (ethyl 2-(2-bromoanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) exhibited the highest antiviral efficacy and therapeutic index. The IC50 value of CW-33K was less than 5 µM for reducing JEV-induced cytopathic effect, virus infectivity and virus yield. CW-33K significantly inhibited the JEV replication at the early and late stages, suppressing viral RNA synthesis and intracellular JEV particle production. The study demonstrated that the CW-33 derivative with a bromosubstitutionat the C-2 anilino ring improved the antiviral activity JEV, providing the structure-antiviral activity relationship for the development of anti-JEV agents.

Antiviral activity of Sambucus FormosanaNakai ethanol extract and related phenolic acid constituents against human coronavirus NL63.

Human coronavirus NL63 (HCoV-NL63), one of the main circulating HCoVs worldwide, causes respiratory tract illnesses like runny nose, cough, bronchiolitis and pneumonia. Recently, a severe respiratory illness outbreak of HCoV-NL63 has been reported in a long-term care facility. Sambucus FormosanaNakai, a species of elderberry, is a traditional medicinal herb with anti-inflammatory and antiviral potential. The study investigated the antiviral activity of Sambucus FormosanaNakai stem ethanol extract and some phenolic acid constituents against HCoV-NL63. The extract was less cytotoxic and concentration-dependently increased anti-HCoV-NL63 activities, including cytopathicity, sub-G1 fraction, virus yield (IC50 = 1.17 µg/ml), plaque formation (IC50 = 4.67 µg/ml) and virus attachment (IC50 = 15.75 µg/ml). Among the phenolic acid constituents in Sambucus FormosanaNakai extract, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity that was ranked in the following order of virus yield reduction: caffeic acid (IC50 = 3.54 µM) > chlorogenic acid (IC50 = 43.45 µM) > coumaric acid (IC50 = 71.48 µM). Caffeic acid significantly inhibited the replication of HCoV-NL63 in a cell-type independent manner, and specifically blocked virus attachment (IC50 = 8.1 µM). Therefore, the results revealed that Sambucus Formosana Nakai stem ethanol extract displayed the strong anti-HCoV-NL63 potential; caffeic acid could be the vital component with anti-HCoV-NL63 activity. The finding could be helpful for developing antivirals against HCoV-NL63.

Glycyrrhizic acid derivatives as Dengue virus inhibitors.

Dengue virus (DENV) is one of the most geographically distributed pathogenic flaviviruses transmitted by mosquitoes Aedes sps. In this study, the structure-antiviral activity relationships of Glycyrrhizic acid (GL) derivatives was evaluated by the inhibitory assays on the cytopathic effect (CPE) and viral infectivity of DENV type 2 (DENV2) in Vero E6 cells. GL (96% purity) had a low cytotoxicity to Vero E6 cells, inhibited DENV2-induced CPE, and reduced the DENV-2 infectivity with the IC50 of 8.1 µM. Conjugation of GL with amino acids or their methyl esters and the introduction of aromatic acylhydrazide residues into the carbohydrate part strongly influenced on the antiviral activity. Among compounds tested GL conjugates with isoleucine 13 and 11-aminoundecanoic acid 17 were found as potent anti-DENV2 inhibitors (IC50 1.2-1.3 µM). Therefore, modification of GL is a perspective way in the search of new antivirals against DENV2 infection.