Lipopeptide-Based Nanosome-Mediated Delivery of Hyperaccurate CRISPR/Cas9 Ribonucleoprotein for Gene Editing.

A transient cytosolic delivery system for accurate Cas9 ribonucleoprotein is a key factor for target specificity of the CRIPSR/Cas9 toolkit. Owing to the large size of the Cas9 protein and a long negative strand RNA, the development of the delivery system is still a major challenge. Here, a size-controlled lipopeptide-based nanosome system is reported, derived from the blood-brain barrier-permeable dNP2 peptide which is capable of delivering a hyperaccurate Cas9 ribonucleoprotein complex (HypaRNP) into human cells for gene editing. Each nanosome is capable of encapsulating and delivering ≈2 HypaRNP molecules into the cytoplasm, followed by nuclear localization at 4 h post-treatment without significant cytotoxicity. The HypaRNP thus efficiently enacts endogenous eGFP silencing and editing in human embryonic kidney cells (up to 27.6%) and glioblastoma (up to 19.7% frequency of modification). The lipopeptide-based nanosome system shows superior delivery efficiency, high controllability, and simplicity, thus providing biocompatibility and versatile platform approach for CRISPR-mediated transient gene editing applications.

Structure-Guided Engineering of Thermodynamically Enhanced SaCas9 for Improved Gene Suppression.

Proteins with multiple domains play pivotal roles in various biological processes, necessitating a thorough understanding of their structural stability and functional interplay. Here, a structure-guided protein engineering approach is proposed to develop thermostable Cas9 (CRISPR-associated protein 9) variant for CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) interference applications. By employing thermodynamic analysis, combining distance mapping and molecular dynamics simulations, deletable domains are identified to enhance stability while preserving the DNA recognition function of Cas9. The resulting engineered Cas9, termed small and dead form Cas9, exhibits improved thermostability and maintains target DNA recognition function. Cryo-electron microscopy analysis reveals structural integrity with reduced atomic density in the deleted domain. Fusion with functional elements enables intracellular delivery and nuclear localization, demonstrating efficient gene suppression in diverse cell types. Direct delivery in the mouse brain shows enhanced knockdown efficiency, highlighting the potential of structure-guided engineering to develop functional CRISPR systems tailored for specific applications. This study underscores the significance of integrating computational and experimental approaches for protein engineering, offering insights into designing tailored molecular tools for precise biological interventions.

Peptide-Drug Conjugate with Statistically Designed Transcellular Peptide for Psoriasis-Like Inflammation.

Peptide-drug conjugates (PDCs) are a promising class of drug delivery systems that utilize covalently conjugated carrier peptides with therapeutic agents. PDCs offer several advantages over traditional drug delivery systems including enhanced target engagement, improved bioavailability, and increased cell permeability. However, the development of efficient transcellular peptides capable of effectively transporting drugs across biological barriers remains an unmet need. In this study, physicochemical criteria based on cell-penetrating peptides are employed to design transcellular peptides derived from an antimicrobial peptides library. Among the statistically designed transcellular peptides (SDTs), SDT7 exhibits higher skin permeability, faster kinetics, and improved cell permeability in human keratinocyte cells compared to the control peptide. Subsequently, it is found that 6-Paradol (PAR) exhibits inhibitory activity against phosphodiesterase 4, which can be utilized for an anti-inflammatory PDC. The transcellular PDC (SDT7-conjugated with PAR, named TM5) is evaluated in mouse models of psoriasis, exhibiting superior therapeutic efficacy compared to PAR alone. These findings highlight the potential of transcellular PDCs (TDCs) as a promising approach for the treatment of inflammatory skin disorders.

A genome-wide association study of a coronary artery disease risk variant.

Although over 30 common genetic susceptibility loci have been identified to be independently associated with coronary artery disease (CAD) risk through genome-wide association studies (GWAS), genetic risk variants reported to date explain only a small fraction of heritability. To identify novel susceptibility variants for CAD and confirm those previously identified in European population, GWAS and a replication study were performed in the Koreans and Japanese. In the discovery stage, we genotyped 2123 cases and 3591 controls with 521 786 SNPs using the Affymetrix SNP Array 6.0 chips in Korean. In the replication, direct genotyping was performed using 3052 cases and 4976 controls from the KItaNagoya Genome study of Japan with 14 selected SNPs. To maximize the coverage of the genome, imputation was performed based on 1000 Genome JPT+CHB and 5.1 million SNPs were retained. CAD association was replicated for three GWAS-identified loci (1p13.3/SORT1 (rs599839), 9p21.3/CDKN2A/2B (rs4977574), and 11q22.3/ PDGFD (rs974819)) in Koreans. From GWAS and a replication, SNP rs3782889 showed a strong association (combined P=3.95 × 10(-14)), although the association of SNP rs3782889 doesn't remain statistically significant after adjusting for SNP rs11066015 (proxy SNP with BRAP (r(2)=1)). But new possible CAD-associated variant was observed for rs9508025 (FLT1), even though its statistical significance did marginally reach at the genome-wide a significance level (combined P=6.07 × 10(-7)). This study shows that three CAD susceptibility loci, which were previously identified in European can be directly replicated in Koreans and also provides additional evidences implicating suggestive loci as risk variants for CAD in East Asian.

Mechanistic insights into the anti-restenotic effects of HSP27 and HO1 modulated by reconstituted HDL on neointimal hyperplasia.

High-density lipoprotein (HDL) therapy has demonstrated beneficial effects in acute stroke and acute myocardial infarction models by reducing infarct size. In this study, we investigated the inhibitory effects of reconstituted HDL (rHDL) on neointimal hyperplasia and elucidated its underlying mechanism using a balloon injury rat model. Our finding revealed a significant 37% reduction in the intima to media ratio in the arteries treated with 80 mg/kg rHDL compared to those subjected to injury alone (p < 0.05), indicating a specific inhibition of neointimal hyperplasia. In vivo analysis further supported the positive effects of rHDL by demonstrating a reduction in smooth muscle cell (SMC) proliferation and an increase in endothelial cell (EC) proliferation. Additionally, rHDL treatment led to decreased infiltration of leukocytes and downregulated the expression of matrix metallopeptidase 9 (MMP9) in the neointimal area. Notably, rHDL administration resulted in decreased expression of VCAM1 and HIF1α, alongside increased expression of heme oxygenase 1 (HO1) and heat shock protein 27 (HSP27). Overexpression of HSP27 and HO1 effectively inhibited SMC proliferation. Moreover, rHDL-mediated suppression of injury-induced HIF1α coincided with upregulation of HSP27. Interestingly, HSP27 and HO1 had varying effects on the expression of chemokine receptors and rHDL did not exert significant effect on chemokine receptor expression in THP1 cells. These findings underscore the distinct roles of HSP27 and HO1 as potential regulatory factors in the progression of restenosis. Collectively, our study demonstrates that rHDL exerts a potent anti-neointimal hyperplasia effect by reducing leukocytes infiltration and SMC proliferation while promoting EC proliferation.

Multiplex coherent anti-stokes Raman spectroscopy images intact atheromatous lesions and concomitantly identifies distinct chemical profiles of atherosclerotic lipids.

RATIONALE: Lipids are a key component of atherogenesis. However, their physiological role on the progression of atherosclerosis including plaque vulnerability has not been clearly understood, because of the lack of appropriate tools for chemical assessment. OBJECTIVE: We aimed to develop a label-free chemical imaging platform based on multiplex coherent anti-Stokes Raman scattering (CARS) for the correlative study of the morphology and chemical profile of atherosclerotic lipids. METHODS AND RESULTS: Whole aortas from atherosclerotic apolipoprotein E knock-out mice were en face examined by multiplex CARS imaging and 4 distinctive morphologies of the lipids (intra/extracellular lipid droplets and needle-/plate-shaped lipid crystals) were classified. The chemical profiles of atherosclerotic lipids depending on morphologies were firstly identified from intact atheromatous tissue by multiplex CARS. We demonstrated that needle-/plate-shaped lipid crystals in advanced plaques had undergone a phase shift to the solid state with increased protein contents, implying that lipid modification had occurred beforehand. The validity of lipid-selective multiplex CARS imaging was supported by comparative results from oil red O staining and whole-mount immunohistochemistry. By spatial CARS analysis of atherosclerosis progression, we found greater accumulation of lipid crystals in both the lesser curvature of the aortic arch and the innominate artery. Furthermore, multiplex CARS measurement successfully demonstrated the effect of a drug, statin, on atherosclerotic lipids by showing the change of their chemical profiles. CONCLUSIONS: Multiplex CARS imaging directly provides intact morphologies of atherosclerotic lipids with correlative chemical information, thereby suggesting its potential applications in the investigation of lipid-associated disorders and the preclinical drug screening.

Inhibition of T cell receptor signal transduction by tyrosine kinase-interacting protein of Herpesvirus saimiri.

T cells play a central role in orchestrating immunity against pathogens, particularly viruses. Thus, impairing T cell activation is an important strategy employed by viruses to escape host immune control. The tyrosine kinase-interacting protein (Tip) of the T lymphotropic Herpesvirus saimiri (HVS) is constitutively present in lipid rafts and interacts with cellular Lck tyrosine kinase and p80 endosomal protein. Here we demonstrate that, due to the sequestration of Lck by HVS Tip, T cell receptor (TCR) stimulation fails to activate ZAP70 tyrosine kinase and to initiate downstream signaling events. TCR zeta chains in Tip-expressing T cells were initially phosphorylated to recruit ZAP70 molecule upon TCR stimulation, but the recruited ZAP70 kinase was not subsequently phosphorylated, resulting in TCR complexes that were stably associated with inactive ZAP70 kinase. Consequently, Tip expression not only markedly inhibited TCR-mediated intracellular signal transduction but also blocked TCR engagement with major histocompatibility complexes on the antigen-presenting cells and immunological synapse formation. These results demonstrate that a lymphotropic herpesvirus has evolved a novel mechanism to deregulate T cell activation to disarm host immune surveillance. This process contributes to the establishment and maintenance of viral latency.

Megakaryoblastic leukemia factor-1 gene in the susceptibility to coronary artery disease.

Coronary artery disease (CAD) is based on the atherosclerosis of coronary artery and may manifest with myocardial infarction or angina pectoris. Although it is widely accepted that genetic factors are linked to CAD and several disease-related genes have been reported, only a few could be replicated suggesting that there might be some other CAD-related genes. To identify novel susceptibility loci for CAD, we used microsatellite markers in the screening and found six different candidate CAD loci. Subsequent single nucleotide polymorphism (SNP) association studies revealed an association between CAD and megakaryoblastic leukemia factor-1 gene (MKL1). The association with a promoter SNP of MKL1, -184C > T, was found in a Japanese population and the association was replicated in another Japanese population and a Korean population. Functional analysis of the MKL1 promoter SNP suggested that the higher MKL1 expression was associated with CAD. These findings suggest that MKL1 is involved in the pathogenesis of CAD.

Replication studies for the association of PSMA6 polymorphism with coronary artery disease in East Asian populations.

Coronary artery disease (CAD) has become a major health problem in many countries because of its increasing prevalence and high mortality. Recently, an association of a functional sequence variation, -8C>G, in the human proteasome subunit alpha type 6 gene (PSMA6) with the susceptibility to CAD was reported. To validate the association, we investigated a total of 1330 cases and 2554 controls from Japanese and Korean populations for PSMA6 genotypes, and no evidence of the association was obtained in both Japanese (odds ratio (OR)=1.03, 95% confidence interval (CI); 0.90-1.19, P=0.66, allele count model) and Korean populations (OR=1.00, 95% CI; 0.86-1.17, P=0.95, allele count model). However, when a meta-analysis of data from this study and previously reported six replication studies was done, OR was 1.08 for the G allele (95% CI; 1.02-1.14, P=0.0057), suggesting that the contribution of PSMA6 to CAD was not large enough to be readily replicated. Further studies are required to establish the contribution of this variant in the susceptibility to CAD.

Validation of eight genetic risk factors in East Asian populations replicated the association of BRAP with coronary artery disease.

Coronary artery disease (CAD) is caused by a thrombotic occlusion or spasm of the coronary artery. Association of genetic variants with susceptibility to CAD has been reported in various populations, but the association should be replicated in other populations to establish the role of genetic variants in CAD. We conducted a case-control study with a total of 1480 CAD cases and 2115 controls from two East Asian populations, Japanese and Korean, to validate the associations of CAD with eight single nucleotide polymorphisms (SNPs) in eight loci, which were identified from large-scale whole-genome association studies in Europeans or East Asians. Among the tested SNPs, one SNP in BRAP (rs11066001) showed a significant association in allele frequency distribution with CAD in both the Japanese (Odds ratio (OR)=1.63, 95% confidence interval (CI); 1.41-1.89, P=5.0 x 10(-11), corrected P (Pc)=4.0 x 10(-10)) and Korean populations (OR=1.68, 95% CI; 1.41-2.00, P=6.5 x 10(-9), Pc=5.2 x 10(-9)), and a meta-analysis showed a significant association in the East Asian populations (OR=1.65, 95% CI; 1.48-1.85, P=1.8 x 10(-18), Pc=1.4 x 10(-17)), whereas no evidence of association was found for the other SNPs. In addition, a combined analysis of BRAP and another CAD locus on 9p21 suggested that these loci had a synergistic role in the susceptibility. Failure to replicate the association with the other SNPs, which were reported in the European populations, suggested that their contributions to CAD were not large enough to be readily captured in the East Asian populations.

Validation of the association between AGTRL1 polymorphism and coronary artery disease in the Japanese and Korean populations.

Coronary artery disease (CAD) and stroke are the major health problems in many countries because of their increasing prevalence and high mortality. It is well known that CAD and stroke are based on atherosclerosis and shared environmental and genetic risk factors. Recently, an association of a functional sequence variation -154G>A in the angiotensin receptor-like 1 (AGTRL1) with a susceptibility to stroke was reported. In this study, we investigated a total of 1479 CAD cases and 2062 controls from the Japanese and Korean populations to validate the association of AGTRL1 with CAD. However, we obtained no evidence of the association in both the Japanese (odds ratio (OR)=0.95, 95% confidence interval (CI); 0.82-1.10, P=0.47, allele count model) and Korean (OR=0.90, 95% CI; 0.77-1.05, P=0.18, allele count model) populations. In addition, there was no trend of association between the risk allele and severity of coronary atherosclerosis. These data suggested that AGTRL1 did not contribute much to the atherosclerosis of the coronary artery.

Four SNPs on chromosome 9p21 in a South Korean population implicate a genetic locus that confers high cross-race risk for development of coronary artery disease.

OBJECTIVE: Recent genome-wide association studies have identified 4 SNPs on chromosome 9p21 associated with CAD (rs10757274 and rs2383206) and myocardial infarction (MI: rs2383207 and rs10757278) in White populations in Northern Europe and North America. We aimed to determine whether this locus confers significant susceptibility to CAD in a South Korean population, and thus cross-race susceptibility to CAD. METHODS AND RESULTS: We performed a case-control association study with 611 unrelated CAD patients and 294 normal controls from South Korea. Allelic associations of SNPs and SNP haplotypes with CAD were evaluated. Multivariate logistic regression analysis was used to adjust effects of clinical covariates. We found that 4 SNPs on chromosome 9p21 were associated with susceptibility to CAD in a South Korean population. The association remained significant after adjusting for significant clinical covariates (P=0.001 to 0.024). We identified one risk haplotype (GGGG; P=0.017) and one protective haplotype (AAAA; P=0.007) for development of CAD. Further analysis suggested that the SNPs probably confer susceptibility to CAD in a dominance model (covariates-adjusted P=0.001 to 0.024; OR=2.37 to 1.54). This represents the first study that expands association of these 9p21 SNPs with CAD beyond White populations. CONCLUSIONS: Chromosome 9p21 is an important susceptibility locus that confers high cross-race risk for development of CAD.

Distinct role of IL-3 promoter and enhancer region in murine mast cells.

Crosslinking of Fcvarepsilon receptor on mast cells induces IL-3 gene expression with the concentration dependent of intracellular calcium, but its regulatory mechanism remains unclear. Here, we found that phorbol 12-myristate 13-acetate (PMA) alone did not induce IL-3 gene expression, but potentiated A23187-induced IL-3 gene expression. Interestingly, the A23187-induced IL-3 promoter activity was suppressed by PMA, but it was enhanced when IL-3 promoter contained enhancer region, a DH site. While IL-3 mRNA expression was increased by A23187 and PMA in a dose-dependent manner, the promoter activity appeared all or none in all doses of A23187 and PMA. IL-3 promoter region between -293 and -150bp was responsible for A23187-induced gene expression and PMA- or cyclosporin A (CsA)-mediated suppression. Taken together, IL-3 gene expression was primarily regulated at the transcriptional level, which was differentially controlled by a restricted promoter and enhancer region.

Wogonin suppresses TARC expression induced by mite antigen via heme oxygenase 1 in human keratinocytes. Suppressive effect of wogonin on mite antigen-induced TARC expression.

BACKGROUND: Mite antigen, extract from Dermatophagoides farinae in house dust, is a well-known causative agent of atopy or allergic diseases, which involves many inflammatory cytokines/chemokines expression. Heme oxygenase 1 (HO1) has recently emerged as an important cytoprotective enzyme against oxidative stress and inflammatory responses in many cell types. OBJECTIVE: The aim of this study was to investigate the possible mechanism by which wogonin, a natural product isolated from Scutellaria baicalensis, inhibited the mite antigen-induced chemokine expression in human keratinocytes, HaCaT cells. METHODS: The level of chemokine expression was measured by reverse transcription-polymerase chain reaction (RT-PCR) and signaling study was performed by Western blot analysis. RESULTS: The mite antigen-induced thymus- and activation-regulated chemokine (TARC/CCL17) expression in a dose-dependent manner via extracellular signal-regulated kinase (ERK) activation. However, it did not affect the expression of other chemokines including macrophage-derived chemokine (MDC/CCL22), RANTES, and IL-8. Interestingly, wogonin significantly suppressed the mite antigen-induced TARC expression via the induction of HO1. This suppression was completely restored by HO1 siRNA, suggesting a direct role of HO1 for the suppressive effect. Furthermore, exogenous CO, but not other end products of HO1 activity, also suppressed the mite antigen-induced TARC expression. CONCLUSION: Wogonin induces HO1 expression, which in turn HO1 and/or CO suppresses TARC expression induced by mite antigen in human HaCaT cells.

HMCO5, herbal extract, inhibits NF-kappaB expression in lipopolysaccharide treated macrophages and reduces atherosclerotic lesions in cholesterol fed mice.

HMCO5 is a herbal extract which comprises of eight different herbs. We studied whether this extract has anti-atherosclerotic effects. In lipopolysaccharide (LPS) stimulated RAW264.7 cells, HMCO5 inhibited NF-kappaB activation as well as iNOS promoter activity, inhibited the secretion of TNF-alpha and IL-1beta, and directly inhibited the intracellular accumulation of reactive oxygen species. ApoE knock-out mice fed a high-fat high-cholesterol diet with HMCO5 for 10 weeks showed a significant reduction in atherosclerotic lesions. A notable finding was the preservation of the smooth muscle cell layer in the media of aorta in the HMCO5 co-treated mice. HMCO5 treated mice did not show significant decrease in serum level of cholesterol. These results suggest that HMCO5 has anti-atherosclerotic effects which in part may be attributable to the inhibition of production of NF-kappaB dependent pro-inflammatory cytokines.

Genome-based exome sequencing analysis identifies GYG1, DIS3L and DDRGK1 are associated with myocardial infarction in Koreans.

Myocardial infarction (MI) is a complex disease caused by combination of genetic and environmental factors. Although genome-wide association studies (GWAS) identified more than 46 risk loci which are associated with coronary artery disease and MI, most of the genetic variability inMI still remains undefined. Here, we screened the susceptibility loci for MI using exome sequencing and validated candidate variants in replication sets. We identified that three genes (GYG1, DIS3L and DDRGK1) were associated with MI at the discovery and replication stages. Further research will be required to determine the functional association of these genes with MI risk, and these associations have to be confirmed in other ethnic populations.

Hydrogen sulfide inhibits nitric oxide production and nuclear factor-kappaB via heme oxygenase-1 expression in RAW264.7 macrophages stimulated with lipopolysaccharide.

Hydrogen sulfide (H(2)S), a regulatory gaseous molecule that is endogenously synthesized by cystathionine gamma-lyase (CSE) and/or cystathionine beta-synthase (CBS) from L-cysteine (L-Cys) metabolism, is a putative vasodilator, and its role in nitric oxide (NO) production is unexplored. Here, we show that at noncytotoxic concentrations, H(2)S was able to inhibit NO production and inducible NO synthase (iNOS) expression via heme oxygenase (HO-1) expression in RAW264.7 macrophages stimulated with lipopolysaccharide (LPS). Both H(2)S solution prepared by bubbling pure H(2)S gas and NaSH, a H(2)S donor, dose dependently induced HO-1 expression through the activation of the extracellular signal-regulated kinase (ERK). Pretreatment with H(2)S or NaHS significantly inhibited LPS-induced iNOS expression and NO production. Moreover, NO production in LPS-stimulated macrophages that are expressing CSE mRNA was significantly reduced by the addition of L-Cys, a substrate for H(2)S, but enhanced by the selective CSE inhibitor beta-cyano-L-alanine but not by the CBS inhibitor aminooxyacetic acid. While either blockage of HO activity by the HO inhibitor, tin protoporphyrin IX, or down-regulation of HO-1 expression by HO-1 small interfering RNA (siRNA) reversed the inhibitory effects of H(2)S on iNOS expression and NO production, HO-1 overexpression produced the same inhibitory effects of H(2)S. In addition, LPS-induced nuclear factor (NF)-kappaB activation was diminished in RAW264.7 macrophages preincubated with H(2)S. Interestingly, the inhibitory effect of H(2)S on NF-kappaB activation was reversed by the transient transfection with HO-1 siRNA, but was mimicked by either HO-1 gene transfection or treatment with carbon monoxide (CO), an end product of HO-1. CO treatment also inhibited LPS-induced NO production and iNOS expression via its inactivation of NF-kappaB. Collectively, our results suggest that H(2)S can inhibit NO production and NF-kappaB activation in LPS-stimulated macrophages through a mechanism that involves the action of HO-1/CO.

3-Hydroxyanthranilic acid, one of L-tryptophan metabolites, inhibits monocyte chemoattractant protein-1 secretion and vascular cell adhesion molecule-1 expression via heme oxygenase-1 induction in human umbilical vein endothelial cells.

Heme oxygenase (HO)-1 is important in the vascular system, and its genetic or pharmacological induction in endothelium would be effective for the prevention and treatment of atherosclerosis. The naturally occurring antioxidant 3-hydroxyanthranilic acid (HA), one of l-tryptophan metabolites formed in vivo along the metabolic route known as the kynurenine pathway during inflammation or infection, was found to induce HO-1 expression and to stimulate nuclear translocation of NF-E2 related factor 2 (Nrf2) in human umbilical vein endothelial cells (HUVECs). Pre-treatment with HA inhibited the secretion of monocyte chemoattractant protein (MCP)-1, the expression of vascular cell adhesion molecule (VCAM)-1 and the activation of transcriptional nuclear factor (NF)-kappaB in HUVECs stimulated with tumor necrosis factor-alpha, the major pro-inflammatory cytokine causing endothelial inflammation. Interestingly, the observed anti-inflammatory effects of HA were mimicked by a HO-1 inducer, cobalt protoporphyrin, and bilirubin, one of HO-1 enzymatic products, but abolished in the presence of a HO-1 inhibitor, tin protoporphyrin. Based on our findings, we suggest that Nrf2-dependent HO-1 expression induced by HA inhibits MCP-1 secretion, VCAM-1 expression and NF-kappaB activation associated with vascular injury and inflammation in atherosclerosis.

1,2,3,4,6-penta-O-galloyl-beta-D-glucose up-regulates heme oxygenase-1 expression by stimulating Nrf2 nuclear translocation in an extracellular signal-regulated kinase-dependent manner in HepG2 cells.

AIM: To examine the potency of 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) as a hepatic heme oxygenase-1 (HO-1) inducer and its regulation in HepG2 cells. METHODS: Expression of HO-1 and NF-E2-related factor 2 (Nrf2) and activation of mitogen-activated protein (MAP) kinases were analyzed by Western blot, immunofluorescence assay, and flow cytometry. Transfections of HO-1 gene, small interfering RNAs for HO-1 and Nrf2, and dominant-negative gene for MAP/extracellular signal-regulated kinase (ERK) were carried out to dissect the signaling pathways leading to HO-1 expression in HepG 2 cells. RESULTS: PGG up-regulated HO-1 expression and this expression conferred cytoprotection against oxidative injury induced by t-butyl hydroperoxide. Moreover, PGG induced Nrf2 nuclear translocation, which was found to be an upstream step of PGG-induced HO-1 expression, and ERK activation, of which pathway was involved in PGG-induced Nrf2 nuclear translocation, HO-1 expression and cytoprotection. CONCLUSION: PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-dependent manner, and HO-1 expression by PGG may serve as one of the important mechanisms for its hepatoprotective effects.

Molecular epidemiology and KSHV K1 subtypes in a Cuban AIDS-Kaposi's sarcoma population.

Kaposi's sarcoma-associated herpesvirus (KSHV) is detected consistently in Kaposi's sarcoma (KS). Because of its dramatic sequence variation, the K1 gene has been used to classify KSHV. We found a diverse array of KSHV subtypes A1, A2, A3, A5, B1, B2, and C3 in 23 Cuban KS samples containing several novel sporadic insertions/deletions in subtypes A and C. The molecular epidemiology of the KSHV subtypes seems to reflect the unique mixed ethnic background of the Cuban population.