scholarly journals The Artemiside-Artemisox-Artemisone-M1 Tetrad: Efficacies against Blood Stage P. falciparum Parasites, DMPK Properties, and the Case for Artemiside

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2066
Author(s):  
Liezl Gibhard ◽  
Dina Coertzen ◽  
Janette Reader ◽  
Mariëtte E. van der Watt ◽  
Lyn-Marie Birkholtz ◽  
...  
Keyword(s):  
Late Stage ◽  
Early Stage ◽  
Blood Stage ◽  
Combination Therapies ◽  
Prolonged Incubation ◽  
Model Following ◽  
Synthetic Accessibility ◽  
Artemisinin Combination Therapies

Because of the need to replace the current clinical artemisinins in artemisinin combination therapies, we are evaluating fitness of amino-artemisinins for this purpose. These include the thiomorpholine derivative artemiside obtained in one scalable synthetic step from dihydroartemisinin (DHA) and the derived sulfone artemisone. We have recently shown that artemiside undergoes facile metabolism via the sulfoxide artemisox into artemisone and thence into the unsaturated metabolite M1; DHA is not a metabolite. Artemisox and M1 are now found to be approximately equipotent with artemiside and artemisone in vitro against asexual P. falciparum (Pf) blood stage parasites (IC50 1.5–2.6 nM). Against Pf NF54 blood stage gametocytes, artemisox is potently active (IC50 18.9 nM early-stage, 2.7 nM late-stage), although against the late-stage gametocytes, activity is expressed, like other amino-artemisinins, at a prolonged incubation time of 72 h. Comparative drug metabolism and pharmacokinetic (DMPK) properties were assessed via po and iv administration of artemiside, artemisox, and artemisone in a murine model. Following oral administration, the composite Cmax value of artemiside plus its metabolites artemisox and artemisone formed in vivo is some 2.6-fold higher than that attained following administration of artemisone alone. Given that efficacy of short half-life rapidly-acting antimalarial drugs such as the artemisinins is associated with Cmax, it is apparent that artemiside will be more active than artemisone in vivo, due to additive effects of the metabolites. As is evident from earlier data, artemiside indeed possesses appreciably greater efficacy in vivo against murine malaria. Overall, the higher exposure levels of active drug following administration of artemiside coupled with its synthetic accessibility indicate it is much the preferred drug for incorporation into rational new artemisinin combination therapies.

scholarly journals The Artemiside-artemisox-artemisone-M1 Tetrad: Efficacies Against Blood Stage P. falciparum Parasites, DMPK Properties, and the Case for Artemiside

2021 ◽  
Author(s):  
Liezl Gibhard ◽  
Dina Coertzen ◽  
Janette Reader ◽  
Mariëtte E. van der Watt ◽  
Lyn-Marie Birkholtz ◽  
...  
Keyword(s):  
Active Drug ◽  
Early Stage ◽  
Blood Stage ◽  
Combination Therapies ◽  
Model Following ◽  
Synthetic Accessibility ◽  
Exposure Levels ◽  
Artemisinin Combination Therapies

Because of the need to replace the current clinical artemisinins in artemisinin combination therapies, we are evaluating fitness of amino-artemisinins for this purpose. These include the thiomorpholine derivative artemiside obtained in one scalable synthetic step from dihydroartemisinin (DHA) and the derived sulfone artemisone. We have recently shown that artemiside undergoes facile metabolism via the sulfoxide artemisox into artemisone and thence into the unsaturated metabolite M1; DHA is not a metabolite. Artemisox and M1 are now found to be approximately equipotent with artemiside and artemisone in vitro against asexual P. falciparum (Pf) blood stage parasites (IC50 1.5 – 2.6 nM). Against Pf NF54 blood stage gametocytes, artemisox is potently active (IC50 18.9 nM early-stage, 2.7 nM late-stage). Comparative drug metabolism and pharmacokinetic (DMPK) properties were assessed via po and iv administration of artemiside, artemisox and artemisone in a murine model. Following oral administration, the composite Cmax value of artemiside plus its metabolites artemisox and artemisone formed in vivo is some 2.6-fold higher than that attained following administration of artemisone alone. Given that efficacy of short half-life rapidly-acting antimalarial drugs such as the artemisinins is associated with Cmax, it is apparent that artemiside will be more active than artemisone in vivo, due to additive effects of the metabolites. As is evident from earlier data, artemiside indeed possesses appreciably greater efficacy in vivo against murine malaria. Overall, the higher exposure levels of active drug following administration of artemiside coupled with its synthetic accessibility indicate it is much the preferred drug for incorporation into rational new artemisinin combination therapies.

scholarly journals Evolution of Network Biomarkers from Early to Late Stage Bladder Cancer Samples

2014 ◽  
Vol 2014 ◽  
pp. 1-23 ◽  
Author(s):  
Yung-Hao Wong ◽  
Cheng-Wei Li ◽  
Bor-Sen Chen
Keyword(s):  
Bladder Cancer ◽  
Late Stage ◽  
Early Stage ◽  
Network Structures ◽  
Protein Protein Interaction ◽  
Ppi Networks ◽  
Network Biomarkers ◽  
Two Stages

We use a systems biology approach to construct protein-protein interaction networks (PPINs) for early and late stage bladder cancer. By comparing the networks of these two stages, we find that both networks showed very significantly different mechanisms. To obtain the differential network structures between cancer and noncancer PPINs, we constructed cancer PPIN and noncancer PPIN network structures for the two bladder cancer stages using microarray data from cancer cells and their adjacent noncancer cells, respectively. With their carcinogenesis relevance values (CRVs), we identified 152 and 50 significant proteins and their PPI networks (network markers) for early and late stage bladder cancer by statistical assessment. To investigate the evolution of network biomarkers in the carcinogenesis process, primary pathway analysis showed that the significant pathways of early stage bladder cancer are related to ordinary cancer mechanisms, while the ribosome pathway and spliceosome pathway are most important for late stage bladder cancer. Their only intersection is the ubiquitin mediated proteolysis pathway in the whole stage of bladder cancer. The evolution of network biomarkers from early to late stage can reveal the carcinogenesis of bladder cancer. The findings in this study are new clues specific to this study and give us a direction for targeted cancer therapy, and it should be validated in vivo or in vitro in the future.

scholarly journals Towards new transmission-blocking combination therapies - pharmacokinetics of 10-amino-artemisinins and 11-aza-artemisinin, and comparison with DHA and artemether

2021 ◽  
Author(s):  
Daniel J. Watson ◽  
Lizahn Laing ◽  
Liezl Gibhard ◽  
Ho Ning Wong ◽  
Richard K. Haynes ◽  
...  
Keyword(s):  
Relative Bioavailability ◽  
Total Plasma ◽  
Combination Therapies ◽  
Total Plasma Clearance ◽  
Efficacy Data ◽  
Liver Clearance ◽  
First Time ◽  
Artemisinin Combination Therapies

As artemisinin combination therapies (ACTs) are compromised by resistance, we are evaluating triple combination therapies (TACTs) comprising an amino-artemisinin, a redox drug and third drug with different mode of action. Thus, here we briefly review efficacy data on artemisone, artemiside, other amino-artemisinins and 11-aza-artemisinin, and conduct ADME profiling in vitro and PK profiling in vivo via iv and po administration to mice. The sulfamide derivative has a notably long murine microsomal half-life ( t 1/2 >150 min), low intrinsic liver clearance and total plasma clearance rates ( CL int 189.4, CL tot 32.2 mL/min/kg), and high relative bioavailability (F 59%). Kinetics are somewhat similar for 11-aza-artemisinin ( t 1/2 >150 min, CL int 576.9, CL tot 75.0 mL/min/kg), although bioavailability is lower (F 14%). In contrast, artemether is rapidly metabolized to DHA ( t 1/2 17.4 min) and eliminated ( CL int 855.0, CL tot 119.7 mL/min/kg), and has low oral bioavailability F of 2%. Whilst artemisone displays low t 1/2 of <10 min and high CL int of 302.1, it displays a low CL tot of 42.3 mL/min/kg, and moderate bioavailability F of 32%. Its active metabolite M1 displays a much improved t 1/2 of >150 min and a reduced CL int of 37.4 mL/min/kg. Artemiside has t 1/2 12.4 min and CL int 673.9 and CL tot 129.7 mL/kg/min, likely a reflection of its surprisingly rapid metabolism to artemisone, reported here for the first time. DHA is not formed from any amino-artemisinin. Overall, the efficacy and PK data strongly support the development of selected amino-artemisinins as components of new TACTs.

scholarly journals Continuous infusion of dexamethasone aggravates the damage of cartilage via upregulating p-AKT and impairing articular autophagy in experimental OA model

2020 ◽  
Author(s):  
liang chen ◽  
Zhenhong Ni ◽  
Jinfan Zhang ◽  
Junlan Huang ◽  
Yangli Xie ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Continuous Infusion ◽  
Late Stage ◽  
Early Stage ◽  
Cartilage Matrix ◽  
Chondrocyte Apoptosis ◽  
Western Blot Assay ◽  
Akt Activation

Abstract Objective To explore the effect of dexamethasone (Dex) infusion on articular cartilage and the underlying mechanisms in vitro and in vivo. Methods Destabilization of medial meniscus (DMM)-induced OA mouse model was used in this study. The mice with Dex treatment were sacrificed and then the knee joint samples were obtained for pathological analysis. Mouse primary chondrocytes were isolated and cultured in the presence or absence of Dex, which were used for calcification analysis and western blot assay. Results Dex accelerated the loss of articular cartilage matrix in mice, while it aggravated the damage of cartilage in DMM-induced OA model at the late stage. The calcium content in calcified cartilage layer in the joints from Dex treated OA mice was significantly higher than that from control mice. Dex treatment enhanced mineralization of articular cartilage matrix and leaded to massive apoptosis of chondrocytes in OA model. In addition, Dex caused autophagy of chondrocytes in the early stage, which was decreased at the late stage of Dex treatment. Moreover, we found that the effect of Dex on the mineralization of articular cartilage matrix in mice was related to AKT activation. Conclusions Continuous infusion of Dex can enhance the calcification of cartilage via AKT activation and increase chondrocyte apoptosis through inhibiting autophagy, which aggravates the damage of articular cartilage and accelerates the progression of OA in vivo.

Zeb1 Promotes Odontoblast Differentiation in a Stage-Dependent Manner

2021 ◽  
pp. 002203452098224
Author(s):  
Y. Xiao ◽  
Y.X. Lin ◽  
Y. Cui ◽  
Q. Zhang ◽  
F. Pei ◽  
...  
Keyword(s):  
Late Stage ◽  
Tooth Development ◽  
Early Stage ◽  
Rna Seq ◽  
Cis Elements ◽  
Odontoblast Differentiation ◽  
Odontoblastic Differentiation ◽  
Accessible Chromatin

A comprehensive study of odontoblastic differentiation is essential to understand the process of tooth development and to achieve the ability of tooth regeneration in the future. Zinc finger E-box-binding homeobox 1 ( Zeb1) is a transcription factor expressed in various neural crest–derived tissues, including the mesenchyme of the tooth germ. However, its role in odontoblastic differentiation remains unknown. In this study, we found the expression of Zeb1 gradually increased during odontoblast differentiation in vivo, as well as during induced differentiation of cultured primary murine dental papilla cells (mDPCs) in vitro. In addition, the differentiation of mDPCs was repressed in Zeb1-silenced cells. We used RNA sequencing (RNA -seq) to identify the transcriptome-wide targets of Zeb1 and used assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) to explore the direct targets of Zeb1 in both the early stage (embryonic day 16.5; E16.5) and the late stage (postnatal day 0; PN0) of tooth development. We identified the motifs of transcription factors enriched in Zeb1-dependent accessible chromatin regions and observed that only in the early stage of mDPCs could Zeb1 significantly change the accessibility of chromatin regions. In vivo and in vitro experiments confirmed that silencing of Zeb1 at E16.5 inhibited dentinogenesis. Analysis of RNA-seq and ATAC-seq resulted in the identification of Runx2, a gene directly regulated by Zeb1 during early odontoblast differentiation. Zeb1 enhances the expression of Runx2 by binding to its cis-elements, and ZEB1 interacts with RUNX2. In the late stage of tooth development, we found that ZEB1 could directly bind to and increase the enhancer activity of an element upstream of Dspp and promote dentinogenesis. In this study, for the first time, we revealed that ZEB1 promoted odontoblast differentiation in the early stage by altering chromatin accessibility of cis-elements near genes such as Runx2, while in the late stage, it directly enhanced Dspp transcription, thereby performing a dual role.

scholarly journals Context-Specific Efficacy of Apalutamide Therapy in Preclinical Models of Pten-Deficient Prostate Cancer

Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 3975
Author(s):  
Marco A. De Velasco ◽  
Yurie Kura ◽  
Naomi Ando ◽  
Noriko Sako ◽  
Eri Banno ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Antitumor Activity ◽  
Cancer Cells ◽  
Late Stage ◽  
Early Stage ◽  
Castration Resistant Prostate Cancer ◽  
Akt Inhibitor ◽  
Molecular Features ◽  
Context Specific

Significant improvements with apalutamide, a nonsteroidal antiandrogen used to treat patients suffering from advanced prostate cancer (PCa), have prompted evaluation for additional indications and therapeutic development with other agents; however, persistent androgen receptor (AR) signaling remains problematic. We used autochthonous mouse models of Pten-deficient PCa to examine the context-specific antitumor activity of apalutamide and profile its molecular responses. Overall, apalutamide showed potent antitumor activity in both early-stage and late-stage models of castration-naïve prostate cancer (CNPC). Molecular profiling by Western blot and immunohistochemistry associated persistent surviving cancer cells with upregulated AKT signaling. While apalutamide was ineffective in an early-stage model of castration-resistant prostate cancer (CRPC), it tended to prolong survival in late-stage CRPC. Molecular features associated with surviving cancer cells in CRPC included upregulated aberrant-AR, and phosphorylated S6 and proline-rich Akt substrate of 40 kDa (PRAS40). Strong synergy was observed with the pan-AKT inhibitor GSK690693 and apalutamide in vitro against the CNPC- and CRPC-derived cell lines and tended to improve the antitumor responses in CNPC but not CRPC in vivo. Upregulation of signal transducer and activator of transcription 3 (STAT3) and proviral insertion in murine-1 (PIM-1) were associated with combined apalutamide/GSK690693. Our findings show that apalutamide can attenuate Pten-deficient PCa in a context-specific manner and provides data that can be used to further study and, possibly, develop additional combinations with apalutamide.

scholarly journals Upregulations of Clcn3 and P-Gp Provoked by Lens Osmotic Expansion in Rat Galactosemic Cataract

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Lixia Ji ◽  
Lixia Cheng ◽  
Zhihong Yang
Keyword(s):  
Osmotic Stress ◽  
Early Stage ◽  
Lens Epithelial Cells ◽  
Anterior Capsule ◽  
Glycoprotein P ◽  
Protein Levels ◽  
P Glycoprotein ◽  
Sugar Cataract

Objective.Lens osmotic expansion, provoked by overactivated aldose reductase (AR), is the most essential event of sugar cataract. Chloride channel 3 (Clcn3) is a volume-sensitive channel, mainly participating in the regulation of cell fundamental volume, and P-glycoprotein (P-gp) acts as its modulator. We aim to study whether P-gp and Clcn3 are involved in lens osmotic expansion of galactosemic cataract.Methods and Results.In vitro, lens epithelial cells (LECs) were primarily cultured in gradient galactose medium (10–60 mM), more and more vacuoles appeared in LEC cytoplasm, and mRNA and protein levels of AR, P-gp, and Clcn3 were synchronously upregulated along with the increase of galactose concentration. In vivo, we focused on the early stage of rat galactosemic cataract, amount of vacuoles arose from equatorial area and scattered to the whole anterior capsule of lenses from the 3rd day to the 9th day, and mRNA and protein levels of P-gp and Clcn3 reached the peak around the 9th or 12th day.Conclusion. Galactosemia caused the osmotic stress in lenses; it also markedly leads to the upregulations of AR, P-gp, and Clcn3 in LECs, together resulting in obvious osmotic expansion in vitro and in vivo.

scholarly journals Individual Mycobacterium tuberculosis Resuscitation-Promoting Factor Homologues Are Dispensable for Growth In Vitro and In Vivo

2004 ◽  
Vol 72 (1) ◽  
pp. 515-526 ◽  
Author(s):  
JoAnn M. Tufariello ◽  
William R. Jacobs, ◽  
John Chan
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Stationary Phase ◽  
Essential Gene ◽  
Micrococcus Luteus ◽  
Expression Patterns ◽  
Active Growth ◽  
Prolonged Incubation ◽  
Aerosol Infection

ABSTRACT Mycobacterium tuberculosis possesses five genes with significant homology to the resuscitation-promoting factor (Rpf) of Micrococcus luteus. The M. luteus Rpf is a secreted ∼16-kDa protein which restores active growth to cultures of M. luteus rendered dormant by prolonged incubation in stationary phase. More recently, the Rpf-like proteins of M. tuberculosis have been shown to stimulate the growth of extended-stationary-phase cultures of Mycobacterium bovis BCG. These data suggest that the Rpf proteins can influence the growth of mycobacteria; however, the studies do not demonstrate specific functions for the various members of this protein family, nor do they assess the function of M. tuberculosis Rpf homologues in vivo. To address these questions, we have disrupted each of the five rpf-like genes in M. tuberculosis Erdman, and analyzed the mutants for their growth in vitro and in vivo. In contrast to M. luteus, for which rpf is an essential gene, we find that all of the M. tuberculosis rpf deletion mutant strains are viable; in addition, all show growth kinetics similar to Erdman wild type both in vitro and in mouse organs following aerosol infection. Analysis of rpf expression in M. tuberculosis cultures from early log phase through late stationary phase indicates that expression of the rpf-like genes is growth phase-dependent, and that the expression patterns of the five M. tuberculosis rpf genes, while overlapping to various degrees, are not uniform. We also provide evidence that mycobacterial rpf genes are expressed in vivo in the lungs of mice acutely infected with virulent M. tuberculosis.

scholarly journals Rationally Designing Simple Rod-Like Amphiphilic NIR-Emissive AIE Probes for Precise In-Vivo Detection of Aβ Fibrils/Plaques at A Super-Early Stage

2021 ◽  
Author(s):  
Yipu Wang ◽  
Dong Mei ◽  
Xinyi Zhang ◽  
Da-Hui Qu ◽  
Ju Mei ◽  
...  
Keyword(s):  
High Performance ◽  
Ex Vivo ◽  
Early Stage ◽  
Signal To Noise Ratio ◽  
High Signal ◽  
In Vivo Detection ◽  
Different Strains ◽  
Aβ Fibrils

With increase of social aging, Alzheimer's disease (AD) has been one of the serious diseases threatening human health. The occurrence of A<i>β </i>fibrils<i> </i>or plaques is recognized as the hallmark of AD.<i> </i>Currently, optical imaging has stood out to be a promising technique for the imaging of A<i>β</i> fibrils/plaques and the diagnosis of AD. However, restricted by their poor blood-brain barrier (BBB) penetrability, short-wavelength excitation and emission, and aggregation-caused quenching (ACQ) effect, the clinically used gold-standard optical probes such as <a>thioflavin</a> T (ThT) and thioflavin S (ThS), are not effective enough in the early diagnosis of AD <i>in vivo</i>. Herein, we put forward an “all-in-one” design principle and demonstrate its feasibility in developing high-performance fluorescent probes which are specific to A<i>β</i> fibrils/plaques and promising for super-early <i>in</i>-<i>vivo</i> diagnosis of AD. As a proof of concept, a simple rod-like amphiphilic NIR fluorescent AIEgen, i.e., AIE-CNPy-AD, is developed by taking the specificity, BBB penetration ability, deep-tissue penetration capacity, high signal-to-noise ratio (SNR) into consideration. AIE-CNPy-AD is constituted by connecting the electron-donating and accepting moieties through single bonds and tagging with a propanesulfonate tail, giving rise to the NIR fluorescence, aggregation-induced emission (AIE) effect, amphiphilicity, and rod-like structure, which in turn result in high binding-affinity and excellent specificity to A<i>β</i> fibrils/plaques, satisfactory ability to penetrate BBB and deep tissues, ultrahigh SNR and sensitivity, and high-fidelity imaging capability. <i>In-vitro, ex-vivo,</i> and <i>in-vivo</i> <a>identifying of A<i>β</i> fibrils/plaques</a> in different strains of mice indicate that AIE-CNPy-AD holds the universality to the detection of A<i>β</i> fibrils/plaques. It is noteworthy that AIE-CNPy-AD is even able to trace the small and sparsely distributed A<i>β</i> fibrils/plaques in very young AD model mice such as 4-month-old APP/PS1 mice which are reported to be the youngest mice to have A<i>β</i> deposits in brains, suggesting its great potential in diagnosis and intervention of AD at a super-early stage.

scholarly journals Defining the early stages of intestinal colonisation by whipworms

2020 ◽  
Author(s):  
María A. Duque-Correa ◽  
David Goulding ◽  
Claire Cormie ◽  
Catherine Sharpe ◽  
Judit Gali Moya ◽  
...  
Keyword(s):  
Intestinal Epithelium ◽  
Early Stage ◽  
Proximal Colon ◽  
Host Cells ◽  
Parasitic Nematodes ◽  
Metazoan Parasites ◽  
Multiple Cells ◽  
First Time

ABSTRACTHundreds of millions of people are infected with whipworms (Trichuris trichiura), large metazoan parasites that live in the caecum and proximal colon. Whipworms inhabit distinct multi-intracellular epithelial burrows that have been described as syncytial tunnels. However, the interactions between first-stage (L1) larvae and the host epithelia that determine parasite invasion and establishment in the syncytium remain unclear. In vivo experiments investigating these events have been severely hampered by the limited in situ accessibility to intracellular infective larvae at the bottom of the crypts of Lieberkühn, and the lack of genetic tools such as fluorescent organisms that are readily available for other pathogens but not parasitic nematodes. Moreover, cell lines, which do not mimic the complexity of the intestinal epithelium, have been unsuccessful in supporting infection by whipworm larvae. Here, we show that caecaloids grown in an open crypt-like conformation recapitulate the caecal epithelium. Using this system, we establish in vitro infections with T. muris L1 larvae for the first-time, and provide clear evidence that syncytial tunnels are formed at this early stage. We show that larval whipworms are completely intracellular but woven through multiple cells. Using the caecaloids, we are able to visualise the pathways taken by the larvae as they burrow through the epithelial cells. We also demonstrate that larvae degrade the mucus layers overlaying the epithelium, enabling them to access the cells below. We show that early syncytial tunnels are composed of enterocytes and goblet cells that are alive and actively interacting with the larvae during the first 24 h of the infection. Progression of infection results in damage to host cells and by 72 h post-infection, we show that desmosomes of cells from infected epithelium widen and some host cells appear to become liquified. Collectively, our work unravels processes mediating the intestinal epithelium invasion by whipworms and reveals new specific interactions between the host and the parasite that allow the whipworm to establish on its multi-intracellular niche. Our study demonstrates that caecaloids can be used as a relevant in vitro model to investigate the infection biology of T. muris during the early colonisation of its host.

Sign in / Sign up

Export Citation Format

Share Document