Current Molecular Pharmacology - Current Issue

Artemisinin (ART) is mainly derived from Artemisia annua, a traditional Chinese medicinal plant, and has been found to affect cellular biochemical processes, such as proliferation, angiogenesis, and apoptosis, in addition to its antimalarial properties. However, its effect on cardiac hypertrophy and the underlying mechanisms remain unclear.

This study aimed to investigate the effect of ART on cardiac hypertrophy and explore its possible mechanisms.

A rat model was established by intraperitoneal injection of isoproterenol (ISO) for 3 days, and the degree of myocardial hypertrophy was compared among 5 groups: a control (CON) group, an ISO group, and groups treated with different doses of ART (7 mg/kg/d, 35 mg/kg/d, and 75 mg/kg/d). Echocardiography was used to evaluate cardiac function and structure. The cross-sectional area of cardiomyocytes was measured by hematoxylin and eosin (H&E) staining. The heart weight (HW), body weight (BW), and tail length were measured, and the HW/tail length ratio and the HW/BW ratio were calculated. H9c2 rat cardiomyocytes were cultured, and different amounts of ART were added 2 hours before ISO stimulation. Phalloidin staining was used to evaluate the degree of cell hypertrophy. The levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were quantified in rat plasma and cell supernatant using enzyme-linked immunosorbent assay (ELISA), while the expression levels of p-ERK1/2, p-JNK, and p-p38 MAPK were assessed in the myocardium and H9c2 cells via western blot analysis.

Intragastric administration of ART at a dosage of 35 mg/kg/d or over mitigated the early-stage cardiac hypertrophy induced by ISO in rats led to a reduction in left ventricular posterior wall diastolic thickness, interventricular septal thickness at diastole, lowered ANP and BNP levels, as well as a decrease in HW/tail length and HW/BW ratio. In vitro studies demonstrated that ART at a concentration of 100 μM inhibited ISO-mediated hypertrophy of H9c2 cells. The ISO group showed a higher p-ERK/GAPDH ratio and p-p38 MAPK/GAPDH ratio than the control group both in vivo and in vitro. Although the p-JNK/GAPDH ratio was increased in the ISO group, there was no statistical difference. The p-ERK/GAPDH and p-p38/GAPDH ratios were significantly lower in the ART group than in the ISO group.

The mechanism of ART against cardiac hypertrophy was related to inhibition of the ERK1/2 and p38 MAPK signaling pathways.

Lung cancer is a leading cause of cancer mortality. It is one of the most abundant cancer types clinically, with 2 million new cases diagnosed yearly.

Using clinically collected non-small cell lung cancer (NSCLC) samples, we sought to hypothesize an innovative intact signaling cascade for the disorder.

We dissected snap-frozen NSCLC tissues along with sibling-paired nearby non-tumorous tissues from 108 NSCLC patients. We measured the expression levels of miR-451/ETV4/MMP13 using qRT-PCR and did a thorough investigation of the molecular mechanism for the signaling axis in NSCLC cell line A549. We also studied the epithelial-mesenchymal transition (EMT) process.

The activity of miR-451 was significantly decreased in NSCLC tissues, while the expression levels of ETV4 and MMP13 were remarkably increased. At the same time, miR-451 levels maintained a declining trend across TNM stage I–III. Inversely, ETV4 and MMP13 increased as the TNM stage increased. The miR-451/ETV4/MMP13 signaling axis was closely associated with prognosis in NSCLC patients. Based on in vitro experiments, ETV4 was a direct targeting factor for miRNA-451. Meanwhile, ETV4 promoted the tumor properties of NSCLC cells by directly activating MMP13. Silencing MMP13 blocked the EMT progress of NSCLC cells.

Overall, we hypothesized an impeccable signaling pathway for NSCLC from a new aspect, and this can offer alternative insights for a better understanding of the disorder.

This commentary explores the potential of Vorasidenib, also known as AG-881. This emerging small-molecule inhibitor has garnered substantial attention within the realm of oncology due to its unique mechanism of action and potential therapeutic applications.

Gliomas are common malignant brain tumors characterized by diffuse brain infiltration. World Health Organization grade II and grade III diffuse gliomas are considered lower-grade gliomas (LGGs) and have isocitrate dehydrogenase (IDH) mutations. LGGs are challenging due to their infiltrative nature, making them capable of progressing into higher-grade malignancies. Vorasidenib is a novel therapeutic agent targeting mutant IDH1/2, sparking interest in the field.

Vorasidenib inhibits mutant IDH1/2 through a unique mechanism, reducing the production of the oncometabolite 2-hydroxyglutarate (2-HG). This alteration affects key enzymes and DNA methylation, impacting tumor growth and invasion.

Preclinical studies show vorasidenib's efficacy in inhibiting mutant IDH1/2 and 2-HG production in glioma models. It suppresses tumor growth, making it a potential treatment option.

Early clinical trials demonstrate vorasidenib's clinical activity in non-enhancing gliomas. It reduces 2-hydroxyglutarate levels and tumor cell proliferation, with an objective response rate and prolonged progression-free survival. The drug's safety profile is favorable.

Challenges include identifying predictive biomarkers and optimizing sequencing or combinations with existing therapies. Further research is needed to establish long-term effectiveness, evaluate side effects, and explore combinations with immunotherapy.

Vorasidenib significantly advances LGG treatment, targeting a prevalent mutation and slowing tumor growth. Promising preclinical and clinical evidence and manageable side effects suggest its potential impact on LGG management. However, more research, including large trials, is needed to confirm its efficacy and role in treatment.

Disease relapse and therapy resistance remain serious impediments to treating cancer. Leukemia stem cells (LSC) are therapy resistant and the cause of relapse. A state of deep quiescence appears to enable cancer stem cells (CSC) to acquire new somatic mutations essential for disease progression and therapy resistance. Both normal hematopoietic stem cells (HSC) and LSC share many common features, thereby complicating the safe elimination of LSC. A recent study demonstrated that long lived normal oocytes exist without mitochondrial complex I (MC-1), expressing it in a developmentally regulated fashion, thereby mitigating their vulnerability to ROS. Quiescent CSC rely on mitochondrial FAO, without complex I expression, thereby avoiding the generation of damaging ROS, similar to long lived normal human stem cells. A deeper understanding of the biology of therapy resistance is important for the development of optimal strategies to attain complete leukemia cures.

Here, using scRNA-sequencing and ATAC-seq on primary chronic myelogenous leukemia (CML) patient samples, combined with bioinformatics analyses, we further examine the heterogeneity of a previously characterized in vitro imatinib-selected CD34^-CD38^- CML LSC population. We utilized a series of functional analyses, including single-cell metabolomic and Seahorse analyses, to validate the existence of the deepest quiescent leukemia initiators (LI) subset.

Current study revealed heterogeneity of therapy resistant LSC in CML patients and their existence of two functionally distinct states. The most deeply quiescent LI suppress the expression of MC-1, yet are highly dependent on fatty acid oxidation (FAO) for their metabolic requirements and ATAC-seq demonstrated increased chromatin accessibility in this population, all consistent with an extremely primitive, quiescent stemness transcriptional signature. Importantly, the specific CREB binding protein (CBP)/β-catenin antagonist ICG-001 initiates the differentiation of LSC, including LI, decreases chromatin accessibility with differentiation and increasing expression of MC-1, CD34, CD38 and BCR-ABL1, thereby re-sensitizing them to imatinib.

We investigated the biological aspects related to LSC heterogeneity in CML patients and demonstrated the ability of specific small molecule CBP/β-catenin antagonists to safely eliminate deeply quiescent therapy resistant CSC. These observations may represent an attractive generalizable therapeutic strategy that could help develop better protocols to eradicate the quiescent LSC population.

Psoriasis is an acute to chronic multifunctional inflammatory skin disorder mediated through T-cell activation, dendritic cell intervention, local vascular variations, atypical keratinocyte proliferation, and neutrophil activation, leading to a skin disorder with no permanent cure.

This review aims to find a potent, secure, and dependable medication, with a more scientific examination of herbal resources and recent targeted immunobiological therapies.

Reports evaluating the effectiveness of biologics & herbal remedies for the topical therapy of psoriasis against control therapies were taken into consideration (placebo or active therapy). The work examined cellular circuits involved in inflammation with its immunogenetic mechanism behind various options available for treating psoriasis in addition to the role of agents inducing psoriasis.

The extent of psoriasis can range from small, localized spots to total body coverage, and it can happen at any stage of life. Several theories exist for clarification however, the exact cause of psoriasis is not entirely understood. Researchers have discovered genetic loci linkages, environmental changes, drug induction, lifestyle conditions, some infections, etc. resulting in this disorder. There are numerous known conventional medical treatments for psoriasis, ranging from topical and systemic medicines to phototherapy or combinations of both with recent immunobiological treatment. However, the majority of these treatments are ineffective and have a variety of side effects that limit their long-term usage, such as cutaneous atrophy, tissue toxicity, mutagenicity, and immunosuppression.

Herbal extracts or isolated compounds can be considered as a substitute for conventional psoriasis treatment. Unfortunately, many investigations often provide a small amount of facts about the safety and effectiveness of topically applied herbal remedies for the treatment of psoriasis. Thus, further factual evidences and validations are needed to promote herbal options, which must be supported by rigorous animal studies or clinical trials using standardised materials and compositions.

The study aimed to investigate the effects of low concentrations of mitochondrial uncouplers in endothelial cells on the CpG dinucleotide methylation of the ICAM1 gene promoter. The excessive inflammatory response in the endothelium is responsible for the development of many cardiovascular diseases. Mitochondria are important regulators of endothelial cell functions. Mild uncoupling of oxidative phosphorylation and respiration in endothelial mitochondria exerts a long lasting anti-inflammatory effect. However, the detailed mechanism of the anti-inflammatory activity of mitochondrial uncouplers remains unclear.We hypothesized that mild mitochondrial uncoupling leads to epigenetic changes in genomic DNA contributing to the anti-inflammatory response.

We studied the long-term effects of mitochondria-targeted compounds with the uncoupler’s activities: the antioxidant plastoquinonyl-decyl-triphenylphosphonium (SkQ1), dodecyl-triphenylphosphonium (C12TPP), and 2,4-dinitrophenol (DNP). The mRNA expression of the intercellular adhesion molecule 1 (ICAM1), a marker of inflammatory activation of endothelial cells, was measured by RT-qPCR. Cytosine methylation in the CpG sites of the ICAM1 gene promoter was estimated by bisulfite sequencing of individual clones.

It was found that downregulation of ICAM1 expression caused by DNP and C12TPP was accompanied by an increase in the methylation of CpG sites in the ICAM1 gene promoter. None of the compounds affected intracellular or intramitochondrial ATP levels.

Low concentrations of mitochondrial oxidative phosphorylation uncouplers are able to increase methylation of ICAM1 gene promoter, which corresponds to the observed decrease in the levels of mRNA of this gene. Thus, the change in methylation of the ICAM1 gene promoter may underlie the mechanism of decreased ICAM1 expression caused by mild mitochondrial depolarization. Mitochondrial uncouplers may be exploited as possible therapeutic candidates to treat excessive inflammation in endothelium, by changing the methylation status of genomic DNA.

Glucoregulatory protein 94 (Grp94) is necessary for the post-viral life cycle and plays a quality control role in viral proteins, but the role of Grp94 in regulating viral replication in host cells is not well known. Therefore, finding a compound that can regulate Grp94 will help us to study the mechanism of viral replication. Previously, we synthesized a coumarin pyrazoline derivative HCP1 that is an effective inhibitor of Grp94. We suppose that HCP1 may inhibit viral replication.

This study aimed to investigate the effect of HCP1 on the replication ability of Senecavirus A (SVA), so as to provide a target and a leading compound for revealing the pathogenic mechanism of the virus and developing antiviral drugs.

Rat cell lines BHK-21 and porcine cell lines PK-15 were infected with SVA, and the infected cells were treated with different concentrations of HCP1. The cell viability (CCK-8), virus titer (TCID50), autophagy level, and Grp94 expression were measured.

The results showed that a low concentration of HCP1 decreased viral titer and viral load in BHK-21 and PK-15 cells, and 5μM HCP1 significantly decreased the expression of SVA VP2 protein. In addition, SVA infection can lead to an increased level of autophagy, and HCP1 can inhibit host cell autophagy caused by SVA infection, thereby inhibiting viral replication and infection.

These findings reveal that Grp94 is a key factor in controlling SVA replication, and its inhibitor HCP1 suppresses SVA replication by inhibiting the increase of Grp94 protein level and autophagy induced by SVA. This study will contribute to the development of a new class of small-molecule antiviral drugs.

Our previous work has demonstrated significant effects on the oxidative stress response, mitochondrial function, and oxidative phosphorylation in the livers and intestines of p300 S89A knockin (S89AKI) mice. We now show that this mutation is also associated with brain metabolic defects and neuronal differentiation.

p300 S89A edited P19 cells, and S89AKI mice demonstrated metabolic and neuronal differentiation defects based on proteomic, cell biological and PET imaging studies.

The metabolic and differentiation defects associated with the p300 S89A knockin mutation could be corrected both in vitro and in vivo utilizing the small molecule CBP/beta-catenin antagonist ICG-001.

Rebalancing the equilibrium between CBP/β-catenin versus p300/β-catenin associated transcription, utilizing the small molecule CBP/beta-catenin antagonist ICG-001, enhances mitochondrial oxidative phosphorylation, metabolic function, and neuronal differentiation and may be able to ameliorate the cognitive decline seen in neurodegenerative disorders, including Alzheimer’s Disease.

Physalin B (PB) is one of the main active compounds of Solanaceae plants, with a wide range of biological activities. PB reportedly has the potential to treat Alzheimer’s disease (AD).

In this study, we investigated the effect of PB on Tau phosphorylation and cell apoptosis using Tau-expressing HEK293 cells (HEK293/Tau) as a cellular model.

The optimum concentration of PB to treat HEK293/Tau cells was determined using the CCK-8 assay. Additionally, the expression of FoxO1, Tau-5, p-Tau (T231, S262, and S404), ERK, p-ERK, GSK-3β, and p-GSK-3β was detected using western blotting to determine the effect of PB on Tau phosphorylation. The apoptosis rate was detected using flow cytometry, and the expression of Bax and Bcl-2 was detected using western blotting and verified using real-time quantitative polymerase chain reaction (RT-qPCR). Moreover, cells were transfected with FoxO1 siRNA to downregulate FoxO1 expression, and the expression of the above-mentioned proteins was detected to verify the effect of PB on Tau phosphorylation and cell apoptosis.

After 24 h of PB treatment, the phosphorylation levels of Tau at S404, S262, and T231 sites decreased significantly, and the activities of GSK-3β and ERK were inhibited. PB also reduced cell apoptosis by reducing the expression of Bax and increasing the expression of Bcl-2. In addition, PB decreased Tau phosphorylation and cell apoptosis by upregulating FoxO1.

The natural compound PB exhibited a protective effect in the AD cell model by increasing FoxO1 expression and reducing Tau phosphorylation and cell apoptosis.

Liver fibrosis is associated with the activation of hepatic stellate cells (HSCs). Inhibition of HSCs activation is a strategy for alleviating hepatic fibrogenesis. CD73 is involved in liver disease development, while the mechanism remains unclear.

This study aimed to investigate the effect of CD73 targeting inhibition on liver fibrosis.

Intraperitoneal injection of CCl4 was used to induce liver fibrosis in mice models. Adenosine 5′-(α, β-methylene) diphosphate sodium salt (APCP) was used for CD73 blockade. The siRNA was used to induce CD73 knockdown in HSCs. LX2 and HSC-T6 were used to investigate the role of CD73 in HSCs activation in vitro.

The results showed that APCP treatment could alleviate hepatic fibrosis. In fibrotic liver tissues, CD73 exhibited a positive correlation with markers of HSCs activation. Furthermore, APCP treatment and CD73 knockdown could inhibit HSCs (LX2 and HSC-T6) activation and proliferation. By using RNA sequencing of liver tissues from control, CCl4-mice, and APCP-treated mice, 851 genes that were significantly changed in CCl4 mice (vs. control) were reversed by APCP treatment. These genes were mainly enriched in cell division-associated biological processes. Moreover, we found that CD73 might be associated with autophagy in HSCs. In fibrotic liver tissues and HSCs, ATG5 and Beclin1 expression could be downregulated by CD73 knockdown and APCP treatment.

This study demonstrated the effects and mechanism of CD73 in HSCs activation and proliferation, which presents the therapeutical potential of CD73 blockage for liver fibrosis.