Current Molecular Pharmacology - Current Issue

With the increasing risk of infections and other serious complications, the underlying molecular mechanism of wound healing impairment in diabetes deserves attention. Cold shock proteins (CSPs), including CIRP and RBM3 are highly expressed in the skin; however, it is unknown whether CSPs are involved in the wound-healing impairment of diabetic skin.

The objective of this study is to investigate the effects of RBM3 on skin wound healing in diabetes.

In vitro experiments, western blot assay was used to test the levels of proteins in HaCaT cells treated with different concentrations of glucose. RBM3 was over-expressed in HaCaT cells using lentivirus particles. Cell viability was analyzed by Cell-Counting Kit-8 assay and colony formation assay. The migration of HaCaT cells at different concentrations of glucose was evaluated by wound healing assay. In vivo experiments, the mouse model of diabetes was established by intraperitoneal injection of streptozotocin. Four weeks later, the mice were anesthetized by intraperitoneal injection of pentobarbital sodium for skin tissue collection or wound healing experiments. RBM3 knockout mice were established by removing exons 2–6 using the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technique and then used in skin wound healing experiments with or without diabetic stress.

In this study, the expression of RBM3, rather than CIRP, was altered in the skin of diabetic specimens, and the RBM3’s overexpression accelerated the cell viability and proliferation of HaCaT cells under high glucose conditions. RBM3 deficiency caused delayed wound healing in RBM3 knockout in diabetic conditions. Moreover. RBM3 enhanced the ERK1/2 signaling pathway, and its inhibitor FR180204 blocked the beneficial effect of RBM3 overexpression on skin wound healing in diabetes.

RBM3 activated the ERK1/2 signal to facilitate skin wound healing in diabetes, offering a novel therapeutic target for its treatment.

Research has revealed that the expression of PD-L1 is significantly upregulated in tumour cells and that the binding of programmed cell death protein 1 (PD-1) to programmed cell death 1 ligand 1 (PD-L1) inhibits the response of T cells, thereby suppressing tumour immunity. Therefore, blocking PD-L1/PD-1 signalling has become an important target in clinical immunotherapy. Some old drugs, namely, non-anticancer drugs, have also been found to have antitumour effects, and maprotiline is one of them. Maprotiline is a tetracyclic antidepressant that has been widely used to treat depression. However, it has not yet been reported whether maprotiline can exert an antitumour effect on melanoma.

This study aimed to investigate the antitumour efficacy of maprotiline in mice with melanoma.

In this study, female C57BL/6 mice were used to establish a tumour-bearing animal model. After treatment with maprotiline, the survival rate of mice was recorded daily. The expression of relevant proteins was detected by Western blotting, the proportion of immune cells was detected by flow cytometry, and the infiltration of immune cells in tumour tissue was detected by immunofluorescence staining.

Maprotiline was found to inhibit the proliferation and migration of B16 cells while increasing cell apoptosis. Importantly, treatment with maprotiline decreased the expression of PD-L1 and increased the proportion of CD4⁺ T cells, CD8⁺ T cells, and NK cells in the spleen. It also increased the infiltration of CD4⁺ and CD8⁺ T cells in tumour tissue.

Our research findings suggest that maprotiline enhances the antitumour immune response in mouse melanoma by inhibiting PD-L1 expression. This study may discover a new PD-L1 inhibitor, providing a novel therapeutic option for the clinical treatment of tumours.

Rheumatoid arthritis (RA) is a systemic inflammatory disease in which TNF-α plays an important role. Fibroblast growth factor receptor 3 (FGFR3) is reportedly involved in RA by regulating the expression of inflammatory cytokines.

This study examined the expression profile of FGFR3 in human synovial biopsy tissues and evaluated its gene-silencing effects on behaviors of synovial cells.

Immunohistochemical staining was used to measure FGFR3 expression in human RA joint tissues. Cell proliferation, migration, and apoptosis assays were used to monitor behavioral changes in cultured synovial SW-982 cells with siRNA-mediated FGFR3 gene silencing. Immunofluorescent staining and western blotting were used to detect molecular changes in the FGFR3 gene-silenced cells.

FGFR3 up-regulation was noted in both cytoplasms and nuclei of synovial cells in human RA joints. FGFR3 siRNA delivery experiments corroborated that FGFR3 knockdown decreased proliferation and migration, and triggered apoptosis of synovial cells. The FGFR3 gene knockdown enhanced constitutive expression of epithelial marker E-cadherin and conversely suppressed expression of epithelial-mesenchymal transition (EMT) markers, including Snail, fibronectin, and vimentin. In addition, FGFR3 silencing significantly reduced the constitutive expressions of TNF-α, transcription factor NF-κΒ, and downstream COX-2 protein and collagenolytic enzyme MMP-9. MAPK inhibition markedly suppressed constitutive levels of NF-κΒ, COX-2, and MMP-9.

Genetic interference of FGFR3 could modulate the expression of inflammatory mediators and EMT markers in the synovial cells. Targeting the FGFR3/MAPK signal axis may be considered a useful therapeutic strategy to ameliorate the development of RA.

The potential mechanism underlying the protective effect of Astragaloside IV (AS-IV) co-treatment with 1, 25-dihydroxy-vitamin D (Vit-D) on neuropathy in diabetic high-fat rats was investigated.

The rat diabetic hyperlipidemia (DH) model was established via streptozotocin and a high-fat diet (HFD). After co-treatment (of AS-IV and Vit-D at respective doses of 50 mg/kg via oral gavage and 30000 IU/kg via intramuscular injection), blood glucose levels, markers of inflammation and oxidative stress, as well as apoptosis and histopathology were evaluated with appropriate techniques.

Co-treatment could effectively reduce blood glucose levels substantially (p< 0.01), improve weight loss, and decrease oral glucose tolerance. Reduced respective sensory and motor nerve conduction velocities in rats were substantially improved (p<0.01) after co-treatment. Also, we observed obvious improvement in DH-induced injured nerve fiber myelin structure and other organ pathologies in co-treated rats. Besides, we observed up-regulated expressions of peroxisomal-proliferator activated receptor-alpha (PPAR-α) and Vit-D receptors (VDR) (p< 0.01) through the western blotting technique. Using the same technique, we also discovered reduced levels of interleukin (IL)1 beta, IL-6, and tumor necrosis factor-alpha, coupled with increased IL-10 and superoxide dismutase levels (p< 0.01). Importantly, co-treatment could effectively exert anti-oxidative and anti-inflammatory effects. Also, co-treatment resulted in the up-regulation of PPAR-α and VDR expressions, inhibition of the renin–angiotensin–aldosterone system, and promotion of β-cell sensitivity to insulin.

The combined application of AS-IV and Vit-D exhibited health effects such as anti-oxidation, regulation of inflammatory factors, and promotion of cell repair, which may be considered as the mechanisms underlying treatment of diabetic peripheral neuropathy and improvement in biochemical indicators.

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.

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.

Esophageal carcinoma (ESCA) is a common malignancy characterized by high morbidity and mortality. Our work managed to dissect the modulatory mechanism of E2F1/miR-29c-3p/COL11A1 in the malignant progression and sensitivity of ESCA cells to sorafenib.

Via bioinformatics approaches, we identified the target miRNA. Subsequently, CCK-8, cell cycle analysis, and flow cytometry were used to check the biological influences of miR-29c-3p on ESCA cells. TransmiR, mirDIP, miRPathDB, and miRDB databases were used as tools for the prediction of upstream transcription factors and downstream genes of miR-29c-3p. The targeting relationship of genes was detected via RNA immunoprecipitation and chromatin immunoprecipitation, which was further validated by dual-luciferase assay. Finally, in vitro experiments revealed the way E2F1/miR-29c-3p/COL11A1 affected sorafenib’s sensitivity, and in vivo experiments were used to verify the way E2F1 and sorafenib impacted ESCA tumor growth.

miR-29c-3p, downregulated in ESCA, could suppress ESCA cell viability, arrest the cell cycle in the G0/G1 phase, and impel apoptosis. E2F1 was found to be upregulated in ESCA and it could abate the transcriptional activity of miR-29c-3p. COL11A1 was found to be a downstream target of miR-29c-3p to enhance cell viability, induce cell cycle arrest in S phase, and constrain apoptosis. Cellular and animal experiments together demonstrated that E2F1 abated the sorafenib’s sensitivity of ESCA cells via miR-29c-3p/COL11A1.

E2F1 affected the viability, cell cycle, and apoptosis of ESCA cells by modulating miR-29c-3p/COL11A1, and it attenuated the sensitivity of ESCA cells to sorafenib, shedding new light on the treatment of ESCA.