Caspofungin Effects on Electrocardiogram of Mice: An Evaluation of Cardiac Safety

Verapamil Enhances the Activity of Caspofungin against Cryptococcus neoformans Coincides with Inhibited Ca2+ /CN Pathway and Damage with Cell Wall Integrity

Currently, the therapeutic effect on cryptococcal infection patients is hindered by toxicity and drug resistance, making it urgent to discover alternative antifungals. Calcium channel blockers, verapamil (VER), have shown effective antifungal effects in several fungi. Here, we found that VER has a significant antifungal effect on Cryptococcus neoformans (C. neoformans). Furthermore, VER has significant synergistic effects with multiple antifungals, even caspofungin (CAS). We confirmed that VER and CAS had a synergistic antifungal effect in the Galleria mellonella. We conducted in-depth research on the possible mechanism of the synergistic impact of VER and CAS. After treatment with VER, the chitosan content of C. neoformans ' cell wall decreased and in dopamine liquid culture medium, we observed the leakage of melanin. Through cell wall fluorescence staining and stress sensitivity analysis, we further demonstrated that VER impaired the integrity of the C. neoformans' cell wall. Another side, VER+CAS modification of C. neoformans membrane permeability, leading to intracellular ROS accumulation and mitochondrial membrane potential changes. VER eliminated the cytoplasmic calcium fluctuations caused by CAS stimulation and down-regulated the genes expression associated with the calcineurin pathway. In addition, we found that the enzyme activity of chitin deacetylase of C. neoformans is significantly influenced by the presence of Ca2+, suggesting that the use of VER may affect the activity. In summary, the synergistic antifungal effect of VER and CAS makes them effective and promising candidates for fungal treatment.

Acute toxicity and antitumor potential of 1,3,4-trisubstituted-1,2,3-triazole dhmtAc-loaded liposomes on a triple-negative breast cancer model

For the first time, compounds developed from the 1,2,3-triazole scaffold were evaluated as novel drugs to treat triple-negative breast cancer (TNBC). Four organic salts were idealized as nonclassical bioisosteres of miltefosine, which is used in the topical treatment for skin metastasizing breast carcinoma. Among them, derivative dhmtAc displayed better solubility and higher cytotoxicity against the human breast adenocarcinoma cell line and mouse 4T1 cell lines, which are representatives of TNBC. In vitro assays revealed that dhmtAc interferes with cell integrity, confirmed by lactate dehydogenase leakage. Due to its human peripheral blood mononuclear cell (PBMC) toxicity, dhmtAc in vivo studies were carried out with the drug incorporated in a long-circulating and pH-sensitive liposome (SpHL-dhmtAc), and the acute toxicity in BALB/c mice was determined. Free dhmtAc displayed cardiac and pulmonary toxicity after the systemic administration of 5 mg/kg doses. On the other hand, SpHL-dhmtAc displayed no toxicity at 20 mg/kg. The in vivo antitumor effect of SpHL-dhmtAc was investigated using the 4T1 heterotopic murine model. Intravenous administration of SpHL-dhmtAc reduced the tumor volume and weight, without interfering with the body weight, compared with the control group and the dhmtAc free form. The incorporation of the triazole compound in the liposome allowed the demonstration of its anticancer potential. These findings evidenced 1,3,4-trisubstituted-1,2,3-triazole as a promising scaffold for the development of novel drugs with applicability for the treatment of patients with TNBC.

Exosomes derived from human placental mesenchymal stem cells ameliorate myocardial infarction via anti-inflammation and restoring gut dysbiosis

BACKGROUND

Myocardial infarction (MI) represents a severe cardiovascular disease with limited therapeutic agents. This study was aimed to elucidate the role of the exosomes derived from human placental mesenchymal stem cells (PMSCs-Exos) in MI.

METHODS

PMSCs were isolated and cultured in vitro, with identification by both transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). To further investigate the effects of PMSC-Exos on MI, C57BL/6 mice were randomly divided into Sham group, MI group, and PMSC-Exos group. After 4 weeks of the intervention, cardiac function was assessed by cardiac echocardiography, electrocardiogram and masson trichrome staining; lipid indicators were determined by automatic biochemical instrument; inflammatory cytokines were measured by cytometric bead array (CBA); gut microbiota, microbial metabolites short chain fatty acids (SCFAs) as well as lipopolysaccharide (LPS) were separately investigated by 16S rRNA high throughput sequencing, gas chromatography mass spectrometry (GC-MS) and tachypleus amebocyte lysate kit; transcriptome analysis was used to test the transcriptional components (mRNA\miRNA\cirRNA\lncRNA) of PMSC-Exos.

RESULTS

We found that human PMSC-Exos were obtained and identified with high purity and uniformity. MI model was successfully established. Compared to MI group, PMSC-Exos treatment ameliorated myocardial fibrosis and left ventricular (LV) remodeling (P < 0.05). Moreover, PMSC-Exos treatment obviously decreased MI molecular markers (AST/BNP/MYO/Tn-I/TC), pro-inflammatory indicators (IL-1β, IL-6, TNF-α, MCP-1), as well as increased HDL in comparison with MI group (all P < 0.05). Intriguingly, PMSC-Exos intervention notably modulated gut microbial community via increasing the relative abundances of Bacteroidetes, Proteobacteria, Verrucomicrobia, Actinobacteria, Akkermansia, Bacteroides, Bifidobacterium, Thauera and Ruminiclostridium, as well as decreasing Firmicutes (all P < 0.05), compared with MI group. Furthermore, PMSC-Exos supplementation increased gut microbiota metabolites SCFAs (butyric acid, isobutyric acid and valeric acid) and decreased LPS in comparison with MI group (all P < 0.05). Correlation analysis indicated close correlations among gut microbiota, microbial SCFAs and inflammation in MI.

CONCLUSIONS

Our study highlighted that PMSC-Exos intervention alleviated MI via modulating gut microbiota and suppressing inflammation.