Effect of water temperature on the anesthetic effects of alfaxalone in carp (Cyprinus carpio).

Objective: To evaluate the effect of water temperature on intramuscular injected alfaxalone anesthesia in carp (Cyprinus carpio). Materials and Methods: Six healthy adult carp (C. carpio) were intramuscularly injected with alfaxalone (2.5, 5.0, or 7.5 mg/kg) at normal water temperature (25°C) and at low water temperature (2.5 mg/kg, 15°C). The respiratory rate, heart rate (HR), and anesthesia depth (AD) were evaluated every 5 min for 30 min after administration and every 1 h after 60 min after injection. Results: The respiratory and HRs did not change significantly upon alfaxalone injection, regardless of dose. However, a dose-dependent increase in AD scores was observed. Furthermore, 2.5 mg/kg alfaxalone injected in 15°C water showed an almost equal anesthetic effect to that of 5.0 mg/kg alfaxalone in 25°C water. Conclusion: Alfaxalone is readily available, and its anesthetic effect in carp was enhanced by lowering water temperature, illustrating the possibility of intramuscular injection of alfaxalone in fish.

Simplified Synthesis of Renieramycin T Derivatives to Target Cancer Stem Cells via ß-Catenin Proteasomal Degradation in Human Lung Cancer.

Cancer stem cells (CSCs) found within cancer tissue play a pivotal role in its resistance to therapy and its potential to metastasize, contributing to elevated mortality rates among patients. Significant strides in understanding the molecular foundations of CSCs have led to preclinical investigations and clinical trials focused on CSC regulator ß-catenin signaling targeted interventions in malignancies. As part of the ongoing advancements in marine-organism-derived compound development, it was observed that among the six analogs of Renieramycin T (RT), a potential lead alkaloid from the blue sponge Xestospongia sp., the compound DH_32, displayed the most robust anti-cancer activity in lung cancer A549, H23, and H292 cells. In various lung cancer cell lines, DH_32 exhibited the highest efficacy, with IC50 values of 4.06 ± 0.24 µM, 2.07 ± 0.11 µM, and 1.46 ± 0.06 µM in A549, H23, and H292 cells, respectively. In contrast, parental RT compounds had IC50 values of 5.76 ± 0.23 µM, 2.93 ± 0.07 µM, and 1.52 ± 0.05 µM in the same order. Furthermore, at a dosage of 25 nM, DH_32 showed a stronger ability to inhibit colony formation compared to the lead compound, RT. DH_32 was capable of inducing apoptosis in lung cancer cells, as demonstrated by increased PARP cleavage and reduced levels of the proapoptotic protein Bcl2. Our discovery confirms that DH_32 treatment of lung cancer cells led to a reduced level of CD133, which is associated with the suppression of stem-cell-related transcription factors like OCT4. Moreover, DH_32 significantly suppressed the ability of tumor spheroids to form compared to the original RT compound. Additionally, DH_32 inhibited CSCs by promoting the degradation of ß-catenin through ubiquitin-proteasomal pathways. In computational molecular docking, a high-affinity interaction was observed between DH_32 (grid score = -35.559 kcal/mol) and ß-catenin, indicating a stronger binding interaction compared to the reference compound R9Q (grid score = -29.044 kcal/mol). In summary, DH_32, a newly developed derivative of the right-half analog of RT, effectively inhibited the initiation of lung cancer spheroids and the self-renewal of lung cancer cells through the upstream process of ß-catenin ubiquitin-proteasomal degradation.

Renieramycin T Derivative DH_22 Induces p53-dependent Apoptosis in Lung Cancer Cells.

BACKGROUND/AIM: Targeting apoptotic pathways has been identified as a promising strategy for the treatment of lung cancer. We synthesized a new derivative of renieramycin T (RT), named DH_22, and examined its anticancer activities in human lung cancer cells. MATERIALS AND METHODS: The RT derivative DH_22 was chemically modified from RT. The apoptosis-inducing effect was evaluated in A549 cells by annexin V-FITC/PI staining and nuclear staining assay (Hoechst/PI). In addition, the molecular pathway was analyzed by western blot analysis. RESULTS: In the cell viability and nuclear staining tests, DH_22 was discovered to be cytotoxic with an IC50 of 13.27 µM; it induced apoptosis of lung cancer cells. Regarding the mechanism, DH_22 contributed to the activation of p53-dependent apoptosis and decreased the cellular level of c-Myc. The p53-dependent mechanism was indicated by an increase in p53, an induction of the pro-apoptotic Bax protein, and a decrease in the anti-apoptotic B-cell lymphoma 2 (Bcl-2) protein. CONCLUSION: DH_22 has great potential for further development as a new anticancer drug.

Novel Synthetic Derivative of Renieramycin T Right-Half Analog Induces Apoptosis and Inhibits Cancer Stem Cells via Targeting the Akt Signal in Lung Cancer Cells.

Akt is a key regulatory protein of cancer stem cells (CSCs) and is responsible for cancer aggressiveness and metastasis. Targeting Akt is beneficial for the development of cancer drugs. renieramycin T (RT) has been reported to have Mcl-1 targeting activity, and the study of the structure-activity relationships (SARs) demonstrated that cyanide and the benzene ring are essential for its effects. In this study, novel derivatives of the RT right-half analog with cyanide and the modified ring were synthesized to further investigate the SARs for improving the anticancer effects of RT analogs and evaluate CSC-suppressing activity through Akt inhibition. Among the five derivatives, a compound with a substituted thiazole structure (DH_25) exerts the most potent anticancer activity in lung cancer cells. It has the ability to induce apoptosis, which is accompanied by an increase in PARP cleavage, a decrease in Bcl-2, and a diminishment of Mcl-1, suggesting that residual Mcl-1 inhibitory effects exist even after modifying the benzene ring to thiazole. Furthermore, DH_25 is found to induce CSC death, as well as a decrease in CSC marker CD133, CSC transcription factor Nanog, and CSC-related oncoprotein c-Myc. Notably, an upstream member of these proteins, Akt and p-Akt, are also downregulated, indicating that Akt can be a potential target of action. Computational molecular docking showing a high-affinity interaction between DH_25 and an Akt at the allosteric binding site supports that DH_25 can bind and inhibit Akt. This study has revealed a novel SAR and CSC inhibitory effect of DH_25 via Akt inhibition, which may encourage further development of RT compounds for cancer therapy.