Midazolam induces apoptosis in MA-10 mouse Leydig tumor cells through caspase activation and the involvement of MAPK signaling pathway

Drug Repurposing: The Mechanisms and Signaling Pathways of Anti-Cancer Effects of Anesthetics

Cancer is one of the leading causes of death worldwide. There are only limited treatment strategies that can be applied to treat cancer, including surgical resection, chemotherapy, and radiotherapy, but these have only limited effectiveness. Developing a new drug for cancer therapy is protracted, costly, and inefficient. Recently, drug repurposing has become a rising research field to provide new meaning for an old drug. By searching a drug repurposing database ReDO_DB, a brief list of anesthetic/sedative drugs, such as haloperidol, ketamine, lidocaine, midazolam, propofol, and valproic acid, are shown to possess anti-cancer properties. Therefore, in the current review, we will provide a general overview of the anti-cancer mechanisms of these anesthetic/sedative drugs and explore the potential underlying signaling pathways and clinical application of these drugs applied individually or in combination with other anti-cancer agents.

Dexmedetomidine Alleviates Neurogenesis Damage Following Neonatal Midazolam Exposure in Rats through JNK and P38 MAPK Pathways

Midazolam, a widely used anesthetic, inhibits proliferation of neural stem cells (NSCs) and induces neuroapoptosis in neonates. Dexmedetomidine, an effective auxiliary medicine in clinical anesthesia, protects the developing brain against volatile anesthetic-induced neuroapoptosis. Whether dexmedetomidine protects against neurogenesis damage induced by midazolam remains unknown. This study aims to clarify the protective effect of dexmedetomidine on midazolam-induced neurogenesis damage and explore its potential mechanism. Postnatal 7-day-old Sprague-Dawley (SD) rats and cultured NSCs were treated with either normal saline, midazolam, or dexmedetomidine combined with midazolam. The rats were sacrificed at 1, 3, and 7 days after treatment. Cell proliferation was assessed by 5-bromodeoxyurdine (BrdU) incorporation. Cell viability was determined using MTT assay. Cell differentiation and apoptosis were detected by immunofluorescent staining and terminal dUTP nick-end labeling (TUNEL), respectively. The protein levels of p-JNK, p-P38, and cleaved caspase-3 were quantified using Western blotting. Midazolam decreased cell proliferation and increased cell apoptosis in the subventricular zone (SVZ), the subgranular zone (SGZ) of the hippocampus, and cultured NSCs. Moreover, midazolam decreased cell viability and increased the expression of p-JNK and p-P38 in cultured NSCs. Co-treatment with dexmedetomidine attenuated midazolam-induced changes in cell proliferation, viability, apoptosis, and protein expression of p-JNK and p-P38 in cultured NSCs. Midazolam and dexmedetomidine did not affect the differentiation of the cultured NSCs. These results indicate that dexmedetomidine alleviated midazolam-induced neurogenesis damage via JNK and P38 MAPK pathways.

The apoptotic effect of midazolam on the salivary gland of rats and the reversal effect by pilocarpine

To evaluate the apoptosis in parotid glands of rats treated with midazolam associated or not with pilocarpine, 60 Wistar rats were assigned to 6 groups: control groups received saline solution for 30 days (S₃₀) and 60 days (S₆₀) and the other groups received pilocarpine for 60 days (P₆₀), midazolam for 30 days (M₃₀), midazolam for 30 days and 30 days of saline (M₃₀ + S₃₀), and finally midazolam for 30 days and 30 days of midazolam and pilocarpine (M₃₀ + MP₃₀). Histological sections were subjected to the TdT-mediated dUTP-biotin nick and labeling technique. The number of positive and negative cells was quantified, calculating the apoptotic index. ANOVA at 2 criteria and Tukey's test were used. A greater apoptotic index was observed in the M₃₀ (52.79 ± 9.01) and M₃₀ + S₃₀ (62.43 ± 8.52) groups when compared with the S₃₀ (37.94 ± 5.94) and S₆₀ (31.85 ± 9.18) groups, respectively (p < 0.05). There was no difference between M₃₀ + MP₃₀ (30.98 ± 6.19) and S60 (31.85 ± 9.18) groups regarding apoptotic index. Chronic administration of midazolam has been shown to increase the number of apoptotic cells in the parotid glands of rats. However, pilocarpine inhibited this effect, thus inhibiting the apoptosis.

Midazolam activates caspase, MAPKs and endoplasmic reticulum stress pathways, and inhibits cell cycle and Akt pathway, to induce apoptosis in TM3 mouse Leydig progenitor cells

Background

Midazolam (MDZ) has powerful hypnosis, amnesia, anti-anxiety and anticonvulsant effects. Studies have shown that prenatally developmental toxicity of diazepam can be observed in many organs/tissues. However, it remains elusive in male reproductive system.

Materials and methods

TM3 mouse Leydig progenitor cell line was used to determine whether MDZ has any unfavorable effects.

Results

Midazolam significantly decreased cell viability in dose- and time-dependent manners in TM3 cells. In flow cytometry analysis, midazolam significantly increased subG1 phase cell numbers, and annexin V/PI double staining assay further confirmed that MDZ induced apoptosis in TM3 cells. Moreover, MDZ significantly induced the expression of caspase-8 and -3 proteins and the phosphorylation of JNK, ERK1/2 and p38. Besides, MDZ didn’t activate Akt pathway in TM3 cells. Furthermore, the expressions of p-EIF2α, ATF4, ATF3 and CHOP were induced by midazolam, suggesting that midazolam could induce apoptosis through endoplasmic reticulum (ER) stress in TM3 cells. Additionally, the expressions of cyclin A, cyclin B and CDK1 were inhibited by midazolam through the regulation of p53 in TM3 cells, indicating that midazolam could regulate cell cycle to induce apoptosis.

Conclusion

Midazolam could activate caspase, MAPKs and ER stress pathways and impede Akt pathway and cell cycle to induce apoptosis in TM3 mouse Leydig progenitor cells.

Midazolam induces A549 cell apoptosis in vitro via the miR-520d-5p/STAT3 pathway

A novel microRNA, miR-520d-5p, can inhibit proliferation of osteosarcoma cells, but the biological role of miR-520d-5p in lung cancer is notknown. Midazolam can induce apoptosis in many kinds of cancer cells, but there are no reportson its use in lung cancer. We investigated the roles of midazolam and miR-520d-5p in apoptosis induction in a non-small cell lung cancer (NSCLC) cell line (A549). The expression of miR-520d-5p, a signal transducer and activator of transcription 3 (STAT3) and its related protein were measured by quantitative real-time PCR and Western blot. Apoptosis of the NSCLC cells in response to midazolam was determined by MTT assay, flow cytometry, and Western blot. Midazolam significantly induced A549 cell apoptosis and modulated expression of Bcl-2, Bax, and Caspase-3. Additionally, midazolam regulated STAT3 expression in A549 cells, and the siRNA inhibited STAT3 levels, highlighting their roles in the regulation of STAT3 signaling. Midazolam combined with the miR-520d-5p mimic and inhibitor, regulated STAT3 expression and its signaling pathway. Midazolam combined with the miR-520d-5p mimic significantly induced A549 cell apoptosis. Thus, midazolam can induce apoptosis of A549 cells by targeting STAT3 via miR-520d-5p. These findings suggest that midazolam might be a putative anti-cancer approach for NSCLC therapy.

Protective effect of vitexin reduces sevoflurane-induced neuronal apoptosis through HIF-1α, VEGF and p38 MAPK signaling pathway in vitro and in newborn rats

Previous studies have demonstrated that Vitexin possesses antihypertensive, anti-inflammatory and potential anticancer effects. The present study aimed to investigate whether the protective effect of vitexin protects against sevoflurane-induced neuronal apoptosis and the underlying mechanisms of this protective effect. The results demonstrated that Vitexin pretreatment significantly reduced neuronal apoptosis, and inhibited caspase-3 activity, apoptosis regulator BAX protein expression and malondialdehyde levels in sevoflurane-induced newborn rats. In addition, Vitexin pretreatment increased superoxide dismutase and glutathione peroxidase activity. Furthermore, it was revealed that treatment with vitexin induced hypoxia inducible factor 1α subunit (HIF-1α) and vascular endothelial growth factor (VEGF) protein expression, and suppressed phosphorylated-p38 MAP kinase (p38) protein expression in sevoflurane-induced newborn rat. Together, the results of the current study suggest that the protective effect of vitexin reduces sevoflurane-induced neuronal apoptosis through HIF-1α-, VEGF- and p38-associated signaling pathways in newborn rats.

Insights into the Roles of Midazolam in Cancer Therapy

With its high worldwide mortality and morbidity, cancer has gained increasing attention and novel anticancer drugs have become the focus for cancer research. Recently, studies have shown that most anesthetic agents can influence the activity of tumor cells. Midazolam is a γ-aminobutyric acid A (GABA_A) receptor agonist, used widely for preoperative sedation and as an adjuvant during neuraxial blockade. Some studies have indicated the potential for midazolam as a novel therapeutic cancer drug; however, the mechanism by which midazolam affects cancer cells needs to be clarified. This systematic review aims to summarize the progress in assessing the molecular mechanism of midazolam as an anticancer agent.

Midazolam regulated caspase pathway, endoplasmic reticulum stress, autophagy, and cell cycle to induce apoptosis in MA-10 mouse Leydig tumor cells

PURPOSE

Midazolam is widely used as a sedative and anesthetic induction agent by modulating the different GABA receptors in the central nervous system. Studies have also shown that midazolam has an anticancer effect on various tumors. In a previous study, we found that midazolam could induce MA-10 mouse Leydig tumor cell apoptosis by activating caspase cascade. However, the detailed mechanism related to the upstream and downstream pathways of the caspase cascade, such as endoplasmic reticulum (ER) stress, autophagy, and p53 pathways plus cell cycle regulation in MA-10 mouse Leydig tumor cells, remains elusive.

METHODS

Flow cytometry assay and Western blot analyses were exploited.

RESULTS

Midazolam significantly decreased cell viability but increased sub-G1 phase cell numbers in MA-10 cells (P<0.05). Annexin V/propidium iodide double staining further confirmed that midazolam induced apoptosis. In addition, expressions of Fas and Fas ligand could be detected in MA-10 cells with midazolam treatments, and Bax translocation and cytochrome c release were also involved in midazolam-induced MA-10 cell apoptosis. Moreover, the staining and expression of LC3-II proteins could be observed with midazolam treatment, implying midazolam could induce autophagy to control MA-10 cell apoptosis. Furthermore, the expressions of p-EIF2α, ATF4, ATF3, and CHOP could be induced by midazolam, indicating that midazolam could stimulate apoptosis through ER stress in MA-10 cells. Additionally, the expressions of cyclin A, cyclin B, and CDK1 could be inhibited by midazolam, and the phosphorylation of p53, P27, and P21 could be adjusted by midazolam, suggesting that midazolam could manage cell cycle through the regulation of p53 pathway to induce apoptosis in MA-10 cells.

CONCLUSION

Midazolam could induce cell apoptosis through the activation of ER stress and the regulation of cell cycle through p53 pathway with the involvement of autophagy in MA-10 mouse Leydig tumor cells.