The enhancement effect of small molecule Lyb24 reveals AzoR as a novel target of polymyxin B.

Given the important role of polymyxin B (PB) in the treatment of drug-resistant Gram-negative bacterial infections, the emergence of PB resistance poses a serious threat to public health. Adjuvant development is a supplementary strategy that can compensate for the lack of novel antibiotics by protecting PB. In this study, we found a small molecule named Lyb24 that showed weak antibacterial activity (minimum inhibitory concentration ≥ 10 µg/ml) but potentiated and revitalized the efficacy of PB against Gram-negative pathogens, including mcr-1- and mgrB-deletion-mediated PB-resistant strains. Our results showed that Lyb24 inhibits the translational levels of genes associated with the modification of lipid A. In addition, Lyb24 increases the permeability, disrupts the integrity and induces the depolarization of the membrane. We further found that both Lyb24 and PB could directly bind to AzoR and inhibit its activity. Structural analysis showed that Lyb24 binds to the isoalloxazine ring of flavin mononucleotide (FMN) through pi-pi stacking and loop η4 of AzoR. A pneumonia model was used to confirm that the activity against clinical PB-resistant Klebsiella pneumoniae was enhanced due to Lyb24 on PB. In conclusion, we provide a potential therapeutic regimen by combining Lyb24 and PB to treat Gram-negative-resistant bacterial infections. Our findings not only explain the synergistic effect of Lyb24, but also expand our knowledge on the mechanism of action of PB.

Indication and adverse event profiles of denosumab and zoledronic acid: based on U.S. FDA adverse event reporting system (FAERS).

Objective: To investigate adverse events (AEs) associated with denosumab (Dmab) and zoledronic acid (ZA), compare their association strengths, and explore potential applications to provide clinical reference. Methods: We collected data from FAERS from January 2004 to November 2022 and mined AE signals for Dmab and ZA using ROR values. We compared signal intensity for same AEs and investigated off-label use. We also examined their AEs in adjuvant therapy for breast and prostate cancer. Results: 154,735 reports of primary suspect drugs were analyzed in the FAERS database (Dmab: 117,857; ZA: 36,878). Dmab and ZA had 333 and 1,379 AE signals, with 189 overlaps. The AEs of Dmab included death (ROR:3.478), osteonecrosis of jaw (ROR:53.025), back pain (ROR:2.432), tooth disorder (ROR:16.18), bone pain (ROR:6.523). For ZA, the AEs included osteonecrosis (ROR:104.866), death (ROR: 3.645), pain (ROR:3.963), osteonecrosis of jaw (ROR: 91.744), tooth extraction (ROR: 142.143). Among overlap signals, Dmab showed higher strength in exostosis of the jaw (ROR: 182.66 vs. 5.769), atypical fractures (ROR: 55.589 vs. 9.123), and atypical femur fractures (ROR:49.824 vs. 4.968). And ZA exhibited stronger associations in abscess jaw (ROR: 84.119 vs. 11.12), gingival ulceration (ROR: 74.125 vs. 4.827), increased bone formation (ROR: 69.344 vs. 3.218). Additionally, we identified 528 off-label uses for Dmab and 206 for ZA, with Dmab mainly used in prostate cancer (1.04%), breast cancer (1.03%), and arthritis (0.42%), while ZA in breast cancer (3.21%), prostate cancer (2.48%), and neoplasm malignant (0.52%). For Dmab in breast cancer treatment, AEs included death (11.6%), disease progression (3.3%), and neutropenia (2.7%), while for ZA included death (19.8%), emotional disorder (12.9%), osteomyelitis (11.7%). For prostate cancer treatment, Dmab`s AEs were death (8.9%), prostate cancer metastatic (1.6%), renal impairment (1.7%), while ZA`s included death (34.4%), general physical health deterioration (19.9%), and hemoglobin decreased (18.9%). Conclusion: Our analysis of FAERS database provided postmarketing surveillance data and revealed different strengths of reported AE signals between Dmab and ZA in some of their common AEs. It's also worth noting that both drugs have potential off-label applications, which could introduce new AEs. This highlights the necessity for safety monitoring when using Dmab and ZA off-label.

Risk of Suicidal Behaviors and Antidepressant Exposure Among Children and Adolescents: A Meta-Analysis of Observational Studies.

Objectives: Although several studies have reviewed the suicidal risk of antidepressants, the conclusions remain inconsistent. We, therefore, performed a meta-analysis of observational studies to address the association between exposure to antidepressants, especially selective serotonin reuptake inhibitors (SSRIs) and the risk of suicide and suicide attempt in children and adolescents. Methods: MEDLINE and Embase were searched from January 1990 to April 2021. Seventeen cohort and case-control studies were identified that reported suicide or suicide attempt in children and young adults (aged 5-25 years) who were exposed to any antidepressants. We extracted the estimates and corresponding 95% confidence intervals (CIs) from each publication. Results: The results showed that antidepressant exposure significantly increased the risk of suicide and suicide attempt when compared with no antidepressant usage among children and adolescents. The pooled relative risk (RR) was 1.38 (95% CI: 1.16-1.64; I 2 = 83.1%). Among the antidepressants, SSRI use was associated with an increased risk of suicide and suicide attempt, and the pooled RR was 1.28 (95% CI: 1.09-1.51; I 2 = 68.8%). In subgroup analysis, the attempted suicidal risk of antidepressant and SSRI was significantly increased (RR = 1.35, 95% CI: 1.13-1.61; I 2 = 86.2% for all antidepressants; and RR = 1.26, 95% CI: 1.06-1.48; I 2 = 73.8% for SSRIs), while the completed suicidal risk of antidepressant and SSRI was not statistically significant (RR = 2.32, 95% CI: 0.82-6.53; I 2 = 6.28% for all antidepressants; and RR = 1.88, 95% CI: 0.74-4.79; I 2 = 52.0% for SSRIs). In addition, the risk of suicide and suicide attempt between SSRIs and other antidepressants was similar (RR 1.13, 95% CI: 0.87-1.46, I 2 = 32.4%). Conclusion: The main findings of this meta-analysis provide some evidence that antidepressant exposure seems to have an increased suicidal risk among children and young adults. Since untreated depression remains one of the largest risk factors for suicide and the efficacy of antidepressants is proven, clinicians should evaluate carefully their patients and be cautious with patients at risk to have treatment emergence or worsening of suicidal ideation (TESI/TWOSI) when prescribing antidepressants to children and young patients.

Downregulation of ACE2 expression by SARS-CoV-2 worsens the prognosis of KIRC and KIRP patients via metabolism and immunoregulation.

Background: Angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) allow entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into host cells and play essential roles in cancer therapy. However, the functions of ACE2 and TMPRSS2 in kidney cancer remain unclear, especially as kidneys are targets for SARS-CoV-2 infection. Methods: UCSC Xena project, the Cancer Genome Atlas (TCGA), and Gene Expression Omnibus (GEO) databases (GSE30589 and GSE59185) were searched for gene expression in human tissues, gene expression data, and clinical information. Several bioinformatics methods were utilized to analyze the correlation between ACE2 and TMPRSS2 with respect to the prognosis of kidney renal clear cell carcinoma (KIRC) and kidney renal papillary cell carcinoma (KIRP). Results: ACE2 expression was significantly upregulated in tumor tissue, while its downregulation was associated with low survival in KIRC and KIRP patients. TMPRSS2 was downregulated in KIRC and KIRP, and its expression was not correlated with patient survival. According to clinical risk factor-based prediction models, ACE2 exhibits predictive accuracy for kidney cancer prognosis and is correlated with metabolism and immune infiltration. In an animal model, ACE2 expression was remarkably downregulated in SARS-CoV-2-infected cells compared to in the control. Conclusion: ACE2 expression is highly correlated with various metabolic pathways and is involved in immune infiltration.it plays a crucial role than TMPRSS2 in diagnosing and prognosis of kidney cancer patients. The overlap in ACE2 expression between kidney cancer and SARS-CoV-2 infection suggests that patients with KIRC or KIRP are at high risk of developing serious symptoms.

[Experimental study of the anti-inflammatory and analgesic effects of diethyl 1,3-dicyclohexyl- 1,2,3,6-tetrahydropyrimidine-4,5-dicarboxylate].

OBJECTIVE: To study the anti-inflammatory and analgesic activities of diethyl 1,3-dicyclohexyl-1,2,3,6-tetrahydropyrimidine-4,5-dicarboxylate (ZL-5010) in vivo and in vitro. METHODS: The analgesic effect of ZL-5010 was evaluated by acetic acid-induced writhing response in mice, and the anti-inflammatory effects was assessed in mice with xylene-induced ear edema and in rats with carrageenan-induced paw edema. Mouse peritoneal exudate cells activated by bacterial lipopolysaccharides (LPS) were used to evaluate the anti-inflammatory effect of ZL-5010 in vitro. The levels of interleukin-1ß (IL -1ß) and tumor necrosis factor-α (TNF-α) in the cell culture supernatant were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS: At the doses of 0.25 and 0.5 mmol/kg, ZL-5010 administered by gavage once daily for 3 days significantly reduced acetic acid-induced writhing frequency and suppressed xylene-induced ear edema in mice, and alleviated paw edema induced by carrageenan in rats (P<0.05). The agent also inhibited the production of the pro-inflammatory cytokines IL-1ß and TNF-α by LPS-induced mouse peritoneal exudate cells in vitro, with the statistically significant minimum effective concentrations of 10 and 20 µmol/L, respectively (P<0.05). CONCLUSION: ZL-5010 administered by gavage has anti-inflammatory and analgesic effects in mice and rats, and in mouse peritoneal exudate cell cultures, the agent also inhibits the production of the pro-inflammatory cytokines IL-1ß and TNF-α.