Pharmaceuticals

The global spread of multidrug-resistant (MDR) Gram-negative bacteria, particularly extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii, presents a significant public health challenge by limiting effective antimicrobial treatment options. Cefepime, a fourth-generation cephalosporin with broad-spectrum activity, is increasingly compromised by β-lactamase production, efflux pumps, and porin loss. In response, novel cefepime-based β-lactam/β-lactamase inhibitor (BL/BLI) combinations have been developed to overcome these resistance mechanisms. This review examines preclinical and clinical studies on cefepime-based BL/BLI combinations, specifically cefepime/enmetazobactam, cefepime/taniborbactam, cefepime/zidebactam, and cefepime/nacubactam, as found in the PubMed database. Key findings include the restoration of activity against class A ESBLs with cefepime/enmetazobactam, while cefepime/taniborbactam and cefepime/zidebactam show broader inhibition of serine β-lactamases and selected metallo-β-lactamases. Additionally, zidebactam and nacubactam target penicillin-binding protein 2, enhancing bactericidal potency. Preclinical and early-phase clinical trial data indicate potent in vitro activity and favorable pharmacokinetic/pharmacodynamic (PK/PD) profiles. Specifically, the combination of cefepime with enmetazobactam has demonstrated an optimal Cmax/MIC ratio of 8–10, supporting its efficacy in treating MDR Gram-negative infections. Phase III studies are ongoing to confirm efficacy in complicated infections. Cefepime-based BL/BLI combinations are emerging as promising carbapenem-sparing agents, offering broad-spectrum activity, dual mechanisms of action, and encouraging clinical outcomes. These findings support their inclusion in antimicrobial stewardship strategies aimed at mitigating resistance.

Background/Objectives: Alzheimer’s disease (AD) is a progressive multifactorial neurodegenerative disorder. Current AD therapies offer minimal benefits and do not prevent or repair neuronal damage. More effective therapeutic approaches are needed to restore normal bioenergetics and metabolic function to AD neurons. Simufilam is a small-molecule oral drug that targets filamin A, a scaffolding protein in brain cells. Phase III clinical trials of simufilam failed to show any significant cognitive or functional improvements in AD patients. The purpose of this study is to identify and explain the molecular mechanisms that may have contributed to this drug’s lack of clinical success. Methods: Our study investigates the effects of simufilam on amyloid processing, neuronal health, and mitochondrial functioning in the SH-SY5Y human neuronal cell model. SH-SY5Y cells were differentiated into neurons using 10 µM retinoic acid. Undifferentiated and differentiated SH-SY5Y were exposed to simufilam (5 µM, 50 µM; 24 hr). Results: Simufilam did not affect the expression of genes involved in amyloid processing. Amyloid precursor protein (APP), β-secretase, and α-secretase mRNA levels in simufilam-treated SH-SY5Y cells were all unchanged compared to untreated cells. However, amyloidogenic β-secretase protein was significantly increased (fold change 1.17) at 50 µM of simufilam only in differentiated SH-SY5Y cells without affecting APP or α-secretase protein expression. Simufilam at the 50 µM concentration reduced brain-derived neurotrophic factor protein levels (fold change 0.7) only in differentiated SH-SY5Y. Further, simufilam did not improve mitochondrial genes or structure. Conclusions: Our results align with clinical outcomes and indicate that insufficient activity across multiple tests of ability to impact processes related to neuronal health can serve as a preliminary indicator of limited clinical utility.

Background: Cholestatic liver injury (CLI) is characterized by complex pathogenesis; however, oxidative stress-mediated inflammatory response due to bile acid accumulation in the liver is considered a primary cause. Cynarin (CN), an artichoke phytochemical, has demonstrated different biological activities, including antioxidant and anti-inflammatory ones. The current study aimed to explore the potential hepatoprotective effect of CN on CLI induced by alpha-naphthyl isothiocyanate (ANIT) in mice and investigate the possible involved mechanisms. Methods: Mice received CN (25 and 50 mg/kg) for four consecutive days and were challenged with ANIT (75 mg/kg) once on the second day. Liver injury was examined through biochemical determination of liver injury biomarkers and confirmed by histopathological evaluation. Oxidative stress biomarkers and pro-inflammatory cytokines were detected in the hepatic tissue. RT-PCR, Western blotting, and ELISA were applied to address gene and protein expression of potential underlying molecular targets, including thioredoxin-interacting protein (TXNIP), NLR family pyrin domain-containing 3 (NLRP3) inflammasome, and high-mobility group box 1 (HMGB1). Moreover, nuclear factor kappa-B (NF-κB) activation was determined by immunohistochemical analysis. Results: Our findings revealed that CN remarkably ameliorated ANIT-induced hepatic necro-inflammatory changes and biliary duct injury and restored redox balance in the liver. Mechanistically, CN markedly decreased the expression of TXNIP, NLRP3, active caspase-1, gasdermin D N-terminal (GSDMD-N), interleukin (IL)-1β, and IL-18, which were elevated upon ANIT administration. Moreover, CN suppressed ANIT-induced expression of HMGB1 and NF-κB. Conclusions: Our findings suggest that CN has a protective effect against ANIT-induced CLI in mice that is associated with modulation of the TXNIP/NLRP3 and HMGB1/NF-κB signaling cascades.