8-octyl berberine combats Staphylococcus aureus by preventing peptidoglycan synthesis.

Staphylococcus aureus is an important pathogenic bacterium responsible for various organ infections. The serious side effects and the development of antibiotic resistance have rendered the antibiotic therapy against S. aureus increasingly challenging, emphasizing the pressing need for the exploration of novel therapeutic agents. Our research has uncovered the promising antimicrobial properties of 8-octyl berberine (OBBR), a novel compound derived from berberine (BBR), against S. aureus. OBBR exhibited a minimum inhibitory concentration (MIC) of 1.0 µg/mL, which closely approximated that of levofloxacin. Intriguingly, a multipassage resistance assay demonstrated that the MIC of OBBR against S. aureus remained relatively stable, while levofloxacin exhibited a 4-fold increase over 20 days, suggesting that OBBR was less prone to inducing resistance. Mechanistically, our investigation, employing Zeta potential measurements, flow cytometry, scanning electron microscopy, and transmission electron microscopy, unveiled that OBBR induced morphological alterations in the bacteria. Furthermore, it disrupted the bacterial cell wall and membrane by altering membrane potential and compromising membrane integrity. These actions culminated in bacterial disintegration and apoptosis. Transcriptomic analysis shed light on significant downregulation of gene ontology terms, predominantly associated with membranes. The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis implicated OBBR in disturbing peptidoglycan biosynthesis, with the membrane protein MraY emerging as a potential target for OBBR's action against S. aureus. Notably, experiments involving the overexpression of MraY confirmed OBBR's inhibitory effect on peptidoglycan synthesis. Furthermore, molecular docking and cellular thermal shift assay revealed OBBR's direct interaction with MraY, potentially leading to the inhibition of the enzymatic activity of MraY and, consequently, impeding peptidoglycan synthesis. In summary, OBBR, by targeting MraY and inhibiting peptidoglycan synthesis, emerges as a promising alternative antibiotic against S. aureus, offering potential advantages in terms of limited drug resistance development.

Berberine promotes IGF2BP3 ubiquitination by TRIM21 to induce G1/S phase arrest in colorectal cancer cells.

The increasing incidence of colorectal cancer (CRC) has become a major global public health burden. The natural drug Berberine (BBR) has shown potential in preventing CRC, and IGF2 mRNA binding protein 3 (IGF2BP3) may be a target of BBR. This study aims to investigate the mechanisms of BBR acting on IGF2BP3 to improve CRC. The results showed that IGF2BP3 played an important role in the development of CRC. BBR down-regulated IGF2BP3 expression and inhibited CRC growth in mice. Cell thermodynamic stability analysis (CETSA) and drug affinity responsive target stability (DARTS) analysis showed BBR may bind to IGF2BP3. BBR may induce structural changes in IGF2BP3 and decrease its protein stability in cytoplasm. The results from Co-Immunoprecipitation (Co-IP) suggested that BBR promoted the ubiquitination of IGF2BP3 by tripartite motif-containing protein 21 (TRIM21). Through RNA binding protein Immunoprecipitation (RIP) assay, it was found BBR inhibited the stabilization of CDK4/CCND1 mRNA by IGF2BP3 and promoted G1/S phase arrest in CRC cells. Overexpression of IGF2BP3 in vitro and in vivo attenuated the inhibition of CRC growth by BBR. This work demonstrated the potential of BBR targeting to IGF2BP3 in improving CRC and provided a new strategy for clinical treatment on CRC as well as novel anticancer drug design based on IGF2BP3 and TRIM21.

Jatrorrhizine ameliorates Schwann cell myelination via inhibiting HDAC3 ability to recruit Atxn2l for regulating the NRG1-ErbB2-PI3K-AKT pathway in diabetic peripheral neuropathy mice.

Diabetic peripheral neuropathy (DPN) is a chronic complication associated with nerve dysfunction and uncontrolled hyperglycemia. Unfortunately, due to its complicated etiology, there has been no successful therapy for DPN. Our research recently revealed that jatrorrhizine (JAT), one of the active constituents of Rhizoma Coptidis, remarkably ameliorated DPN. This work highlighted the potential mechanism through which JAT relieves DPN using db/db mice. The results indicated that JAT treatment significantly decreased the threshold for thermal and mechanical stimuli and increased nerve conduction velocity. Histopathological analysis revealed that JAT significantly increased the number of sciatic nerve fibers and axons, myelin thickness, and axonal diameters. Additionally, JAT markedly elevated the expression of myelination-associated proteins (MBP, MPZ, and Pmp22). The screening of histone deacetylases (HDAC) determined that histone deacetylase 3 (HDAC3) is an excellent target for JAT-induced myelination enhancement. Liquid chromatography-mass spectrometry-(MS)/MS and coimmunoprecipitation analyses further confirmed that HDAC3 antagonizes the NRG1-ErbB2-PI3K-AKT signaling axis by interacting with Atxn2l to augment SCs myelination. Thus, JAT ameliorates SCs myelination in DPN mice via inhibiting the recruitment of Atxn2l by HDAC3 to regulate the NRG1-ErbB2-PI3K-AKT pathway.

Epiberberine ameliorated diabetic nephropathy by inactivating the angiotensinogen (Agt) to repress TGFß/Smad2 pathway.

BACKGROUND: Diabetic nephropathy (DN) is a severe microvascular complication of diabetes with prominent morbidity and mortality. At present, there are hardly any effective drugs to treat DN. Epiberberine (EPI), an isoquinoline alkaloid, has attracted considerable attention due to its anti-hyperglycemic, anti-hyperlipidemic, and anti-inflammatory functions. However, whether there is a protective effect of EPI on DN has not been reported. PURPOSE: The research was aimed to investigate the activities of EPI alleviating kidney damage in db/db mice and to explore its possible mechanisms. STUDY DESIGN: The db/db mice and high-glucose (HG) induced glomerular mesangial cells (GMCs) were used to explore the protective effect of EPI on DN in vivo and in vitro. METHODS: The changes in fasting blood glucose, metabolic index, renal function, and histopathological morphology in db/db mice were detected to evaluate the therapeutic effect of EPI. Then, renal transcriptome and molecular docking were used to screen the key targets. Subsequently, HG-induced GMCs through mimicing the pathological changes in DN were utilized to study the renal protective effects of EPI and its potential mechanism. RESULTS: The results in vivo showed that EPI administration for 8 weeks significantly alleviated diabetes-related metabolic disorders, improved renal functions, and relieved the histopathological abnormalities of renal tissue, especially renal fibrosis in db/db mice. The results in vitro showed that EPI inhibited the proliferation and induced the G2/M phase arrest of HG-induced GMCs. Moreover, a key gene Angiotensinogen (Agt) was screen out by the RNA-seq of kidney and molecular docking, and EPI reduced Agt, TGFß1, and Smad2 expression in vitro and in vivo. Noteworthy, Agt knockdown by siRNA significantly attenuated these beneficial efficacies exerted by EPI, indicating that Agt played a crucial role in the process of EPI improving DN. CONCLUSION: These findings suggested that EPI might be a potential drug for the treatment of DN dependent on the Agt-TGFß/Smad2 pathway.