Diosmin mitigates dexamethasone-induced osteoporosis in vivo: Role of Runx2, RANKL/OPG, and oxidative stress

Secondary osteoporosis is commonly caused by long-term intake of glucocorticoids (GCs), such as dexamethasone (DEX). Diosmin, a natural substance with potent antioxidant and anti-inflammatory properties, is clinically used for treating some vascular disorders. The current work targeted exploring the protective properties of diosmin to counteract DEX-induced osteoporosis in vivo. Rats were administered DEX (7 mg/kg) once weekly for 5 weeks, and in the second week, vehicle or diosmin (50 or 100 mg/kg/day) for the next four weeks. Femur bone tissues were collected and processed for histological and biochemical examinations. The study findings showed that diosmin alleviated the histological bone impairments caused by DEX. In addition, diosmin upregulated the expression of Runt-related transcription factor 2 (Runx2) and phosphorylated protein kinase B (p-AKT) and the mRNA transcripts of Wingless (Wnt) and osteocalcin. Furthermore, diosmin counteracted the rise in the mRNA levels of receptor activator of nuclear factor-kB ligand (RANKL) and the reduction in osteoprotegerin (OPG), both were induced by DEX. Diosmin restored the oxidant/antioxidant equilibrium and exerted significant antiapoptotic activity. The aforementioned effects were more pronounced at the dose level of 100 mg/kg. Collectively, diosmin has proven to protect rats against DEX-induced osteoporosis by augmenting osteoblast and bone development while hindering osteoclast and bone resorption. Our findings could be used as a stand for recommending supplementation of diosmin for patients chronically using GCs.

Luteolin 4′-Neohesperidoside Inhibits Clinically Isolated Resistant Bacteria In Vitro and In Vivo

Multidrug resistance (MDR) pathogens are usually associated with higher morbidity and mortality rates. Flavonoids are good candidates for the development of new potential antimicrobials. This research investigated whether luteolin 4′-neohesperidoside (L4N) has antibacterial and synergistic activities against four antibiotic-resistant pathogens: methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, fosA-positive shiga toxin producing the Escherichia coli serogroup O111 (STEC O111), and Bacillus cereus. In vitro antimicrobial susceptibility testing revealed highly potent anti-MRSA (MIC of 106.66 ± 6.95 µg/mL), anti-K. pneumoniae (MIC of 53.33 ± 8.47 µg/mL) and anti-STEC O111 (MIC of 26.66 ± 5.23 µg/mL) activities. Significant synergistic combination was clearly noted in the case of gentamycin (GEN) against Gram-negative bacteria. In the case of B. cereus, the combination of vancomycin (VAN) with L4N could efficiently inhibit bacterial growth, despite the pathogen being VAN-resistant (MIC of 213.33 ± 7.9 µg/mL). In vivo evaluation of L4N showed significant decreases in K. pneumoniae and STEC shedding and colonization. Treatment could significantly diminish the levels of pro-inflammatory markers, tumor necrosis factor-alpha (TNF-α), and immunoglobulin (IgM). Additionally, the renal and pulmonary lesions were remarkably enhanced, with a significant decrease in the bacterial loads in the tissues. Finally, this study presents L4N as a potent substitute for traditional antibiotics with anti-STEC O111 and anti-K. pneumoniae potential, a finding which is reported here for the first time.

Tunable femtosecond laser suppresses the proliferation of breast cancer in vitro

Worldwide, the most frequently diagnosed cancer is female breast cancer, and it poses a serious global health threat. Traditional cancer therapies are associated with various side effects, so developing better therapies for breast cancer is necessary, such as laser therapy which could be a promising treatment option. The aim of the current study was to investigate the femtosecond laser irradiation effect on breast cancer using T47D cell line as an in vitro model. Cells were seeded at a density of 5 × 10⁴ cells/well in 96-well plates and incubated overnight. After that, the cells were exposed to femtosecond laser irradiation at various wavelengths falling in the UV, visible, and IR ranges for 3, 5, or 10 min and at a constant power of 100 mW. Cell viability was measured directly and 24 h after femtosecond laser irradiation using MTT assay. When using different femtosecond laser irradiation parameters, especially the 380 and 400 nm femtosecond laser irradiation, there was significant inhibition of breast cancer cell growth, either directly or 24 h after femtosecond laser exposure. Also, 420 and 440 nm significantly affected the viability of the cells. It was also observed that increasing exposure time enhances the observed effect, so 10 min exposure time was the best time of exposure. However, 700, 720, 750, and 780 nm did not significantly affect the cells viability with different exposure times. It was possible to conclude from the aforementioned results that femtosecond laser irradiation exerted a significant anticancer effect against T47D cells. Consequently, the femtosecond laser could be used successfully for breast cancer management.

SAR of Novel 3-Arylisoquinolinones: meta-Substitution on the Aryl Ring Dramatically Enhances Antiproliferative Activity through Binding to Microtubules

A set of meta-substituted 3-arylisoquinolinones have been identified that show substantial cytotoxicity in breast, liver, lung and colon cancer cell lines; these are up to 700-fold more active than the corresponding para analogues. These compounds were initially proposed as inhibitors of N-ribosyl dihydronicotinamide (NRH): quinone oxidoreductase 2 (NQO2) but were found to be inactive against the enzyme. Instead, COMPARE analysis suggested that 6-fluoro-3-(meta-fluorophenyl)isoquinolin-1(2H)-one (4) could mimic colchicine and interact with microtubules, a recognized target for cancer therapy. Subsequent docking, molecular dynamics simulations, and free energy analysis further suggested that compound 4 bound well into the colchicine-binding pocket of tubulin. Indeed, 4 suppressed tubulin polymerization, caused G₂/M cell cycle arrest, and induced apoptosis. Also, 4 inhibited the formation of endothelial cell capillary-like tubes and further disrupted the structure of preestablished tubes; the effects were not observed with para analogue 5. In accordance with this, the computed free energy of binding of 5 to tubulin was lower in magnitude than that for 4 and appeared to arise in part from the inability of the para substituent to occupy a tubulin subpocket, which is possible in the meta orientation. In conclusion, the antiproliferative potential of the novel 3-arylisoquinolinones is markedly influenced by a subtle change in the structure (meta versus para). The meta-substituted isoquinolinone 4 is a microtubule-destabilizing agent with potential tumor-selectivity and antiangiogenic and vascular disrupting features.