PEGylated ofloxacin nanoparticles render strong antibacterial activity against many clinically important human pathogens.

The rise of bacterial resistance against important drugs threatens their clinical utility. Fluoroquinones, one of the most important classes of contemporary antibiotics has also reported to suffer bacterial resistance. Since the general mechanism of bacterial resistance against fluoroquinone antibiotics (e.g. ofloxacin) consists of target mutations resulting in reduced membrane permeability and increased efflux by the bacteria, strategies that could increase bacterial uptake and reduce efflux of the drug would provide effective treatment. In the present study, we have compared the efficiencies of ofloxacin delivered in the form of free drug (OFX) and as nanoparticles on bacterial uptake and antibacterial activity. Although both poly(lactic-co-glycolic acid) (OFX-PLGA) and methoxy poly(ethylene glycol)-b-poly(lactic-co-glycolic acid) (OFX-mPEG-PLGA) nanoformulations presented improved bacterial uptake and antibacterial activity against all the tested human bacterial pathogens, namely, Escherichia coli, Proteus vulgaris, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus, OFX-mPEG-PLGA showed significantly higher bacterial uptake and antibacterial activity compared to OFX-PLGA. We have also found that mPEG-PLGA nanoencapsulation could significantly inhibit Bacillus subtilis resistance development against OFX.

Delivery as nanoparticles reduces imatinib mesylate-induced cardiotoxicity and improves anticancer activity.

Clinical effectiveness of imatinib mesylate in cancer treatment is compromised by its off-target cardiotoxicity. In the present study, we have developed physically stable imatinib mesylate-loaded poly(lactide-co-glycolide) nanoparticles (INPs) that could sustainably release the drug, and studied its efficacy by in vitro anticancer and in vivo cardiotoxicity assays. MTT (methylthiazolyldiphenyl-tetrazolium bromide) assay revealed that INPs are more cytotoxic to MCF-7 breast cancer cells compared to the equivalent concentration of free imatinib mesylate. Wistar rats orally administered with 50 mg/kg INPs for 28 days showed no significant cardiotoxicity or associated changes. Whereas, increased alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels, and reduced white blood cell, red blood cell, and hemoglobin content were observed in the animals administered with free drug. While the histological sections from hearts of animals that received INPs did not show any significant cardiotoxic symptoms, loss of normal architecture and increased cytoplasmic vacuolization were observed in the heart sections of animals administered with free imatinib mesylate. Based on these results, we conclude that nano-encapsulation of imatinib mesylate increases its efficacy against cancer cells, with almost no cardiotoxicity.

Barringtonia acutangula improves the biochemical parameters in diabetic rats / 中国天然药物

AIM@#This study was aimed at evaluating the anti-diabetic activity of the ethanol and aqueous extracts of the leaf material of Barringtonia acutangula in a diabetic animal model.@*METHODS@#The ethanolic and aqueous extracts (250 and 500 mg·kg(-1) body weight) of the leaves of B. acutangula were assessed for antidiabetic activity in a streptozotocin (STZ)-induced diabetes animal model following 21 days of treatment. Glibenclamide (0.6 mg·kg(-1) p.o.) was used as a positive control. The hematological parameters, such as blood glucose level, urea, creatinin, cholesterol, HDL-C, and LDL-C levels were examined.@*RESULTS@#An acute toxicity study (5 000 mg·kg(-1), p.o.) did not produce any symptoms of toxicity. Significant reductions in blood glucose level, and serum total cholesterol and triglyceride levels were noted in animals treated with the extract. The high density lipoprotein-cholesterol (HDLC) level was found to increase as compared with the diabetic control group.@*CONCLUSION@#These results suggest that the leaf aqueous and ethanolic extracts of B. acutangula have anti-diabetic effects. The aqueous extract of B. acutangula produced a similar effect when compared with the ethanol extract. It is proposed that consumption of B. acutangula in some form like tea may help the management of diabetes.