No abstract

A decline in cell-mediated immune response, chronic inflammation and aggravation of humoral immunity was evident which conclusively suggests a skewed Th2 pathway during aging.

Covalently bonded Eudragit S-100 (EU) and chitosan (CS) based colon-specific nanoparticles (CSE NPs) were fabricated as drug carriers for treating colorectal cancers through oral administration. Thiolation of EU and CS prevents the usage of the cross-linking agent. This gives an advantage over the shortcomings of existing EU- and CS-based delivery systems that are associated with large sized nanoparticles with a broad range of size distribution. Paclitaxel (PTX)-loaded CSE NPs presented an efficacy of 8–10% after 48 h of treatment on the HCT 116 cell line signifying uniform distribution of drug inside the cells. About 66% accumulation of cell population was observed in G2/M phase for PTX-loaded CSE NPs, indicating arrest of cell division during the mitotic phase. Biodistribution studies on male Balb/C mice demonstrated retention of CSE NPs in the colon region up to 24 h post oral administration. These findings confer a convenient and effective way for preparing CS- and EU-based drug delivery systems with sustained release and target specificity for colorectal cancers.

The present investigation aimed at identifying the abilities of three different species of probiotic lactobacilli to modulate cellular immune responses in mouse neutrophils and macrophages in vivo over a study period of 60 days. Neutrophil respiratory burst enzymes (cytochrome c reductase and MPO) showed remarkable increased activity (P 0.01) after consumption of milks fermented by different species of probiotics over 30 and 60 days of feeding trials. Enzyme activities (b-galactosidase and bglucuronidase) and nitric oxide production also increased considerably (P 0.01) in macrophages, both in peritoneal fluid and in enriched cell cultures. The effects of enhanced enzyme activities were corroborated by simultaneous increases in the phagocytic activities of neutrophils and macrophages. The increases in cellular functions were invariably maximal during the first 30 days of study and were maintained, but did not increase, over the next 30 days. Further, Lactobacillus helveticus-fed groups were most effective at modulating neutrophil functions whereas Lactobacillus paracasei-fed groups were more potent at enhancing macrophage functions. Together, our results indicate that probiotics have strain specific effects on stimulating cellular functions while not causing excessive stimulation of the immune system over longer feeding periods, thereby resulting in maximum and stable health benefits.

Six strains of lactobacilli belonging to three species (Lactobacillus casei, Lactobacillus acidophilus and Lactobacillus helveticus) were evaluated for probiotic attributes viz. acid tolerance, bile tolerance and cell surface hydrophobicity. All the six strains exhibited probiotic attributes with considerable degree of variation. Three Lactobacillus strains selected on the basis of probiotic attributes were used for preparing three different fermented milks. In order to evaluate the effect of feeding these probiotic fermented milks on macrophage cell function, an in-vivo trial was conducted in mice for a period of 2, 5 and 8 days. The control group of mice was fed with skim milk. The phagocytic activity of macrophages increased significantly (P < 0.05) on feeding fermented milk prepared using L. acidophilus, L. casei and L. helveticus as compared to milk group (control) on 2nd, 5th and 8th day of feeding, respectively. Likewise, the release of β-glucuronidase and β-galactosidase from peritoneal macrophages increased significantly (P < 0.05) on 2nd, 5th and 8th day of feeding as compared to their respective control group (milk). The results thus depict that feeding of probiotic fermented milk enhances phagocytic activity of the macrophages.