Effect of buffalo casein-derived novel bioactive peptides on osteoblast differentiation.

PURPOSE: Epidemiological and intervention studies show that milk consumption in childhood and during adolescence is related to higher bone mineral density. Milk and milk products prevent the bone loss in pre- and postmenopausal women. Apart from calcium, there are other biologically active compounds in milk such as bioactive peptides which may play a role in promoting bone health. Casein is the major protein in milk which has also been reported to have numerous biological active peptides within it. The hypothesis of the present study was to identify the key peptides behind osteoanabolic nature of the milk protein, which further can be used to prepare functional foods to alleviate bone diseases like osteoporosis. Hence, this study was carried out to investigate osteogenic nature of four novel bioactive peptides [PEP1 (EDVPSER), PEP2 (NAVPITPTL), PEP3 (VLPVPQK) and PEP4 (HPHPHLSF)] derived from buffalo casein by in vitro osteoblast differentiation model. METHODS: Calvaria cells were isolated from 3-day-old rat pups, cultured under in vitro conditions till confluence and further used for experiments. Calvarial osteoblast cells were cultured in the presence or absence of peptides including positive controls up to 21 days. Effect of peptides was checked at regular intervals by quantifying osteoblast differentiation marker genes (ALP, OCN and COL-1) expression, alkaline phosphatase activity, osteocalcin level in culture supernatants, mineral deposition by alizarin red staining and caspase-3 and 9 assays. RESULTS: The osteoblast differentiation marker genes (ALP, OCN and COL-1) expression was significantly [(p < 0.01) (p < 0.001)] up-regulated in the presence of these peptides. The peptides also significantly induced alkaline phosphatase activity, osteocalcin level and mineral deposition in comparison with the control. It was also observed that all the four peptides did not show any cytotoxic effect during 21-day treatment period. CONCLUSION: All peptides enhanced osteoblast differentiation along with the positive controls. These results hold an immense scope to use peptides as preventive measure for reducing incidence of osteoporosis. These peptides can also be used as drugs and can be utilized as functional ingredients in functional foods preparation for osteoporosis therapy, but in vivo studies are required for further confirmation.

Aloe vera (Aloe barbadensis Miller) supplemented probiotic lassi prevents Shigella infiltration from epithelial barrier into systemic blood flow in mice model.

The aim of present work was to investigate preventive role of orally administered Aloe vera supplemented probiotic lassi (APL) on Shigella dysenteriae infection in mice. At the end of experimental period (2, 5 and 7 days of challenging), different organs such as spleen, liver, small intestine, large intestine, and peritoneal fluid were collected and assessed for Shigella colonization. Secretary IgA was estimated in intestinal fluid. Blood was collected in heparinized tubes for various haematological studies. Oral administration of APL showed a significant (p < 0.05) reduction in the Shigella counts (log cfu/mL) in all organs as compared to other treatment groups at different intervals after post feeding. Similarly, secretary IgA antibody levels (µg/mL) in intestinal fluid were significantly (p < 0.05) increased in case of APL fed mice. Further, feeding of APL also demonstrated a positive effect on different haematological parameters viz. Hb (gm %), RBC and WBC count. The results indicated the immunoprotective effects of APL against Shigella dysenteriae induced infection in mice.