A preparation of cow's late colostrum fraction containing αs1-casein promoted the proliferation of cultured rat intestinal IEC-6 epithelial cells.

Colostrum is a complex mixture of bioactives that promotes neonate growth. Recently, we have found by in vivo study that skimmed, sterilized, and concentrated bovine late colostrum (SCBLC), obtained from a Holstein herd on days 6-7 after parturition, had an ability to maintain intestinal integrity. In the present study we investigated effects of SCBLC on rat intestinal IEC-6 cell proliferation in vitro. A fraction containing αs1-casein was found to have a robust stimulation effect as compared to other protein fractions from SCBLC and even the αs1-casein fraction from milk from other Holstein herds. Furthermore, the SCBLC αs1-casein molecule demonstrated not only slightly slower mobility on both SDS- and native-PAGE than other bovine milk αs1-caseins, but also a peculiar conformation reminiscent of moltenglobule in the circular dichroism spectrum. These findings may be of relevant to the competence of SCBLC to preserve intestinal integrity.

Augmentation of cellular immunity and protection against influenza virus infection by bovine late colostrum in mice.

OBJECTIVE: We investigated whether oral administration of skimmed and concentrated bovine late colostrum (SCBLC) activates the immune system and protects against influenza virus (Flu) infection. METHODS: Murine Peyer's patch (PP) cells (2.5 105) were cultured in 0.1 ml RPMI-1640 supplemented with SCBLC at a concentration of 0, 0.1 or 1.0 mg/ml. To determine the levels of IL-12 and IFN-, supernatants were collected on day 3. Mice were orally administered sterile saline solution (control group), or 400 g/g body weight (SCBLC 400 group) or 2,000 g/g body weight (SCBLC 2,000 group) of SCBLC for three weeks. These mice were measured for natural killer (NK) cells activity on PP cells, splenocytes and lung cells. Also, these mice in the control and SCBLC 2,000 groups were infected with Flu and were measured for the accumulated symptom rate. RESULTS: In PP cells cultured with SCBLC, the levels of IL-12 and IFN- were significantly increased in vitro. Oral administration of SCBLC to mice significantly increased NK cell activity of PP cells, splenocytes and lung cells. The accumulated symptom rate of the SCBLC 2,000 group was significantly lower than that of the control group in a mouse model of Flu infection. CONCLUSION: These results indicate that oral administration of SCBLC activates not only systemic cellular immunity but also local cellular immunity, such as in the respiratory tract, and that activation of cellular immunity is one of the mechanisms of amelioration of Flu infection.

Effects of Salacia chinensis extract on reproductive outcome in rats.

Salaciachinensis is a traditional South and Southeast Asian herb medicine and has been reported to have an antidiabetic function via α-glucosidases inhibitory activity. In this study, the effects of S. chinensis extract (SCE) on reproductive functions of F0 males and females and the effects on survival and growth of F1 offspring were examined using Sprague-Dawley rats. SCE was administered at dose levels of 0, 500, 1000 and 2000 mg/kg/day orally to groups consisting of 25 males and 25 females. Males were dosed once a day in the morning from 8 weeks before mating, throughout the mating period and until the day before necropsy and females were dosed once a day in the morning for 2 weeks before mating and through the mating, gestation and lactation periods (until day 20 of lactation). In all SCE treatment groups, no toxic signs were noted on reproductive outcome such as estrous cycle of F0 females or any parameters for reproductive function or survival, growth, sensory reflex or function development of F1 pups. Therefore, we concluded that SCE has no effects on the reproductive outcome even at a remarkably high dosage level, 2000 mg/kg/day, in Sprague-Dawley rats.

Binding of Norovirus virus-like particles (VLPs) to human intestinal Caco-2 cells and the suppressive effect of pasteurized bovine colostrum on this VLP binding.

Noroviruses (NoVs), which cannot be grown in cell culture, are a major infectious agent of gastroenteritis. An in vitro assay system was established for the evaluation of NoV binding to enterocytes using virus-like particles (VLPs) produced in a baculovirus system expressing a NoV VP1 capsid protein. After confirmation of the purity by MS analysis, VLPs were incubated with human intestinal Caco-2 cells. NoV VLPs were detected clearly by confocal laser microscopy only on a certain population of Caco-2 cells, and were semi-quantified by immunoblotting of cell lysates. Then the suppressive effect of pasteurized bovine colostrum was analyzed on the VLP binding to Caco-2 cells by immunoblotting. The colostrum reduced VLP binding in a dose-dependent manner, at about 50% suppression with 12.5 microg of the colostral proteins. Furthermore, the colostrum contained IgG antibodies reacting to VLPs, suggesting that cross-reactive antibodies in the bovine colostrums block human NoV binding to intestinal cells.

In vitro and in vivo evaluation of the efficacy of bovine colostrum against human rotavirus infection.

We found that skimmed and concentrated bovine late colostrum (SCBLC) obtained from normal cows at 6-7 d after parturition exhibited high potency in inhibiting replication of human rotavirus (HRV) in vitro. Furthermore, prophylactic oral administration of SCBLC once before inoculation of HRV prevented the development of diarrhea in suckling mice in vivo. SCBLC from normal cows might be useful in the prevention of HRV-induced severe gastroenteritis in immunocompromised hosts.