Objective: Ingestion of bovine colostrum is known to improve alcoholic hepatitis. As lactoferrin (LF) is abundant in colostrum, the potential for orally administered LF and its pepsin digestion (LFH) to affect alcohol-induced liver injury model rats was investigated. Methods: A control group were given a liquid diet without ethanol, and administered 10 mL/kg of 0.5％ carboxymethyl cellulose (CMC) solution for 6 weeks. Ethanol, LF, and LFH groups were given a liquid diet containing 5％ ethanol and orally administered 10 mL/kg of 0.5％ CMC solution, 3％ LF, or LFH in 0.5％ CMC solution, respectively. At 2, 4, and 6 weeks, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG), and total cholesterol (T-Cho) were examined. At 6 weeks, serum uric acid, histopathology, and gene expression in the liver, as well as the weight of organs, were also evaluated. Results: AST, ALT, TG, T-Cho, and uric acid were significantly lower in the control group than in the ethanol group. ALT at 2 and 4 weeks, T-Cho at 4 weeks, and uric acid were significantly lower in the LFH group than in the ethanol group. Gene expression of IL-11, ADH1, and ALDH2 were significantly higher in the LF and LFH group than in the ethanol group. Conclusion: LF and its pepsin digestion have the potential to induce the production of a hepato-protective cytokine (IL-11) and ethanol-metabolizing enzymes (ADH, ALDH). Ingestion of LFH may suppress liver injury induced by continuous alcohol consumption for a certain period.

 In this study, the role of moonlighting proteins (MP) in heavy metals resistance of lactic acid bacteria were investigated. In the enzyme activity test of cell surface of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in 20 strains, Lactobacillus casei and L. paracasei showed high enzyme activities. The proteins of three strains extracted with distilled water (DW) and phosphate buffered saline (PBS) were detected by SDS-PAGE. Several bands were observed around 40 kDa and 66 kDa in PBS washing, but almost no protein was detected by DW washing. Moreover, no sugar was detected by phenol-sulfuric acid method. The 40 kDa protein of L. rhamnosus TOKAI 45m and L. casei (or L. paracasei) TOKAI 83m was identified as GAPDH, and the 66 kDa protein of TOKAI 45m and TOKAI 65m strains was identified as GroEL. TOKAI 65m and TOKAI 83m strains showed lower cadmium biosorption in PBS-washed cells than in DW-washed cells, but TOKAI 45m strain showed the opposite results. TOKAI 83m strain had a lower mercury biosorption with PBS washing although no difference in TOKAI 45m and TOKAI 65m strains. In cadmium resistance test, there was almost no difference in TOKAI 65m strain, but PBS-washed cells were less resistant in the other two strains. Interestingly, mercury showed the opposite trend to cadmium. These results suggest that MP may protect bacterial cells from cadmium toxicity whereas MP may promote mercury uptake and toxicity at least TOKAI 83m strain. This study strongly suggested that MP might affect heavy metal resistance.

　With rising incidence rates of colorectal cancer (CRC) in East Asian countries, effective chemoprevention measures are in demand. In our previous study, we reported that dietary milk, maitake mushroom (Grifola frondosa), or their combinations prevent development of aberrant crypt foci (ACF) in mice treated with 1,2-dimethylhydrazine (DMH) (Kariyawasam et al., Milk Sci., 68(2), 85-93, 2019). To investigate the preventive mechanism, we used colon mucosa that was obtained from our previous study, and expression levels of inflammation-related cytokines and apoptosis-related proteins were analyzed along with cecum short chain fatty acids (SCFA). The AIN-76 standard diet was used as a control and AIN-76 supplemented with either 10% milk (10 MK), 10% maitake mushroom (10 MM), 5% milk＋5% maitake mushroom (5 Mix), or 10% milk＋10% maitake mushroom (10 Mix) were fed to mice for a period of 11 weeks. Dietary 10 MK or 10 Mix markedly suppressed level of colonic tumor necrosis factor (TNF)-α, an inflammatory cytokine which was increased by DMH administration. Furthermore, the tested food components, modulated other cytokines to suppress colon inflammation compared to the control group. Additionally, we observed that supplementation of these food components significantly reduced anti-apoptotic proteins while increasing apoptosis related proteins, in comparison to the control group. In addition, 10 MM, 5 Mix, and 10 Mix remarkably increased cecum SCFA which was reduced by DMH treatments. Altogether, our results show that dietary milk, maitake mushroom, and their combination suppress ACF formation possibly through suppression of colon inflammation and induction of cell apoptosis. However, protective mechanisms of milk and maitake mushroom are different; therefore, the combined diet may have a more profound impact on improving intestinal health and preventing CRC, when compared to the individual food components.

 Objective: The ingestion of bovine lactoferrin (LF) has antimicrobial and immunomodulatory effects in clinical trials. To understand the mechanisms of action underlying these biological functions of ingested LF, the kinetics of radiolabeled LF in the gastrointestinal tract were investigated. Methods: 1, 4, 7, 10-tetraazacyclododecane-N, N′, N′′, N′′′-tetraacetic acid (DOTA) was reacted with LF to form an amide bond. The amount of DOTA bound to LF was investigated by mass spectrometry. Radioactive yttrium (⁹⁰Y) was chelated to DOTA or DOTA-conjugated LF. ⁹⁰Y-DOTA or ⁹⁰Y-DOTA-conjugated LF was orally administered to mice, and the distribution of the radioactivity was evaluated by whole-body autoradiography. Results: The ratio of DOTA bound to LF was 1：1. The radioactivity was detected mainly in the stomach and partly in the small intestine at 10 min, and slightly in the stomach and mostly in the small intestine at 60 min after the administration of ⁹⁰Y-DOTA-conjugated LF, whereas the radioactivity was detected slightly in the stomach and small intestine, and mostly in the cecum at 60 min after the administration of ⁹⁰Y-DOTA. Conclusion: The radioactivity was mainly detected in the small intestine in the mice administered ⁹⁰Y-DOTA-conjugated LF. Ingested LF may act on the small intestine and perform a variety of biological functions.

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