Profile of Folate in Breast Milk from Chinese Women over 1-400 Days Postpartum.

Folate is an essential nutrient for growth in early life. This study aimed to determine the levels and compositions of folate in Chinese breast milk samples. This study was part of the Maternal Nutrition and Infant Investigation (MUAI) study. A total of 205 healthy mothers were randomly recruited in Chengdu over 1−400 days postpartum. Five different species of folate, including tetrahydrofolate (THF), 5-methyl-THF, 5,10-methenyl-THF,5-formyl-THF and unmetabolized folic acid (UMFA), were measured for liquid chromatography−tandem mass spectrometry (LC-MS). The median levels of total folate ranged from 12.86 to 56.77 ng/mL in the breast milk of mothers at 1−400 days postpartum, gradually increasing throughout the lactating periods. The median levels of 5-methyl-THF, minor reduced folate (the sum of THF, 5,10-methenyl-THF and 5-formyl-THF) and UMFA were in the ranges of 8.52−40.65 ng/mL, 3.48−16.15 ng/mL and 0.00−1.24 ng/mL during 1−400 days postpartum, respectively. 5-Methyl-THF accounted for more than 65% of the total folate in all breast milk samples. The levels of UMFA in mature breast milk samples were higher in supplement users than nonusers, but not for colostrum and transitional milk samples (p < 0.05). In conclusion, the level of total folate in the breast milk changed along with the prolonged lactating periods, but 5-methyl-THF remains the dominant species of folate in the breast milk of Chinese populations across all entire lactating periods.

Carotenoid Profile in Maternal/Cord Plasma and Changes in Breast Milk along Lactation and Its Association with Dietary Intake: A Longitudinal Study in a Coastal City in Southern China.

In this study, changes of carotenoids in breast milk were observed longitudinally for up to one year. Our study aimed to analyze the profile of carotenoids in breast milk and maternal/cord plasma and its correlation with dietary intake in Guangzhou. Plasma and breast milk samples of five stages during lactation (i.e., colostrum; transitional milk; and early, medium, and late mature milk) were collected from lactating mothers. The food frequency questionnaire (FFQ) was used for collecting data on dietary intake in the corresponding stages. Levels of lutein, zeaxanthin, ß-cryptoxanthin, ß-carotene, and lycopene were analyzed by high-performance liquid chromatography. We found that the total carotenoid level decreased gradually with the extension of lactation and eventually stabilized. Among them, the content of lutein increased from colostrum to transitional milk and decreased thereafter until it plateaued in the mature milk. Furthermore, lutein was reported as the dominant nutrient in maternal plasma, cord plasma, transitional milk, and mature milk at up to 400 days postpartum, while beta-carotene was predominant in colostrum. The content of ß-carotenoid in middle and late mature breast milk was related to dietary intake (r = 1.690, p < 0.05). Carotenoid level in cord blood was lower than that in the mother's plasma and was related to the carotenoid intake in the mother's diet. Correlation of carotenoids between maternal and umbilical cord blood, breast milk, and maternal blood could well reflect the transport of carotenoids. These findings may help to guide mothers' diets during breastfeeding.

Lactational Changes of Phospholipids Content and Composition in Chinese Breast Milk.

Phospholipids are pivotal polar lipids in human milk and essential for infants' growth and development, especially in the brain and cognitive development. Its content and composition are affected by multiple factors and there exist discrepancies in different studies. In this study, we determined five major phospholipids classes (phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine, and sphingomyelin) in 2270 human milk samples collected from 0 to 400 days postpartum in six regions of China. The high-performance liquid chromatography coupled with an evaporative light scattering detector (HPLC-ELSD) was performed to quantify the phospholipids. Total phospholipid median (IQR) content was in a range between 170.38 ± 96.52 mg/L to 195.69 ± 81.80 mg/L during lactation and was higher concentrated in colostrum milk and later stage of lactation (after 200 days postpartum) compared with that in the samples collected between 10 to 45 days postpartum. Variations in five major sub-class phospholipids content were also observed across lactation stages (phosphatidylethanolamine: 52.61 ± 29.05 to 59.95 ± 41.74 mg/L; phosphatidylinositol: 17.65 ± 10.68 to 20.38 ± 8.55 mg/L; phosphatidylserine: 15.98 ± 9.02 to 22.77 ± 11.17 mg/L; phosphatidylcholine: 34.13 ± 25.33 to 48.64 ± 19.73 mg/L; sphingomyelin: 41.35 ± 20.31 to 54.79 ± 35.26 mg/L). Phosphatidylethanolamine (29.18-32.52%), phosphatidylcholine (19.90-25.04%) and sphingomyelin (22.39-29.17%) were the dominant sub-class phospholipids in Chinese breast milk during the whole lactation period. These results updated phospholipids data in Chinese human milk and could provide evidence for better development of secure and effective human milk surrogates for infants without access to breast milk.

Profile of Nucleotides in Chinese Mature Breast Milk from Six Regions.

This study measured the total potentially available nucleoside (TPAN) content in breast milk from six different regions of China as a part of the Maternal Nutrition and Infant Investigation (MUAI) study. A total of 631 breast milk samples were collected from healthy, lactating women with singleton, full-term pregnancies between 40 and 45 days postpartum in Changchun, Chengdu, Lanzhou, Shanghai, Tianjin, and Guangzhou. TPAN and free 5'-monophosphate nucleotide (5'-MNT) contents were determined by high-performance liquid chromatography. The TPAN content of the Chinese mature milk ranged from 11.61 mg/L to 111.09 mg/L, with a median level of 43.26 mg/L. Four types of nucleotides were identified, and the median levels of cytidine monophosphate (CMP), uridine monophosphate (UMP), guanosine monophosphate (GMP), and adenosine monophosphate (AMP) were 22.84 mg/L, 9.37 mg/L, 4.86 mg/L, and 4.80 mg/L, respectively. CMP was the predominant nucleotide, accounting for 52.9% of the TPAN content, while free 5'-MNT accounted for 18.38% of the TPAN content. The distribution pattern of the TPAN content and level of the individual nucleotides were significantly different among the selected regions (p < 0.05), but the result showed no significant differences in the TPAN level in breast milk (p > 0.05). In addition, no correlation was reported between the geographic distribution and TPAN levels. This result showed that TPAN better reflects the level of total potential nucleosides in Chinese breast milk rather than 5'-MNT in free form. CMP, UMP, GMP, and AMP are the only 4 types of nucleotides reported in all detections. In addition, results revealed a large variation of TPAN levels in Chinese breast milk across six regions, so that the median value may not be the optimal fortification level of TPAN for Chinese infant populations.

Gastrointestinal biotransformation and tissue distribution of pterostilbene after long-term dietary administration in mice.

The metabolic fate of dietary compounds is closely related to their biological functions. Pterostilbene (PT) is a methylated stilbene found in many plant foods. Herein, we investigated gastrointestinal biotransformation and tissue distribution of PT in mice fed with 0.05% PT (w/w) for 5 weeks. PT and its major metabolites i.e. PT sulfate (PT-S), pinostilbene, pinostilbene sulfate, hydroxylated PT and hydroxylated PT sulfate were identified and quantified in the mucosa and content of the digestive tissues, blood, urine and vital organs. The results showed PT underwent demethylation, hydroxylation and conjugation in the small intestine, while the conjugated metabolites were largely deconjugated in the colon. Anaerobic fermentation with mouse cecal bacteria demonstrated the microbiota mediated deconjugation and demethylation of PT-S and PT, respectively. In conclusion, oral consumption of PT led to extensive biotransformation in mouse gastrointestinal tract and the metabolites of PT might play important roles in the bioactivity of PT.

Metopimazine is primarily metabolized by a liver amidase in humans.

Metopimazine (MPZ) is a peripherally restricted, dopamine D2 receptor antagonist used for four decades to treat acute nausea and vomiting. MPZ is currently under clinical investigation for the treatment of gastroparesis (GP). MPZ undergoes high first-pass metabolism that produces metopimazine acid (MPZA), the major circulating metabolite in humans. Despite a long history of use, the enzymes involved in the metabolism of MPZ have not been identified. Here we report a series of studies designed to identify potential MPZ metabolites in vitro, determine their clinical relevance in humans, and elucidate the enzymes responsible for their formation. The findings demonstrated that the formation of MPZA was primarily catalyzed by human liver microsomal amidase. Additionally, human liver cytosolic aldehyde oxidase (AO) catalyzes the formation of MPZA, in vitro, although to a much lesser extent. Neither cytochrome P450 enzymes nor flavin-monooxygenases (FMO) were involved in the formation MPZA, although two minor oxidative pathways were catalyzed by CYP3A4 and CYP2D6 in vitro. Analysis of plasma samples from subjects dosed 60 mg of MPZ verified that these oxidative pathways are very minor and that CYP enzyme involvement was negligible compared to microsomal amidase/hydrolase in overall MPZ metabolism in humans. The metabolism by liver amidase, an enzyme family not well defined in small molecule drug metabolism, with minimal metabolism by CYPs, differentiates this drug from current D2 antagonists used or in development for the treatment of GP.

[Contents and isomers distribution of vitamin E in human mature breast milk from six regions of China in 2018-2019].

OBJECTIVE: The study aimed to investigate the contents and isomer composition of vitamin E in mature milk in different regions of China. METHODS: Simultaneously recruited 604 lactating mothers aged(29.58±3.43) from Shanghai, Guangzhou, Tianjin, Chengdu, Lanzhou and Changchun cities. They were mainly primiparas with good education background. A total number of 604 mature milk samples was collected. The contents of α-, γ-, δ-tocopherols and the stereoisomers of α-tocopherol were determined by high performance liquid chromatography(HPLC). RESULTS: The M(P25, P75) concentrations of α-tocopherol, RRR-α-tocopherol, γ-tocopherol and δ-tocopherol in Chinese mature milk were 3.16(2.29, 4.16)mg/L, 2.57(1.77, 3.48)mg/L, 0.89(0.58, 1.27)mg/L and 0.17(0.09, 0.27)mg/L, respectively. The total α-TE level was 3.09(2.22, 4.10)mg/L with statistically regional differences(P<0.001). RRR-α-tocopherol was the predominated stereoisomers of α-tocopherol, accounting for 83.17%(76.36%, 88.43%). The proportion of RRR in Tianjin mature milk was significantly lower than that in Lanzhou(77.11% vs. 86.16%, P<0.001) while breast milk samples from other regions had similar RRR-α-tocopherol proportions(82.82%-85.39%). CONCLUSION: Vitamin E content in mature milk was mainly composed of α-tocopherol. Even though the contents of tocopherols have large regional differences, RRR-α-tocopherol was predominated form in all breast milk samples. It is suggested that RRR-α-tocopherol was the main active form of vitamin E in the early stage of life.

Six Oligosaccharides' Variation in Breast Milk: A Study in South China from 0 to 400 Days Postpartum.

This study investigated the variation in oligosaccharide levels in the breast milk of south Chinese mothers in a prolonged breastfeeding period of up to 400 days postpartum. A total of 488 breast milk samples were collected from 335 healthy mothers at five different time points: 0-5 days, 10-15 days, 40-45 days, 200-240 days, and 300-400 days postpartum. A high-performance anion-exchange chromatography-pulsed amperometric detector (HPAEC-PAD) was used to quantify 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT), 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL). In this study, we found six oligosaccharides that were present in breast milk from 0 to 400 days postpartum. The median value ranges of individual oligosaccharide components in this study were 1013-2891 mg/L 2'-FL, 193-1421 mg/L 3-FL, 314-1478 mg/L LNT, 44-255 mg/L LNnT, 111-241 mg/L 3'-SL, and 23-602 mg/L6'-SL. HMO levels decreased over the lactation periods, except for 3-FL, which increased throughout lactation. The predominant fucosylated and sialylated HMOs were 2'-FL and 6'-SL at 40-45 days postpartum and changed to 3-FL and 3'-SL at 200-240 days postpartum. Results from this study showed that lactating women continue to provide their offspring with a high level of 2'-FL one year after delivery, suggesting that 2'-FL may play an important role for infants in early life. Our findings also provide further evidence in support of breastfeeding after one-year postpartum.

[Fatty acid composition of human breast milk across lactational stages in six representative cities in China from 2018 to 2019].

OBJECTIVE: To investigate the fatty acid composition in breast milk at different lactation stages in six representative cities of China. METHODS: From January 2018 to December 2019, milk sampling of 690 healthy lactating mothers(full-term) in 5 lactation periods of 0-5 days, 10-14 days, 40-45 days, 200-240 days and 300-400 days was collected from 6 representative regions in China, with 23 cases of breast milk received in each lactation stage in each city. Mix it into one mixture, and make a total of 30 mixes. Determination of fatty acids in breast milk was conducted by gas chromatography-flame ionization detector. RESULTS: The contents of total fatty acids(TFA), saturated fatty acids(SFA), monounsaturated fatty acids(MUFA) and polyunsaturated fatty acids(PUFA) in breast milk increased with the progress of lactation and reached a relatively stable level after reaching a peak at 40-45 days. However, the composition ratio of SFA, MUFA and PUFA in TFA remained relatively stable from 0 to 400 days. The ratio of arachidonic to docosahexaenoic(AA/DHA) in breast milk from 0 to 400 days in the six cities ranged from 1.14 to 1.55, and there was no obvious trend of change in the whole lactation stage. The ratio of linoleic acid to alpha-linolenic acid(LA/ALA) in Chinese breast milk ranged from 3.84 to 18.94, showing significant regional variation. CONCLUSION: The content and composition of fatty acids in breast milk of six cities in China vary to a certain extent and show a dynamic change process with the passage of time of lactation.

Carotenoid profile in breast milk and maternal and cord plasma: a longitudinal study in Southwest China.

Carotenoids are increasingly being implicated to have an important role in brain and eye development. This study aimed to quantify the content and profile of carotenoids in human breast milk, maternal plasma and neonatal umbilical cord plasma in Chengdu, an urban area in Southwest China. In this study, fifty-four healthy mothers were enrolled. Maternal blood, umbilical cord blood, colostrum, transitional milk and mature milk were collected. Concentrations of carotenoids (lutein, zeaxanthin, ß-cryptoxanthin, ß-carotene and lycopene) were analysed by HPLC. We found that carotenoid concentrations decreased from colostrum to mature milk. Hydrocarbon carotenoids with weaker polarity decreased more than the polar carotenoids. Lycopene concentrations dropped by 99 %, ß-carotene by 92 %, ß-cryptoxanthin by 83 %, lutein by 32 % and zeaxanthin by 22 %. Lycopene and ß-carotene accounted for 70 % of the total carotenoids in colostrum, and lutein predominated amongst carotenoids in transitional milk and mature milk (51-55 %). Carotenoid concentrations in maternal plasma were much higher than that in cord plasma. Lutein predominated in cord plasma. The concentrations of all carotenoids in maternal plasma were correlated with those of cord plasma and human milk. These results are consistent with selective transport mechanisms in the mammary gland related to the polarity of carotenoids, and each carotenoid has its own implications, which may have different priorities in the early life development of infants. These findings may help guide dietary recommendations for carotenoid inclusion in infant formulas.

Dietary resveratrol attenuated colitis and modulated gut microbiota in dextran sulfate sodium-treated mice.

Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of colitis and that its composition could be modulated by exposure to dietary components. Thus, it may be possible to ameliorate the severity of colitis through administration of dietary components. Herein, we determined the effects of orally administered resveratrol on the gut microbiota composition and the resulting inflammatory status of a dextran sodium sulfate (DSS)-induced colitis mouse model. Our results supported our hypothesis that dietary resveratrol altered the microbial composition and restored microbial community diversity in DSS-treated mice. Specifically, resveratrol effectively decreased the abundance of the genera Akkermansia, Dorea, Sutterella and Bilophila, and increased the proportion of Bifidobacterium in colitic mice. Resveratrol was also able to prevent mouse body weight loss, reduce the disease activity index, attenuate tissue damage, and down-regulate the expression of pro-inflammatory cytokines such as IL-2, IFN-γ, GM-CSF, IL-1ß, IL-6, KC/GRO, and TNF-α in the colon of DSS-treated mice. Pearson's correlation analysis indicated significant correlations between the relative levels of these pro-inflammatory cytokines and alterations of the gut microbiota. Our results demonstrated that dietary resveratrol attenuated the inflammatory status and alleviated gut microbiota dysbiosis in a colitis mouse model.

Non-extractable polyphenols from cranberries: potential anti-inflammation and anti-colon-cancer agents.

Cranberries (Vaccinium macrocarpon) are full of polyphenols, which display various health benefits. Most studies have focused on extractable polyphenols (EPs) rather than non-extractable polyphenols (NEPs) but NEPs may possess important biological functions. The objective of this work was to characterize EP and NEP fractions from whole cranberries and determine their potential as anti-inflammation and anti-colon-cancer agents. Our results showed that of the identified polyphenols, anthocyanins were the major ones in the cranberry EP fraction, while phenolic acids were most abundant in the NEP fraction. The oxygen radical absorbance capacity (ORAC) of the NEPs was significantly higher than that of the EPs. Both the EPs and NEPs showed anti-inflammatory effects in inhibiting LPS-induced production of nitric oxide in macrophages. At the concentrations tested, the NEPs showed significantly higher inhibition of the production of nitric oxide in macrophages than the EPs, which was accompanied by decreased expression of inducible nitric oxide synthase (iNOS) and increased expression of HO-1. EP and NEP samples showed anti-cancer capacities in HCT116 cells. And the NEPs showed stronger inhibitory effects on the viability and colony formation capacity of human colon cancer HCT116 cells than the EPs. In a flow cytometry analysis, the NEPs caused cell cycle arrest at the G0/G1 phase and induced significant cellular apoptosis in colon cancer cells. Overall, our results suggested that both the EP and NEP fractions from cranberries were bioactive, and importantly, the NEP fraction showed promising anti-inflammation and anti-colon-cancer potential.

Dietary cranberry suppressed colonic inflammation and alleviated gut microbiota dysbiosis in dextran sodium sulfate-treated mice.

Increased consumption of fruits may decrease the risk of chronic inflammatory diseases including inflammatory bowel disease (IBD). Gut microbiota dysbiosis plays an important etiological role in IBD. However, the mechanisms of action underlying the anti-inflammatory effects of dietary cranberry (Vaccinium macrocarpon) in the colon and its role on gut microbiota were unclear. In this study, we determined the anti-inflammatory efficacy of whole cranberry in a mouse model of dextran sodium sulfate (DSS)-induced colitis, as well as its effects on the structure of gut microbiota. The results showed that dietary cranberry significantly decreased the severity of colitis in DSS-treated mice, evidenced by increased colon length, and decreased disease activity and histologic score of colitis in DSS-treated mice compared to the positive control group (p < 0.05). Moreover, the colonic levels of pro-inflammatory cytokine (IL-1ß, IL-6 and TNF-α) were significantly reduced by cranberry supplementation (p < 0.05). Analysis of the relative abundance of fecal microbiota in phylum and genus levels revealed that DSS treatment significantly altered the microbial structure of fecal microbiota in mice. α diversity was significantly decreased in the DSS group, compared to the healthy control group. But, cranberry treatment significantly improved DSS-induced decline in α-diversity. Moreover, cranberry treatment partially reversed the change of gut microbiota in colitic mice by increasing the abundance of potential beneficial bacteria, for example, Lactobacillus and Bifidobacterium, and decreasing the abundance of potential harmful bacteria, such as Sutterella and Bilophila. Overall, our results for the first time demonstrated that modification of gut microbiota by dietary whole cranberry might contribute to its inhibitory effects against the development of colitis in DSS-treated mice.

The gastrointestinal fate of limonin and its effect on gut microbiota in mice.

The gut microbiota plays a critical role in human health. Diets could modulate the gut microbiota, which in turn may contribute to altered health outcomes by way of changing the relative risk of chronic diseases. Limonin, widely found in citrus fruits, has been reported to possess multiple beneficial health effects. However, the gastrointestinal fate of limonin and its effect on gut microbiota remain unknown. Herein, mice were fed a diet containing 0.05% limonin (w/w) for 9 weeks. Liquid chromatography-mass spectrum analysis showed that limonin was concentrated along the gastrointestinal tract and reached 523.14 nmol g-1 in the colon lumen. Compared to control mice, colonic microbiota richness was significantly increased by limonin. Gut microbiota community was also clearly distinct from the control group as shown by Principle Coordinate Analysis. Additionally, the relative abundance of 22 genera (relative abundance >0.1%) was altered significantly. Among these, generally regarded probiotics (Lactobacillus and Bifidobacterium) were reduced, which was not due to direct inhibitory effect of limonin. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, amino acid metabolism, lipid, metabolism and immune system function were predicted to be upregulated, and immune system disease and infectious disease markers were predicted to be suppressed dramatically by limonin based on gut microbiota composition. Within the infectious disease category, bacterial toxin and Staphylococcus aureus infection markers were suppressed significantly with limonin treatment. Collectively, our study provides the first line of evidence that oral intake of limonin could shift gut microbiota composition and its functions, which warrants further investigation to determine its implication in human health.

Dietary Intake of Whole Strawberry Inhibited Colonic Inflammation in Dextran-Sulfate-Sodium-Treated Mice via Restoring Immune Homeostasis and Alleviating Gut Microbiota Dysbiosis.

Strawberry (Fragaria chiloensis) is a major edible berry with various potential health benefits. This study determined the protective effects of whole strawberry (WS) against dextran-sulfate-sodium-induced colitis in mice. In colitic mice, dietary WS reduced the disease activity index, prevented the colon shortening and spleen enlargement, and alleviated the colonic tissue damages. The abundance of proinflammatory immune cells was reduced by dietary WS in the colonic mucosa, which was accompanied by the suppression of overproduction of proinflammatory cytokines. Western blotting and immunohistochemical analysis revealed that dietary WS decreased the expression of proinflammatory proteins in the colonic mucosa. Moreover, dietary WS partially reversed the alteration of gut microbiota in the colitic mice by increasing the abundance of potential beneficial bacteria, e.g., Bifidobacterium and Lactobacillus, and decreasing the abundance of potential harmful bacteria, e.g., Dorea and Bilophila. Dietary WS also restored the decreased production of short-chain fatty acids in the cecum of the colitic mice. The results revealed the anti-inflammatory effects and mechanisms of dietary WS in the colon, which is critical for the rational utilization of strawberry for the prevention of inflammation-driven diseases.

Chemopreventive Effects of Whole Cranberry (Vaccinium macrocarpon) on Colitis-Associated Colon Tumorigenesis.

SCOPE: There are growing interests in using a whole-food-based approach to prevent chronic diseases due to potential synergistic interactions among different bioactive components within the whole foods. North American cranberry (Vaccinium macrocarpon), a polyphenol-rich fruit, has been shown to exert multiple beneficial health effects. METHODS AND RESULTS: For the first time, the protective effects of whole cranberry powder (WCP) are determined against colitis-associated mouse colon tumorigenesis induced by azoxymethane (AOM) and dextran sulfate sodium (DSS). The results show that dietary administration of WCP (1.5%, w/w in the diet) significantly suppresses colon tumorigenesis as indicated by the reduced tumor incidence, multiplicity, burden, and average tumor size in WCP-fed mice compared to the positive control mice. Both gene and protein expression levels of pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α are markedly attenuated by WCP treatment in the colon of AOM/DSS-treated mice. Moreover, WCP profoundly modulates multiple signaling pathways/proteins related to inflammation, cell proliferation, apoptosis, angiogenesis, and metastasis in the colon, which is closely associated with the inhibitory effects of WCP on colon tumorigenesis. CONCLUSION: Overall, the results demonstrate chemopreventive effects of WCP on colon tumorigenesis in mice, providing a scientific basis for using the whole cranberry as a functional food to promote colon health in humans.

Lactoferrin level in breast milk: a study of 248 samples from eight regions in China.

Lactoferrin plays an important role in infant gastrointestinal health and immunity responses. This study measured the change of the lactoferrin level in breast milk over the lactation time in Chinese women, and explored potential influencing factors in terms of various maternal factors. 248 lactating women were recruited from eight different regions across China, covering 330 days of lactation. The nutrition information of each woman as well as the gender information of infants were collected. Breast milk lactoferrin level was determined by ultra-performance liquid chromatography (UPLC). A twenty-four-hour maternal food recall was used to collect the dietary information. The lactoferrin level decreased progressively from day 1 to day 30 (p < 0.01), and remained constant from day 31 to day 330. Among the eight regions, the breast milk samples from Gansu contained the highest mean lactoferrin level (1.40 g L-1) while the breast milk samples from Zhejiang contained the least mean lactoferrin level, 0.94 g L-1 (p < 0.01). Dietary pattern and maternal BMI showed no correlation with the breast milk lactoferrin level. Maternal ethnicity and age were associated with the breast milk lactoferrin level. The breast milk samples collected from Tibetan ethnicity had 1.45 g L-1 lactoferrin while those collected from Dai ethnicity had 1.02 g L-1 lactoferrin. Women in the elder age group (30 years old and above) had 0.95 g L-1 breast milk lactoferrin, which was significantly lower than the lactoferrin level (1.3 g L-1) in the younger age group (20-25 years old) (p < 0.01). In conclusion, this study showed that lactoferrin levels in the breast milk of Chinese lactating women were influenced by lactation time. Besides, ethnicity and maternal age were two impact factors on the breast milk lactoferrin level.

Synergistic chemopreventive effects of nobiletin and atorvastatin on colon carcinogenesis.

Different cancer chemopreventive agents may act synergistically and their combination may produce enhanced protective effects against carcinogenesis than each individual agent alone. Herein, we investigated the chemopreventive effects of nobiletin (NBT, a citrus polymethoxyflavone) and atorvastatin (ATST, a lipid-lowering drug) in colon cancer cells/macrophages and an azoxymethane (AOM)-induced colon carcinogenesis rat model. The results demonstrated that co-treatments of NBT/ATST produced enhanced growth inhibitory and anti-inflammatory effects on the colon cancer cells and macrophages, respectively. Isobologram analysis confirmed that these interactions between NBT and ATST were synergistic. NBT/ATST co-treatment also synergistically induced extensive cell cycle arrest and apoptosis in colon cancer cells. Oral administration of NBT (0.1%, w/w in diet) or ATST (0.04%, w/w in diet) significantly decreased colonic tumor incidence and multiplicity in AOM-treated rats. Most importantly, co-treatment of NBT/ATST at their half doses (0.05% NBT + 0.02% ATST, w/w in diet) resulted in even stronger inhibitory effects on colonic tumor incidence and multiplicity than did NBT or ATST alone at higher doses. Statistical analysis confirmed that the enhanced chemopreventive activities against colon carcinogenesis in rats by the NBT/ATST combination were highly synergistic. Our results further demonstrated that NBT/ATST co-treatment profoundly modulated key cellular signaling regulators associated with inflammation, cell proliferation, cell cycle progression, apoptosis, angiogenesis and metastasis in the colon of AOM-treated rats. In conclusion, for the first time, our results demonstrated a strong synergy in inhibiting colon carcinogenesis produced by the co-treatment of NBT and ATST, which provided a scientific basis for using NBT in combination with ATST for colon cancer chemoprevention in humans.

Identification of terpenoids from Rubus corchorifolius L. f. leaves and their anti-proliferative effects on human cancer cells.

The leaves of Rubus corchorifolius L. f. have been consumed as a herbal tea for a long time. In this study, two novel (1 and 5) and four known (2, 3, 4 and 6) terpenoids were isolated from the leaves of Rubus corchorifolius L. f. Structural analysis was performed using various spectroscopic methods (1H NMR, 13C NMR and MS) to identify the following six compounds: (16α)-16,17,18-trihydroxy-ent-kauran-18-O-ß-d-glucoside (1), ent-16ß,17-dialkyl-3-oxygen-kaurane (2), ent-kaurane-3α,16ß,17-triol (3), ent-kaurane(5R,8S,9R,10R,13R,16R)-2-one-16α,17-diol (4), (16R)-16ß,17,19-trihydroxy-ent-kaur-3-one (5) and ent-16α,17-dihydroxy-kauran-19-oic-acid (6). These compounds showed different inhibitory effects on various human cancer cells. Compounds 3 and 6 exhibited stronger inhibitory effects on human colon cancer HCT116 cells than the other 4 compounds. Flow cytometry analysis demonstrated that both compounds 3 and 6 caused cell cycle arrest at the G0/G1 phase and induced cellular apoptosis in HCT116 cells. Compounds 3 and 6 modulated the expression levels of key signaling proteins closely related to cell proliferation and apoptosis, i.e., increasing the levels of poly(ADP-ribose) polymerase, p53, and p27, and decreasing the levels of EGFR, cyclin D1, CDK2 and CDK4. Overall, our findings provided insight into the anticancer components of Rubus corchorifolius L. f. leaves, which could facilitate their utilization as functional food ingredients.

Stereoisomers of Astaxanthin Inhibit Human Colon Cancer Cell Growth by Inducing G2/M Cell Cycle Arrest and Apoptosis.

Astaxanthin (AST) is a xanthophyll carotenoid with potential protective effects against carcinogenesis. Different stereoisomers of AST (ASTs) exist in a variety of food sources. Due to limited information on the bioactivities of ASTs, the present study investigated the inhibitory effects of ASTs on HCT116 and HT29 human colon cancer cells. ASTs investigated herein included 3S,3'S (S) from Haematococcus pluvialis, 3R,3'R (R) from Phaffia rhodozyma, and a statistical mixture (S: meso: R = 1:2:1) (M) from synthetic AST. Cell viability assay showed that ASTs all inhibited colon cancer cell growth in a time-dependent (24-72 h) and dose-dependent (4-16 µM) manner, and there was no significant difference among the IC50 values of ASTs (p > 0.05). Flow cytometry analysis indicated that ASTs induced G2/M cell cycle arrest and cellular apoptosis in cancer cells. The cell cycle arrest caused by ASTs was associated with increases in the expression levels of p21Cip1/Waf1, p27, and p53, as well as decreases in the levels of CDK4 and CDK6. Meanwhile, the apoptosis induced by ASTs was confirmed by activation of caspase-3 and PARP in the cancer cells. The results indicated that hydroxyl (OH) at C3 and C3' of terminal ring structure might not be the major factor that affects the anticancer activity of AST. This study revealed important information on the inhibitory effects of ASTs on human colon cancer cells, which provided a basis for using ASTs as chemopreventive agents for colon cancer.