Search

Objective: To observe the steatosis and inflammatory effects of L02 hepatocytes induced by different concentrations of sodium oleate., Methods: L02 cells were incubated with sodium oleate in different concentration for 24 h, and the cell viability was detected. L02 cells were respectively cultured with 75, 150, 300 μmol/L sodium oleate for 24 h. The lipid accumulation of the cells was observed by oil red staining. The content of triglyceride in the cells was detected, the IL-6 content in the cell supernatant was detected. The expression of SIRT1 and nuclear factor-κB(NF-κB) was detected by Western Blot. The expression of Toll-like receptor 2 and Toll-like receptor 4(TLR2 and TLR4) on the cell surface was detected by flow cytometry., Results: With the increase of sodium oleate concentration, the cell viability decreased, the cell growth inhibition rate increased. The content of triglyceride in L02 cells treated with 75, 150 and 300 μmol/L sodium oleate was significantly higher than that in the control group(P<0. 01, P<0. 001, P<0. 001), the IL-6 in the supernate was significantly higher than that in the control group(P<0. 05, P<0. 01, P<0. 001). The result of oil red staining showed that the lipids in the cells were obviously accumulated after sodium oleate treatment. The expression of TLR2 in L02 cells treated with 150 and 300 μmol/L sodium oleate was significantly higher than that in the control group(P<0. 05, P<0. 001). There was no significant increase in TLR4 expression after sodium oleate intervention in L02 cells. The expression of SIRT1 protein in the sodium oleate group was lower than that in the control group, and the expression of NF-κB p65 was higher than that in the control group through Western Blot result., Conclusion: L02 hepatocyte steatosis caused by sodium oleate may be associated with TLR2/NF-κB mediated inflammatory pathway.

Objective: To establish an rat basophil leukemia(RBL)-2H3 cell line stably expressing human high affinity receptor containing alpha, beta and gamma chain(hFcεRIαβγ), in order to provide experimental materials for evaluating allergenicity of food., Methods: The lentivirus was transfected into RBL-2H3 cells, and the mRNA expression of hFcεRIαβγ in cells was detected by real-time PCR and the protein expression of hFcεRIα was detected by flow cytometry., Results: Sequencing result showed that recombinant lentiviral vector GV367-hFcεRIαβγ was successfully constructed. According to the result of experiments, lentivirus could effectively infect RBL-2H3 cells. The mRNA of hFcεRIαβγ and protein levels of hFcεRIα in RBL-2H3 cells were successfully overexpressed., Conclusion: The hFcεRIαβγ/RBL-2H3 cells were preliminarily constructed, which could be binded with human IgE and further used in the evaluation system of food allergy, compared to RBL-2H3 cells.

Objective: To systematically review the nutritional effect of YYB on infants and young children in poor rural regions., Methods: Medline, PubMed, Cochrane Library, CNKI and other sources of nutrition and health information were retrieved with the predetermined key words. The quality of the obtained literatures was evaluated with the criteria established in this study. RveMan 5.3 was used in the meta analysis., Results: Thirteen groups of qualified data from nine YYB intervention studies were used. The results showed that YYB significantly increased the level of Hb (MD = 0.94, 95% CI 0.94-1.15, P < 0.01), reduced the prevalence of anemia (RR = 0.34, 95% CI 0.25-0.46, P < 0.01). YYB showed no significant effect on WAZ and HAZ, but significant increase of WHZ was demonstrated by the analytical data (MD = 0.42, 95% CI 0.19-0.65, P < 0.01). Additionally YYB intervention groups also showed the prevalence of underweight (RR = 0.53, 95% CI 0.32-0.88, P < 0.05)., Conclusion: As an infant complementary food supplement, YYB improved the nutrition status of infants and young children including increased Hb level, declined anemia prevalence and wasting rate.

Objective: To explore the effect of vitamin E (VE) and selenium (Se) deficiency on esophageal tumorigenesis and its oxidative stress mechanism., Methods: 110 male F344 rats were randomly divided into 3 groups: VE/Se deficient group (group A), VE/Se normal group (group B) and control group (group C). Animals in group A and group B were subcutaneously injected with N-nitrosomethylbenzylamine (NMBzA) at the dosage of 0.35 mg/kg BW, 3 times per week for 5 weeks. Control group was given the solvent 20% DMSO as negative control. Animals in group A were fed with low-VE/Se diet (46IU/kg VE, 0.05 mg/kg Se), animals in group B and C were fed with normal diet (80IU/kg VE, 0.15 mg/kg Se). Animals were sacrificed to perform macroscopic observation and pathologic inspection at the 25th week of the experiment. Plasma VE level was determined by high-performance liquid chromatography, and Se level was determined by fluorescence method. Cell proliferation and DNA damage in esophagus were detected through immunohistochemistry of BrdU and 8-OH-dG, respectively. Glutathione peroxidase (GPX) and glutathione transferase (GST) activities in plasma, esophagus and liver were analyzed by using test kits., Results: VE/Se levels of group A were significantly lower than those of group B, the later were slightly lower than those of group C. Visible tumor incidence, tumor multiplicity and pathologic lesions in group A were all significantly more than those in group B. Comparing with group B, cell proliferation and 8-OH-dG levels were also significantly increased in group A. GPX and GST activities in plasma, esophagus and liver of group A were significantly higher than those of group B., Conclusion: Vitamin E and selenium deficiency significantly promoted the NMBzA-induced esophageal tumorigenesis. Oxidative stress and DNA damage may be one of the critical routes by which NMBzA induces carcinogenesis in rat esophagus.

Objective: To study the potential endocrine disrupting effects of bifenthrin (BIF) by using uterotrophic assay and Hershberger assay., Methods: In uterotrophic assay, 60 female SD rats were randomly divided into 6 groups, 10 rats per group. Rats in bifenthrin-treated groups were given different doses of bifenthrin (1.47, 4.41 and 13.23 mg/kg BW by gavage for 3 consecutive days). Rats in negative control groups were given corn oil by gavage. Rats in ethinyl estradiol (EE) oral positive control groups were given EE 1.0 microg/kg BW by gavage. Rats in EE injected positive groups were given 0.6 microg/kg BW EE by subcutaneously injection while given corn oil by gavage. At necropsy, the wet and blotted uteri were weighed. The relative uteri weights were calculated, and the histology of uteri was observed. In Hershberger assay, 60 castrated male SD rats were randomly divided into 6 groups, with 10 rats in each group. Rats in BIF-treated groups were given different doses of BIF (1.4, 4.2 and 12.6 mg/kg BW) by gavage. Flutamide (3.0 mg/kg BW) were given to animals in the positive control group by gavage. Rats in the negative control group and testosterone propionate group were given corn oil by gavage for 10 consecutive days. Rats in all groups except the negative control group were also treated with testosterone propionate (TP, 0.2 mg/kg BW) by subcutaneous injection. At necropsy, ventral prostate (VP), seminal vesicle plus fluids and coagulating glands (SVCG), levator ani-bulbocavernosus muscle (LABC), paired Cowper's glands (COW) and the glands penis (GP), liver, kidneys, adrenals were weighed. Serum triiodothyronine (T3) and thyroxine (T4) were determined., Results: In uterotrophic assay, compared with the negative control group, the mean relative wet weight and relative blotted weight of uterine were increased significantly in the female rats given by BIF at 13.23 mg/kg BW for 3 days (P < 0.05). BIF resulted in a significant increase of epithelial cell heights of uteri at 4.41 and 13.23 mg/kg BW, as compared with control group. In Hershberger assay, compared with the TP group, mean absolute weight and relative weight of VP and LABC in BIF high dose group were significant decreased. Moreover, total T3 and T4 level were decreased also (P < 0.05)., Conclusion: Uterotrophic assay and Hershberger assay used in this study showed that BIF may have endocrine disrupting properties.

Objective: To establish a BN rat model for testing food allergenicity., Methods: BN rats of both sex and aged 4 and 8 weeks were exposed to different doses of ovalbumin (OVA) (1.00 mg, 0.10 mg and 0.01 mg) by intraperitoneal injection on the 1st, 5th and 10th day of the study and observed for 35 days. Blood samples were taken on the 28th and 35th day of the study from orbital plexus and serum specific IgE (OVA sIgE) were determined by ELISA., Results: Compared with the control group, the concentrations of OVA sIgE of 8-week female BN rats on the 28th and 35th day were significantly increased when 1.00 mg and 0.10 mg OVA was applied (P < 0.05). The concentrations of OVA sIgE of 8-week male BN rats on the 28th day were significantly higher than that in the control group when 0.10 mg and 0.01 mg OVA was applied (P < 0.05). And the concentrations of OVA sIgE of 8-week male BN rats on the 35th day were significantly higher than that in the control group when 1.00 mg OVA was applied (P < 0.05). The concentrations of OVA sIgE of 4-week male BN rats on the 35th day were significantly higher than the control group when 1.00 mg OVA was applied (P < 0.05)., Conclusion: Female rats were more sensitive than male rats to different doses of OVA administered intraperitoneally; 8-week rats were more sensitive than 4-week rats; the better dose of OVA for sensitizing BN rats was 0.10 mg or 1.00 mg. Therefore, an ideally sensitized animal model could be established by administering 8-week female BN rats with 0.10 mg or 1.00 mg OVA intraperitoneally in 35 days later.

Objective: To study the feasibility of C3H/HeJ mice as the food allergenicity rodent model and explore the appropriate period of two different routes of exposure and the change of helper T lymphocyte cell., Methods: Allergenic protein ovalbumin (OVA) was administered intraperitoneally or orally to female C3H/HeJ mice for 35 days. Blood samples were taken on the 14th, 28th and 35th days from the orbital plexus and sera were obtained to determine OVA specific IgE (OVA sIgE). Spleen samples were obtained on the 35th day to detect the mRNA expression of Th2-type cytokines IL-4 and Th1-type cytokines IFN-gamma by real-time RT-PCR., Results: Compared with the control group, the concentration of OVA sIgE on 28th and 35th days were significantly increased in OVA group by gavage (P < 0.05). The concentration of OVA sIgE on 14th, 28th and 35th days were significantly higher than the control group when OVA was given intraperitoneally (P < 0.05). Compared with the control group, the mRNA expression of IL-4 of OVA group and OVA + Al(OH)3 group were significantly increased. The mRNA expression of IFN-gamma of OVA group and OVA + Al(OH) group were significantly lower than the control group., Conclusion: C3H/HeJ mice might be used as a rodent model for the assessment of allergenicity of food. The appropriate period is the 14th day for the route of intraperitoneal injection and the 28th day for oral gavage, respectively.

Objective: Protein allergenicity was investigated in BN rat model., Methods: OVA or BSA was administered i.p. (1 mg/ml) or orally (10 mg/ml) to male BN rats for 6 weeks. In different intervals, blood samples were obtained from the orbital plexus for PCA and histamine determination. In addition, blood pressure of rats in OVA-treated group and control group was measured., Results: Relatively high titres (1/32-1/128) IgE responses were provoked by administration of OVA, while BSA stimulated only low titres (1/2-1/4) IgE. Compared with the controls, the plasma histamine concentrations of OVA groups were higher. An oral challenge with OVA did not induce a clear effect on blood pressure in the majority of rats. However, two rats demonstrated a temporary drop in blood pressure., Conclusion: BN rat model may be a suitable animal model to determine protein allergenicity.

The present study was to investigate the chemopreventive effects of tea pigments. In vitro study showed that tea pigments induced QR activity and GST activity in Hep G2 cells. Three animal models were used to observe the preventive effects of tea pigments on liver cancer, colorectal cancer and oral cancer. Oral administration of 0.1% tea pigments increased GST activity in rat liver by 18%, and this increase was accompanied by the significant increase of GST 1-1, 1-2, and 3-3 protein expression in rat liver. Tea pigments inhibited the proliferating cell nuclear antigen labeling index (PCNA-LI), the expression of Bcl-2 protein and ras-p21 protein, and induced the expression of Bax protein in rat colorectal cancer. PCNA-LI, silver-stained nucleolar organizer regions (AgNOR) and epidermal growth factor receptor (EGFR) expression were also inhibited by tea pigments in hamster oral cancer. Our results suggested that tea pigments had chemopreventive effects on cancer, and the anti-cancer properties may be due to the activation of detoxifying enzymes such as QR and GST, the inhibition of cell proliferation and the induction of apoptosis.

Toxicological effect of 3-chloro-1,2-propanediol on rats were studied to provide scientific basis for assessing the effect of Chloropropanols on human health. 170 SD rats were divided randomly into 8 groups and the dose of 0, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0, 16.0 mg/kg 3-chloro-1,2-propanediol were given to rats for 90 days by gavages per day, respectively. The weight and food efficiency, hematology and clinical chemistry, NAG, GGT and total protein in urine, sperm number, sperm survive rate and sperm aberration rate, the LDH and LDH-X activity in testis, rate of organ/weight and histopathological analysis were measured. The results showed that different dose of 3-chloro-1,2-propanediol did not has adverse effect on body weight, food efficiency, Hb, red cell, white cell, serum AST, ALT, creatine, ALP, LDH, total protein and albumin, urine GGT and total protein, LDH activity in testis. At the dose of 4.0, 8.0 and 16.0 mg/kg group, the activity of NAG in urine and the rate of kidney/weight was significantly increased compared with negative control groups; the pathological changes in kidney were observed in the same groups, and the sperm number was also significantly decreased. At the dose of 8.0 and 16.0 mg/kg group, sperm survive rate and the X-LDH activity were significantly decreased and pathological changes were also observed in testis and caudal epididymis. It was concluded that the activity of NAG in urine and sperm number is the sensitive biological effective marker. Because urine is a kind of convenient available biological material, NAG activity in urine is a good biological effective marker for assessing effect of Chloropropanols on health. If the NAG activity can be used as sensitive marker for assessment on human health need to be tested further in human study.

The effects of tea polyphenols and tea pigments on cell cycle of hepatic cancer cells were studied. HepG2 cells were incubated with 50 and 100 mg/L tea polyphenols and tea pigments for 48 h respectively. Flow cytometry, Western blot and RT-PCR analysis were used. Flow cytometry analysis showed that tea polyphenols and tea pigments induced G1 arrest. Western blot analysis showed tea polyphenols and tea pigments significantly inhibited the expression of cyclin D1 protein and induced higher expression of P21WAFI/CIPI protein. The result of RT-PCR analysis demonstrated that Cdk4 was significantly inhibited by tea polyphenols and tea pigments. It is concluded that the induction of cell cycle arrest may be an important mechanism of tea on cancer prevention.