Health effects of subchronic intake of high-dose Dendrobium officinale in rats / 预防医学

Objective@#To assess the effects of subchronic intake of high-dose Dendrobium officinale on body weight, food intake, food utilization, and blood biochemical parameters in rats, so as to provide insights into assessment of edible safety of D. officinale.@*Methods@#Eighty SPF-grade SD rats were randomly divided into the low-, medium- and high-dose groups and the control group, of 10 male and 10 female rats in each group. Rats in the low-, medium- and high-dose groups were administered with D. officinale feeds at doses of 2.0, 4.0, and 8.0 g/kg body weight, respectively, while animals in the control group were given basic diet for successive 13 weeks. The rat body weight, food intake, food utilization, and blood biochemical parameters were compared between groups.@*Results@#Normal diet and activity was seen in all rats, and no abnormal syndromes, signs or deaths were found during the study. There were no significant differences in rat body weight, food intake, total weight gain, total food intake, alanine aminotransferase, aspartate aminotransferase, urea nitrogen, creatinine, triacylglycerol, cholesterol, total protein, albumin, albumin/globulin ratio or blood glucose among four groups (P>0.05). The food utilization 7 weeks post-administration [(8.71%±0.78%) vs. (10.54%±1.37%), P<0.05] and the total food utilization [(18.00%±0.41%) vs. (19.51%±1.21%), P<0.05] were significantly lower in male rats in the high-dose group than in the control group.@*Conclusion@#Subchronic intake of high-dose D. officinale shows no toxicity in rats, and reduced food utilization may be associated with the health function of D. officinale in male rats.

Use of different endpoints to determine the bioavailability of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in Sprague-Dawley rats.

Liver, fat (adipose tissue), blood, and feces are common endpoints used to determine the bioavailability of persistent organic pollutants (POPs). However, it is not known whether the bioavailability of each endpoints is comparable or whether there is a comprehensive endpoint that can be used for all congeners for the measurement of bioavailability. In this study, we observed the accumulation and distribution of 10 polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and 18 polychlorinated biphenyls (PCBs) in different organs of Sprague-Dawley (SD) rats and calculated the bioavailability based on feces, liver, and fat endpoints. Our results indicated that PCB 126, PCB 169, and 50% of PCDD/F congeners were mainly accumulated in the liver, with a bioavailability ranging from 28.9 to 50.6%. On the other hand, higher chlorinated (> 5 Cl) PCB congeners were mainly accumulated in adipose tissues, with a bioavailability ranging from 20.1 to 82.2%, while lower chlorinated (< 5 Cl) pollutants, such as 2,3,7,8-TeCDF, 2,3,7,8-TeCDD, 1,2,3,7,8-PeCDF, and PCB 28, 52, 77, 81, were likely metabolized over 36% in rats during the 8-week experimental period. If we considered metabolization (degradation) as a type of bioavailable process, then the fecal endpoint was a feasible option. However, if we considered the selective accumulation behavior of some congeners in different organs/tissues, then there was no single comprehensive endpoint suitable for all congeners. Lastly, female rats showed significantly higher PCDD bioavailability than male rats at low dose level (0.2 ng/100 g b.w./d); however, the difference in PCB bioavailability between female and male rats was not significant.

Skin damage caused by sunlight ultraviolet in mice / 预防医学

Objective @#To study the damage effect of sunlight ultraviolet exposure on skin.@*Methods @#No exposure group, low exposure group and high exposure group were set up with 10 mice in each. The exposure doses of sunlight ultraviolet were 0, 10 J/cm2 and 20 J/cm2, respectively. The skin of mice was irradiated by a sunlight ultraviolet simulator for 5 days a week, 13 weeks. At the end of the experiment, the skin appearance of mice was examined; the skin moisture, oil content, texture density, hydroxyproline ( HYP ), hyaluronic acid (HA), malondialdehyde ( MDA ), glutathione ( GSH ) and superoxide dismutase ( SOD ) activities were detected; and the skin tissue morphology, collagen fiber morphology and elastic fiber morphology were observed. @*Results @#The skin appearance of mice in the no exposure group was normal; in the low exposure group, only one mouse had mild skin desquamation; in the high exposure group, the skin was loose and wrinkled, dry and desquamated, local thickening and erythema formation. Compared with the no exposure group, the contents of skin moisture, HYP, HA and SOD activity were lower, texture density, MDA content, morphological scores of skin tissue, collagen fiber tissue and elastic fiber tissue were higher in the high exposure group ( all P<0.05 ). Compared with the low exposure group, the HA content and SOD activity were lower, the skin texture density, MDA content, and histomorphological scores of skin tissue and collagen fibers were higher in the high exposure group ( all P<0.05 ).@*Conclusion @#Exposure to 20 J/cm2 sunlight ultraviolet can significantly lead to abnormal skin appearance and function in mice.

Effects of curcumin on the bioavailability of dioxin-like pollutants in rats.

The effects of curcumin on the bioavailability of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) were investigated in Sprague-Dawley rats. Tetra- and penta-chlorinated PCDFs had the lowest bioavailability and hexa-chlorinated PCDD/Fs had the highest, while there was no obvious change in that of DL-PCBs. Curcumin markedly reduced the toxic equivalent (TEQ) of PCDD/Fs in rats, illustrating the potential to competitively inhibit absorption of PCDD/Fs by the epithelial cells of the small intestine due to the similar chemical structure (diphenyl) between curcumin and PCDD/Fs. Moreover, curcumin lowered the TEQ of DL-PCBs in the liver of male rats, but not female rats. The significant decrease in the bioavailability of PCDD/Fs and DL-PCBs demonstrates the potential detoxification mechanisms of curcumin.

Effects of 5-HMF on glycolipid metabolism and hepatic function in mice with diabetes and hepatic injury / 预防医学

Objective@#To observe the effect of 5-hudroxymethyl-2-furfural (5-HMF) on glycolipid metabolism and hepatic function in mice with type 2 diabetes mellitus (T2DM) and hepatic injury. @*Methods@#A low, a medium and a high 5-HMF dose group, a model group, and a control group were designed, with ten female ICR mice in each group. The low, medium and high dose group were given 0.27, 0.80 and 2.67 mg/kgbw 5-HMF, respectively, for 12 weeks; while the model group and the control group were given volume controlled deionized water. The model group and three dose groups were fed with high-fat and high-sugar food (36%), and the intraperitoneal injection of alloxan (60 mg/kgbw) was executed in the 10th and 11th week; the control group were fed with normal food. The body weight, blood glucose, blood lipid, and liver function of mice were determined regularly. The livers were stained by periodic acid Schiff and the changes in pathology were observed. @*Results@#Compared with the control group, the serum levels of glucose (GLU), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) were significantly higher in the model group (P<0.05). Compared with the model group, the AST level in the low and high 5-HMF dose group, and the LDH level in the low, medium and high 5-HMF dose group, were significantly lower (P<0.05). There were no significant differences in the levels of GLU, total cholesterol, LDL-C, triacylglycerol, HDL-C and ALT between the model group and the three dose groups (P>0.05). Moderate to severe vacuolar degeneration was observed in the model group, while mild vacuolar degeneration was observed in the high dose group. Medium or large amount of hepatic glycogen granules were observed in the high dose group and the model group. @*Conclusion@#Under the conditions of this experiment, 5-HMF does not show any obvious function of reducing blood glucose and lipid in the mice with T2DM and liver injury, but show some protective effects on liver function．

Effects of Lycium barbarum polysaccharides on blood indexes andliver tissue morphology in rats with intrahepatic cholestasis / 预防医学

Objective@#To study the effects of Lycium barbarum polysaccharides ( LBP ) on blood indexes and liver tissue morphology in rats with intrahepatic cholestasis.@*Methods@#Sprague-Dawley rats were randomly divided into the control group, the model group, and LBP low, medium and high dose group. The rats in the model group and LBP dose groups were given 60 mg/kg alpha-naphthylisothiocyanate ( ANIT ) by gavage every three days of the experiment, and the rats in the control group were given salad oil instead of ANIT. From the third day, the rats in each dose group were given 40, 150 and 600 mg/kg LBP, and the rats in the model group were given distilled water. After four weeks, the blood and urine indexes were measured, and the morphological changes of liver tissue were observed. @*Results@#From the third day of the experiment, the activity of rats in the model group and LBP dose groups decreased, and the color of urine changed to dark yellow. There was no abnormality in the group. In the model group, the levels of serum total bilirubin, direct bilirubin, total bile acid ( TBA ), alkaline phosphatase ( ALP ), γ-glutamyltransferase(γ-GGT), cholesterol, alanine aminotransferase ( ALT ), aspartate aminotransferase ( AST ), white blood cell ( WBC ), percentage of granulocyte, urinary bilirubin, urinary bile acid, liver mass and liver to body ratio were higher than those in the control group, while red blood cell and percentage of lymphocyte were lower than those in the control group ( all P<0.05 ). Pathological changes of liver tissue were observed. The levels of serum TBA, ALP, γ-GGT, ALT, AST, WBC and liver to body ratio in LBP high dose group were lower than those in the model group ( all P<0.05 ). The infiltration of inflammatory cells, proliferation and expansion of bile duct, degeneration and necrosis of liver cells were alleviated. @*Conclusions@#LBP can improve the blood indexes and pathological changes of liver tissue in rats with intrahepatic cholestasis at the dosage of 600 mg/kg. Inhibition of inflammatory response and reduction of oxidative stress injury may be the mechanism for alleviating cholestatic liver injury.

Toxicity of Dendrobium officinale flowers to pregnantrats and offspring rats before birth / 预防医学

Objective@#To learn the toxicity of Dendrobium officinale flowers to pregnant rats ( P, F1 ) and offspring rats ( F1, F2 ) before birth, so as to provide toxicological evidence for the safety assessment.@*Methods @#The rats were divided into four groups with 20 female rats and 10 male each. The rats in three dose groups were fed with Dendrobium officinale flowers at the dose of 2.0, 4.0, 6.4g/kgbw. After two generation, the F1a and F2a rats were fed with basal diet; F1b and F2b rats were fed with Dendrobium officinale flowers. The body weights and total weight gains during the gestation, the conception rates, the pregnancy rates, the birth weights and survival rates of offspring rats were examined. @* Results@#There were no statistically significant differences in the body weights and total weight gains during the gestation, the conception rates, and the pregnancy rates in pregnant rats ( P, F1 ) among the four groups ( P>0.05 ). There were also no statistically significant differences in the survival rates and live birth rates in offspring rats (F1, F2) between the dose groups and the control group ( P>0.05 ). @*Conclusions@#Dendrobium officinale flowers did not show obviously adverse effects on pregnant rats ( P, F1 ) and offspring rats ( F1, F2 ) before birth.

Simultaneous detection of multiple hydroxylated polychlorinated biphenyls from biological samples using ultra-high-performance liquid chromatography with isotope dilution tandem mass spectrometry.

We established a method for the separation and detection of nine hydroxylated polychlorinated biphenyls in whole blood and urine samples using ultra high performance liquid chromatography coupled with electrospray negative ionization tandem mass spectrometry. Clean-up procedures involved a filtration step, and optimization involved a pretreatment step consisting of a simple liquid-liquid extraction using hydrated silica-gel chromatography (5%). Nine hydroxylated polychlorinated biphenyls were separated on an ultra high performance liquid chromatography HSS T3 column using a gradient elution program of 2 mmol ammonium formate aqueous solution (A) and methanol (B). Recovery ranged from 84.0 to 105.4% for the nine different hydroxylated polychlorinated biphenyls in urine with three spiked levels of 0.1, 1, and 2 ng and from 73.5 to 98.6% for the blood with spiked levels of 0.2, 1, and 2 ng. The relative standard deviations were <8.7% (n = 6), and the limits of detection in urine and whole blood for the nine hydroxylated polychlorinated biphenyls were in the range of 1.5-4 and 20-100 pg/g, respectively. This analytical method may enable the simultaneous detection of various hydroxylated polychlorinated biphenyls from complex tissue matrices.

[Toxicity of intragastrically administered N, N-dimethylformamide in female Wistar rats].

OBJECTIVE: To investigate the toxicity of intragastrically administered N, N-dimethylformamide (DMF) in female Wistar rats, and to provide experimental data for the overall evaluation of DMF toxicity under different ways of exposure. METHODS: Forty female Wistar rats weighing 150∼180 g were randomly divided into four groups: control group (treated with water) and three DMF exposure groups with doses of 50 mg/kg, 100 mg/kg, and 200 mg/kg. After oral administration of DMF once a day for 14 consecutive days, the rats were weighed and sacrificed. The liver, kidney, brain, and uterus were weighed to calculate organ indices. The pathological changes in the liver were examined by HE staining. The protein expression of HSP70 in the liver, kidney, and brain was determined. Finally, peripheral lymphocytes were collected from the arteria cruralis to determine DNA damage by comet assay. RESULTS: Fourteen days after DMF exposure, the body weight and organ indices of the kidney, brain, and uterus showed no significant changes. However, the liver index showed concentration-dependent increase in all DMF exposed groups (3.52±0.21, 3.55±0.13, and 3.88±0.22 in the low-, medium-, and high-dose groups, respectively), as compared with the control group (3.24±0.28) (P < 0.05 or P < 0.01). The pathological damage in the liver also showed a concentration-dependent manner. Inflammatory cell infiltration and granular degeneration in centrilobular hepatocytes were observed in the high-dose group. No significant change in protein expression of HSP70 was observed in the liver, kidney, or brain of DMF-exposed rats (P > 0.05). DNA damage was induced by DMF, and the DNA percentage of lymphocyte comet tail, average tail length, and tail moment in exposed groups were all significantly increased as compared with the control group (P < 0.05 or P < 0.01). CONCLUSION: Gavaged DMF can induce liver injury and DNA damage in lymphocytes in rats 14 days after administration. There is no significant change in protein expression of HSP70 in the liver, brain, or kidney after DMF exposure.

[Oxidative damage and immunotoxicity effect of people who exposed to electronic waste].

OBJECTIVE: To investigate the relationship between risk factors and the effects of antioxidation and immune function in adults who exposed to electronic waste( e-waste). METHODS: The exposed group was chosen from the people who lived in the e-waste disposing areas of Zhejiang province. The control group was chosen from people who lived in unpolluted area. Anticoagulation and coagulation peripheral venous blood samples were collected from 40 exposed persons (22 employees, 18 non-employees) and 36 exposed persons respectively. The oxidative, immune, Cd, Pb, Cr, Hg, and PCB indexes were detected. RESULTS: The contents of Cd, total PCB, MDA statistically increased in exposed group comparing with the control group (P < 0.05). The activity of SOD, GSH-Px, the percentage of helper/inducer T lymphocytes (CD4+) and the content of Cr in exposed group were less than those in the controlgroup (P < 0.05). CONCLUSION: Oxidative damage and immunotoxicity were observed in the group that lived in e-waste disposing areas. These effects were mainly related to the increase of Cd content or Cd and Pb contents in peripheral venous blood.

Health risk assessment of lead for children in tinfoil manufacturing and e-waste recycling areas of Zhejiang Province, China.

Tinfoil manufacturing and electronic waste (e-waste) recycling remain rudimentary processes in Zhejing Province, China, which could account for elevated blood lead levels (BLLs) and health impacts on children. We assessed the potential health risks of lead in tinfoil manufacturing and e-waste recycling areas. 329 children in total aged 11-12 who lived in a tinfoil manufacturing area (Lanxi), an e-waste recycling area (Luqiao) and a reference area (Chun'an) were studied. Lead levels in children's blood were determined by inductively coupled plasma mass spectrometer (ICP-MS). Blood urea nitrogen (BUN), serum creatinine, serum calcium, δ-Aminolaevulinic acid (δ-ALA) and intelligence quotient (IQ) were also measured. Geometric mean of BLLs in Lanxi, Luqiao and Chun'an were 8.11 µg/dL, 6.97 µg/dL, and 2.78 µg/dL respectively, with 35.1%, 38.9% and 0% of children who had BLLs above 10 µg/dL. The BLLs in exposed areas were much higher than those in the control area. Lanxi children had higher creatinine and calcium than Chun'an children, and Luqiao children had higher δ-ALA and lower calcium than Chun'an children. No significant differences of IQ were observed between Lanxi, Luqiao and Chun'an, however a negative relationship between BLLs and IQ was shown for the study children. The results indicated that lead pollution from e-waste recycling and tinfoil processing appears to be a potential serious threat to children's health.

[Study on contamimation of endocrine disrupting chemicals in aquatic environment of Qiantang River].

OBJECTIVE: To study contamination of endocrine disrupting chemicals (EDCs) in aquatic environment of Qiantang River. METHODS: Carp vitellogenin (VTG) content in serum and ethoxyresorufin-o-deethylase (EROD) activity in liver of wild crucian, pesticide content including organic cholorine, organic phosphorus and pyrethroid in its muscle from 7 monitoring sites including Zhangtan (ZT), Jiekou (JK), Jiangjunyan (JJY), Yandongguan (YDG), Tonglu (TL), Fuyang (FY) and Yuanpu (YP) in Qiantang river were detected. And chemical analysis of water quality was carried on in four sites. RESULTS: EROD activity in crucian from ZT, JJY, FY and YP [(23.51 +/- 4.17), (16.79 +/- 7.39), (18.74 +/- 5.16), (18.65 +/- 8.86) nmol x g(-1) pro x min(-1), respectively] was significantly higher than that of control ((7.84 +/- 2.42) nmol x g(-1) pro x min(-1)), and VTG content in wild crucian from ZT, TL, FY and YP [(1.536 +/- 0.521), (16.404 +/- 13.579), (19.672 +/- 16.354) and (17.079 +/- 18.397)] microg/ml, respectively) was significantly higher than that of control [(0.400 +/- 0.099) (microg/ ml]. No significantly difference in biomarkers was observed between other site and control. From high to low, in total organophosphorus, it was followed as: TL, YDG, YP, FY, QZ, JK, JJY (EPN was up to 2695.64, 611.96 microg/kg in TL and YDG, respectively). In total organochlorine: TL, YP, YDG, FY, QZ, JK and JJY (tetradifon content in muscle of wild crucian from TL was up to 3962.17 microg/kg). For pyrethroid pesticides: TL, YDG, YP, ZT, JK, FY and JJY (alpha-tetramethrin and alpha-phenothrin was comparatively high in TL and YDG, up to 371.54, 239.62 microg/kg in the former, 416.23, 189.15 microg/kg in the latter, respectively). CONCLUSION: Aquatic environment of these sites including ZT, TL, FY and YP in Qiantang river received comparatively high EDCs, whose effects may be mainly due to pesticide pollution. Obvious organic contamination occurred in these sites including ZT, JJY, FY and YP. Changes of chemicals in water and EROD activity in fish test result are consistent with the actual contamination, while agricultural effluent discharges only affect the local River in the downstream. High PAH contamination in these sites such as ZT maybe lead to underestimation of estrogen effects, which was neglected easily, need be paid more attention to.

Distribution of PCDD/Fs, PCBs, PBDEs and organochlorine residues in children's blood from Zhejiang, China.

Concentrations and congener specific profiles of PCDD/Fs, PCBs, PBDEs and organochlorine residues were measured in 22 pooled blood samples representing 66 children from both polluted areas (E-waste recycling region) and case control areas in Zhejiang province, China. To our knowledge, this is the first report on these pollutants in the blood of Chinese children. The mean concentrations of [summation operator]PCDD/Fs, [summation operator]PCBs, [summation operator]PBDEs, HCB and pp'-DDE in pooled blood samples from polluted areas (Luqiao) were 206+/-157 pg g(-1) lipid, 40.6+/-7.01 ng g(-1) lipid, 32.1+/-17.5 ng g(-1) lipid, 14.6+/-20.1 ng g(-1) lipid and 108+/-21.8 ng g(-1) lipid, respectively. WHO-TEQ-2005 for PCBs and PCDD/Fs were 11.9+/-4.62 pg g(-1) lipid and 10.3+/-6.39 pg g(-1) lipid, respectively. The results showed that PCBs, PBDEs and organochlorine residues in the E-waste recycling area were significantly (P<0.001) higher than the case control areas. High levels of PCDD/Fs were detected in the case control area (Longyou), where Na-PCP had been widely sprayed to prevent snailborne schistosomiasis. The contamination levels and profiles were compared with those documented in previous publications.