Xudong Jia

A pilot study on the effects of almond consumption on DNA damage and oxidative stress in smokers.

Abstract: The effects of almond consumption on DNA damage and oxidative stress among cigarette smokers were studied. Thirty healthy adult male regular smokers were randomly divided into three groups, 10 subjects per group. Group A (control group) did not receive any almonds. Subjects in Groups B and C received 3 oz and 6 oz (84 g and 168 g) of almonds each day respectively for 4 wk. Two known biomarkers for DNA damage, urinary 8-hydroxy-2’-deoxyguanosine (8-OH-dG) and single strand DNA breaks of peripheral blood lymphocytes, were measured by enzyme-linked immunosorbent assay and comet assay, respectively. In addition, plasma malondialdehyde (MDA) level, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured as biomarkers for oxidative stress. The results showed lower levels of urinary 8-OH-dG and single strand DNA breaks in the two almond-treated groups as compared with the control group. Furthermore, MDA levels in the almond-treated groups were lower than the controls. However, no significant effects of almonds on SOD and GSH-Px activities were found. In conclusion, results from this pilot study indicate that almond consumption has preventive effects on oxidative stress and DNA damage caused by smoking. A larger, randomized, placebo-controlled clinical trial on almonds will be initiated in the near future.

A subchronic oral toxicity study of almond skins in rats.

Almond skins have been suggested to have some potential benefits. To investigate the subchronic toxicity of almond skins, a 90-feeding study was conducted in rats. Sprague-Dawley rats were randomly divided into four groups (20 rats/sex/group) and received a diet containing 0%, 2.5%, 5.0% and 10% (w/w) almond skins for 90 days. Daily clinical observations and weekly measurement of body weights and food consumption were conducted. Ophthalmic examinations were performed at pre-test and termination. Blood samples were obtained on day 46 and day 91 for the measurement of hematology, coagulation and clinical chemistry parameters. Urine samples were collected on day 91 for urinalysis. Animals were euthanized for necropsy. Selected organs were weighted and recorded. Histological examination was performed on all tissues from animals in the control and high-dose groups. No mortality, body weight, ophthalmic abnormalities or treatment-related findings in clinical observations, hematology, coagulation, urinalysis parameters, macroscopic or microscopic examinations were observed. Differences between treated and control groups in weight gain, food consumption, clinical chemistry, and organ weight were not considered treatment-related. The no-observed-adverse-effect-level (NOAEL) for almond skins was considered to be 10% (w/w) for both genders (females, 9.7 g/kg body weight/day; males, 8.2g/kg body weight/day).

A 90-day oral toxicity study on a new strain of Lactobacillus paracasei in rats.

Lactobacillus paracasei is a species of bacteria that has been suggested to have probiotic benefits. To investigate the subchronic toxicity of L. paracasei GW080, a 90-feeding study was conducted in rats. Sprague-Dawley rats were randomly divided into four groups (10 rats/sex/group) and treated with 0, 1.25, 2.5, and 5.0 g/kg body weight (approximately equivalent to 0, 2.5×10(9), 5.0×10(9) and 1×10(10)cfu/kg bw) of test material by gavage for 90 days. Daily clinical observations and weekly measurement of body weights and food consumption were conducted. Blood samples were obtained on day 46 and day 91 for the measurement of hematology and clinical chemistry parameters. Animals were euthanized for necropsy. Selected organs were weighted and recorded. Histological examination was performed on all tissues from animals in the control and high dose groups. No mortality, body weight, food consumption or treatment-related findings in clinical observations, macroscopic or microscopic examinations were observed. Differences between treated and control groups in some hematology and clinical chemistry parameters were not considered treatment-related. The no-observed-adverse-effect-level (NOAEL) for L. paracasei GM080 was considered to be 5.0 g/kg body weight (approximately equivalent to 1×10(10)cfu/kg bw) for both genders, the highest dose tested.

Subchronic Toxicity Study on Soy Isoflavones in Rats

OBJECTIVEnTo investigate the subchronic toxicity of soy isoflavones (SIF) in male rats.nnnMETHODnFifty Sprague-Dawley rats were randomly divided into 5 groups, 10 rats per group. SIF were given to rats in different groups by gavage at dose of 0, 0.2, 0.5, 1.5, and 4.5 g/kg bw, respectively for 13 weeks. Clinical manifestations, body weight, and food consumption were observed weekly. At the end of the study, urinalysis, hematology, clinical chemistry, total testosterone, and follicle-stimulating hormone were tested, and histopathological examinations were performed.nnnRESULTSnNo mortality, ophthalmic abnormalities or treatment-related clinical signs were identified during the study. As compared with the control group, significantly lower body weights and food consumption were observed in 1.5 and 4.5 g/kg bw groups. In clinical chemistry tests, triglyceride was significantly decreased and high-density lipoprotein cholesterol was significantly increased in all SIF-treated groups. Total testosterone levels were significantly lower in 0.50, 1.50, and 4.5 g/kg bw dose groups than in the control group. Microscopic examination showed that the mammary glands exhibited hyperplasia and excreted latex in rats of the 4.5 g/kg bw group. No changes attributable to treatment of SIF in other parameters were found.nnnCONCLUSIONnSIF at high dosages caused significant endocrine disruption in male rats. The no observed adverse effect level (NOAEL) of SIF to male rats in this study is considered to be 0.20 g/kg bw.

Subchronic toxicity study of GH transgenic carp.

A subchronic toxicity study of GH (growth hormone) transgenic carp was carried out with 60 SD rats aged 4 weeks, weight 115∼125 g. Ten male and 10 female rats were allotted into each group. Animals of the three groups (transgenic carp group (GH-TC), parental carp group (PC) and control group) were fed soy- and alfalfa-free diet (SAFD) with 10% GH transgenic carp powder, 10% parental carp powder or 10% common carp powder for 90 consecutive days, respectively. In the end of study, animals were killed by exsanguination via the carotid artery under diethyl ether anesthesia, then weights of heart, liver, kidneys, spleen, thymus, brain, ovaries and uterus/testis were measured. Pathological examination of organs was determined. Endocrine hormones of triiodothyronine (T3), thyroid hormone (T4), follicle-stimulating hormone (FSH), 17β-estradiol (E2), progesterone (P) and testosterone (T) levels were detected by specific ELISA kit. Parameters of blood routine and blood biochemical were measured. The weights of the body and organs of the rats, food intake, blood routine, blood biochemical test and serum hormones showed no significant differences among the GH transgenic carp-treated, parental carp-treated and control groups (P>0.05). Thus, it was concluded that at the dose level of this study, GH transgenic carp showed no subchronic toxicity and endocrine disruption to SD rats.

Products of oxidized L-Ascorbic Acid damage acellular DNA

ObjectiveL-ascorbic acid can be pro-oxidant and anti-oxidant in different reaction. This study aims to test the effects about products of oxidized L-Ascorbic Acid on acellular DNA.MeasurementAcellular DNA, nuclear DNA fixed on slides, are used in our experiment. There are four groups and one negative. Negative control is sham-treated with buffer(pH 7.2 and AA/H2O2/fenton free). Experimental groups are treated separately with 0.06 mM L-ascorbic acid (AA) alone(exposed in air), 0.06 mM L-ascorbic acid (AA) alone(no exposure in air), 1.2 mM hydrogen peroxide (H2O2) alone, and a mixture of final concentration of 0.03 mM L-ascorbic acid and 0. 6 mM hydrogen peroxide (AA+ H2O2). Each experimental group consists of 4 slides and each slide is treated for 4 hours at 4 °C in a dark place. The DNA damage is quantified by alkaline Comet Assay. The comet images are analysed by Comet Al.0 software. Differences among groups are compared with SPSS 11.0.ResultsDNA singlestrand breakage is found to be treatment-dependent in the following sequence: AA+ H2O2> AA(oxidized) > H2O2, AA(without oxidization) and Control.ConclusionAcellular DNA can tolerate the low concentration H2O2, but is sensitive to free radical. The results indicate that AA expose in air and mixture of AA and H2O2 can produce ·OH and L-dehydroascorbate (DHA), ·OH can damage DNA.

An Assessment of Androgenic/Anti­androgenic Effects of GH Transgenic Carp by Hershberger Assay*

OBJECTIVEnTo evaluate the androgenic and anti-androgenic effects of GH (growth hormone) transgenic carp in male rats.nnnMETHODSnHershberger assay was carried out in castrated male SD rats aged 4-5 weeks. Testosterone propionate (TP) (0.4 mg/kg BW) was administrated for a positive control, GH transgenic carp (3.0 g/kg BW)+TP (0.4 mg/kg BW), parental carp (3.0 g/kg BW) + TP (0.4 mg/kg BW), and flutamide (Flu) (3.0 g/kg BW) were used for negative controls, and vehicle was administered orally for a blank control. All groups were administrated for 10 consecutive days. At the end of the test, animals were anesthetized, then weights of accessory sex organ were measured. Serum testosterone (T), luteinizing hormone (LH), and Follicle-Stimulating Hormone (FSH) levels were detected.nnnRESULTSnThe weights ratios of the accessory sex organs and body weights showed no significant differences between the solvent control and the GH transgenic carp-treated groups. Serum concentrations of FSH, LH, and T of the rats treated with GH transgenic carp + TP showed no significant changes, compared with those treated with TP only.nnnCONCLUSIONnGH transgenic carp does not have any androgenic agonist or antagonist properties in vivo screening tests.

Evaluation of the in vitro and in vivo Genotoxicity of Almond Skins

OBJECTIVEnIt aims to study potential genotoxicity of almond skins.nnnMETHODSnA bacterial reverse mutation assay was performed on S. typhimurium strains TA97, TA98, TA100, TA102, and TA1535 in the absence or presence of S-9 mixture at a dose range of 312.5 to 5 000 μg/plate. A micronucleus test and a mammalian bone marrow chromosome aberration tests were performed in Swiss Albino (CD-1) mice at doses of 625, 1 250, and 2 500 mg/kg bw used.nnnRESULTSnAlmond skins exerted no mutagenic activity in various bacterial strains of Salmonella typhimurium in either the absence or the presence of metabolic activation at all doses tested. Various doses of almond skins did not affect the proportions of immature to total erythrocytes, the number of micronuclei in the immature erythrocytes, or the number of structural and numerical chromosomal aberrations of Swiss albino mice.nnnCONCLUSIONnAlmond skins are not genotoxic under the conditions of the in vitro bacterial reverse mutation assay and two in vivo tests - micronucleus test and mammalian bone marrow chromosome aberration test, which supports the safety of almond skins for dietary consumption.