Menaquinone-4 exerts a protective effect against carbon tetrachloride-induced acute liver injury in mice by alleviating ferroptosis / 临床肝胆病杂志

ObjectiveTo investigate whether menaquinone-4 （MK-4） can exert a protective effect against carbon tetrachloride （CCl4）-induced acute liver injury （ALI） in mice by alleviating ferroptosis. MethodsAfter adaptive feeding， adult male ICR mice， aged 8 weeks， were divided into Control group， MK-4 group， CCl4 model group （6-hour， 12-hour， and 24-hour）， and MK-4+CCl4 group （6-hour， 12-hour， and 24-hour）， with 6 mice in each group. The mice in the Control group were given intraperitoneal injection of an equal dose of corn oil； the mice in the MK-4 group were given intraperitoneal injection of 40 mg/kg MK-4 solution， followed by an equal dose of corn oil after 1 hour； the mice in the MK-4+CCl4 group （6-hour， 12-hour， and 24-hour） were given intraperitoneal injection of 40 mg/kg MK-4 solution， and after 1 hour， the mice in this group and the CCl4 model group （6-hour， 12-hour， and 24-hour） were given intraperitoneal injection of 0.3 mL/kg CCl4 solution， with samples collected at 6， 12， and 24 hours. HE staining was used to observe the pathological changes of mouse liver； Prussian blue staining was used to observe iron accumulation in liver tissue； a biochemical analyzer was used to measure the serum levels of aspartate aminotransferase （AST） and alanine aminotransferase （ALT）； related kits were used to measure the levels of tissue iron content and the oxidative stress indices malondialdehyde （MDA） and glutathione （GSH） in liver homogenate； RT-PCR was used to measure the expression levels of ferroptosis marker genes （acyl-CoA synthetase long-chain family member 4 ［ACSL4］， prostaglandin-endoperoxide synthase 2 ［PTGS2］， and glutathione peroxidase 4 ［GPX4］） and iron metabolism-related genes （hemojuvelin ［HJV］， transferrin receptor 1 ［TFR1］， and ferroportin ［FPN］）， and Western blot was used to measure the protein expression level of GPX4. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsIn the aging study， compared with the Control group， the CCl4 model group （6-hour， 12-hour， and 24-hour） had significant increases in liver weight coefficient and the serum levels of ALT and AST （all P<0.05）， and HE staining also showed that liver injury gradually aggravated over time. Meanwhile， compared with the CCl4 model group （6-hour， 12-hour， and 24-hour）， the MK-4+CCl4 （12-hour） group had significant reductions in liver weight coefficient and the serum levels of ALT and AST （all P<0.05）， with a reduction in the necrotic area of liver tissue， and therefore， 12-hour mouse tissue samples were used for detection in the following study. Compared with the Control group， the CCl4 group had a significant increase in MDA and a significant reduction in GSH （both P<0.05）， and compared with the CCl4 group， the MK-4+CCl4 group had a significant reduction in MDA and a significant increase in GSH （both P<0.05）. Compared with the Control group， the CCl4 group had significant increases in the key ferroptosis indices ASCL4 and PTGS2 and a significant reduction in GPX4 （all P<0.05）； compared with the CCl4 group， the MK-4+CCl4 group had significant reductions in the mRNA expression levels of ASCL4 and PTGS2 and a significant increase in the mRNA expression level of GPX4 （all P<0.05）. Western blotting showed that compared with the Control group， the CCl4 group had a significant reduction in the protein expression level of GPX4 （P<0.05）， and compared with the CCl4 group， the MK-4+CCl4 group had a significant increase in the protein expression level of GPX4 （P<0.05）. Prussian blue staining showed that compared with the Control group， the CCl4 group had a significant increase in iron accumulation； after MK-4 intervention， compared with the CCl4 group， the MK-4+CCl4 group had a significant reduction in iron accumulation. As for the measurement of iron metabolism genes in mouse liver， compared with the Control group， the CCl4 group had a significant increase in iron content， significant reductions in the mRNA expression levels of FPN and HJV， and a significant increase in the mRNA expression level of TFR1 （all P<0.05）； after protection with MK-4， there was a significant reduction in iron content， significant increases in the mRNA expression levels of FPN and HJV， and a significant reduction in the mRNA expression level of TFR1 （all P<0.05）. ConclusionMK-4 intervention in advance can alleviate CCl4-induced ALI in mice， possibly by inhibiting ferroptosis and improving the expression of iron metabolism-related genes in mouse liver.

Effect of Toll-like receptor 4 on liver regeneration during acetaminophen-induced liver injury in mice / 临床肝胆病杂志

Objective To investigate whether Toll-like receptor 4 (TLR4) inhibition affects liver regeneration during acetaminophen (APAP)-induced liver injury in mice, as well as the mechanism of TLR4 involved in liver regeneration. Methods A total of 78 male CD-1 mice were divided into nine groups using a random number table, i.e., three control groups (normal control group, solvent control group, inhibitor control group) with 6 mice in each group and six experimental groups (APAP 24-hour group, TAK-242+APAP 24-hour group, APAP 48-hour group, TAK-242+APAP 48-hour group, APAP 72-hour group, TAK-242+APAP 72-hour group) with 10 mice in each group. The mice in the experimental groups were given a single dose of intraperitoneally injected APAP (300 mg/kg), and TAK-242 was intraperitoneally injected at a dose of 3 mg/kg at 3 hours before APAP administration. Serum and liver tissue samples were collected at different time points. The biochemical method was used to measure the serum level of alanine aminotransferase (ALT); HE staining was used to observe liver pathological changes; RT-PCR, Western blot, and immunohistochemistry were used to measure the expression levels of Cyclin D1, PCNA, Ki-67, STAT3, and p-STAT3. The t -test was used for comparison of normally distributed continuous data between two groups; a one-way analysis of variance was used for comparison between multiple groups, and the least significant difference t -test was used for further comparison between two groups. The Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups, and the Kruskal-Wallis H test was used for comparison between multiple groups and further comparison between two groups. Results Compared with the normal control group, the APAP 24-hour and 48-hour groups had a significantly higher serum level of ALT (both P < 0.05), and the TAK-242+APAP 24-hour and 48-hour groups had a significantly higher serum level of ALT than the APAP group at the same time point (both P < 0.05). HE staining showed typical central lobular necrosis in the liver of APAP-treated mice, and the TAK-242+APAP 24-hour and 48-hour groups had a significantly larger necrotic area than the APAP group at the same time point (both P < 0.05). RT-PCR, Western blot, and immunohistochemistry showed that the TAK-242+APAP 24-hour, 48-hour, and 72-hour groups had significantly lower mRNA and protein expression levels of Cyclin D1 than the APAP group at the same time point (all P < 0.05); the TAK-242+APAP 24-hour, 48-hour, and 72-hour groups had a significantly lower mRNA expression level of PCNA than the APAP group at the same time point (all P < 0.05), and the TAK-242+APAP 24-hour and 48-hour groups had a significantly lower protein expression level of PCNA than the APAP group at the same time point (all P < 0.05); the TAK-242+APAP 24-hour and 72-hour groups had a significantly lower mRNA expression level of Ki-67 than the APAP group at the same time point (all P < 0.05), and the TAK-242+APAP 24-hour, 48-hour, and 72-hour groups had a significantly lower protein expression level of Ki-67 than the APAP group at the same time point (all P < 0.05). In addition, the TAK-242+APAP 24-hour and 48-hour groups had a significantly lower phosphorylation level of STAT3 than the APAP group at the same time point (both P < 0.05). Conclusion TLR4 may promote liver regeneration by increasing the phosphorylation level of STAT3 during APAP-induced liver injury in mice.

Qualitative and quantitative evaluation of Flos Puerariae by using chemical fingerprint in combination with chemometrics method / 药物分析学报

In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis(SA),hierarchical clustering analysis(HCA),principal components analysis(PCA),and orthogonal partial least squares discriminant analysis(OPLS-DA).Next,the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry(HPLC-FT-ICR MS).Then,the characteristic constituents in FP were quantitatively analyzed by HPLC.As a result,31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers.A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time,UV absorption wavelength,accurate mass,and MS/MS data with those of reference standards.Subsequently,the contents of glycitin,genistin,tectoridin,glycitein,genistein,and tectorigenin in 13 batches of FP were detected,ranging from 0.4438 to 11.06 mg/g,0.955 to 1.726 mg/g,9.81 to 57.22 mg/g,3.349 to 41.60 mg/g,0.3576 to 0.989 mg/g,and 2.126 to 9.99 mg/g,respectively.In conclusion,fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP.It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.

Immunomodulatory effect of human adipose derived mesenchymal stem cells on skin transplantation between different mouse strains / 中国组织工程研究

BACKGROUND: Skin transplantation is one of the most effective methods for treating large-area burns. How to effectively suppress the immune rejection after allogeneic skin transplantation is a problem that needs to be solved urgently. OBJECTIVE: To investigate the effect of human adipose derived mesenchymal stem cells (hADSCs) on the immunoregulation of skin grafts in different strains of mice. METHODS: Isolated hADSCs were cultured to the 3rd generation. Sixty ICR neonatal mice, 2-4 days of age, were randomly divided into four groups (n=15). The skin tissues of ICR neonatal mice were transplanted into adult C57BL/6 mice to establish a different strain of mouse skin graft immune rejection model. PBS and low dose (5×104), medium dose (10×104), high dose (20×104) hADSCs were injected into the model mice through tail vein, and the survival time of transplanted skin in each group was recorded. On the 7th day after operation, five mice from each group were randomly selected to remove their spleen and serum, and the expression of immune factors interleukin-10, tumor necrosis factor-α and interferon-γ were detected by RT-PCR and ELISA respectively. The transplanted part of the skin was taken to make pathological sections for observing the infiltration of lymphocytes. RESULTS AND CONCLUSION: Compared with the PBS group, the survival time of the skin was prolonged in the low dose hADSCs group; however, there was no significant difference between the two groups (P > 0.05). Compared with the PBS and low dose hADSCs groups, the survival time of the skin was significantly increased in the medium and high dose groups (P 0.05). Compared with the PBS group, the relative expression of tumor necrosis factor-α and interferon-γ in the spleen and serum was significantly decreased in the low, medium and high dose hADSCs groups (P < 0.05), whereas the level of interleukin-10 was significantly elevated in the medium and high dose hADSCs groups (P < 0.05). To conclude, the appropriate dose of hADSCs can significantly prolong the survival time of transplanted skin between different strains of mice, by regulating the expression of related immune factors in the recipient mice.

Metabonomic analysis of plasma biochemical changes in pyrexia rats after treatment with Gegenqinlian decoction, aspirin and itraconazole by UHPLC-FT-ICR-MS / 药物分析学报

A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR-MS) was used to investi-gate the changes in the endogenous metabolites in the plasma of rats with yeast-induced pyrexia treated with Gegenqinlian decoction (GQLD), aspirin and itraconazole. The differences in the small molecule profiles of treatment using traditional Chinese medicine, etiological treatment and symptomatic treat-ment were elucidated. Thirty-six plasma metabolites were identified or putatively identified, and the effects of the three medicines on the thirty-six metabolites were studied. Their metabolic pathways indicated that GQLD, aspirin and itraconazole ameliorated the rats with yeast-induced pyrexia pre-dominantly by regulating the metabolisms of phospholipid, sphingolipid, fatty acid oxidation, fatty acid amides, amino acid and glycerolipid in vivo. The pharmacodynamics and metabonomic results showed that the three medicines exhibited the therapeutic effects on pyrexia by regulating the perturbations of multiple metabolisms. The study provided a scientific basis for an in-depth understanding of the ther-apeutic effects of GQLD, aspirin and itraconazole on rats with yeast-induced pyrexia.

Abrupt Change in Electrophysiological Properties Begins From Postnatal Day 7 Before Hearing Onset in the Developing Mice Auditory Cortical Layer II/III Neurons

OBJECTIVES: In the developing auditory cortex, maturation of electrophysiological properties and cell types before and after hearing onset has been reported previously. However, the exact timing of firing pattern change has not been reported. In this study, firing pattern change was investigated from postnatal day 3 (P3) to P12 in auditory cortical layer II/III neurons to investigate whether firing pattern changes dramatically after a specific point during development. METHODS: ICR mice pups aged from P3 to P12 were sacrificed to obtain 300-mm-thick brain slices containing the primary auditory cortex. From cortical layer II/III neurons, the patterns of action potential firing generated by current injection were examined using whole cell current clamp technique and the characteristics of Na⁺ currents involved in action potential firing were investigated using whole cell voltage clamp technique. RESULTS: From P3 to P6, most cells did not show action potential firing (29 of 46 cells), and some cells responding to current injection showed a single action potential at the initial depolarizing current step (17 of 46 cells). This firing pattern changes from P7. From P7 to P9, cells begin to show regular spiking to current injection. The spiking frequency increased after P10. In studying Na⁺ current with whole cell voltage clamp, Na⁺ current densities increased gradually (32.0±2.0 pA/pF [P3–P6, n=7], 51.2±2.0 pA/pF [P7–P9, n=13], and 69.5±3.7 pA/pF [P10–P12, n=13]) in low external [Na⁺] condition. Na⁺ current recovery was accelerated and inactivation curves shifted to hyperpolarization with age. CONCLUSION: As regular spiking cells were observed from P7 but never from P3 to P6, P7 might be regarded as an important milestone in the development of auditory cortical layer II/III neurons. This change might mainly result from the increase in Na⁺ current density.

Comparison of toxic responses to acetaminophen challenge in ICR mice originating from different sources / 한국실험동물학회지

Acetaminophen (APAP) is the most common antipyretic analgesic worldwide. However, APAP overdose causes severe liver injury, especially centrilobular necrosis, in humans and experimental animals. At therapeutic dosage, APAP is mainly metabolized by sulfation and glucuronidation, and partly by cytochrome P450–mediated oxidation. However, APAP overdose results in production of excess reactive metabolite, N-acetyl-p-benzoquinone imine (NAPQI), by cytochromes P450; NAPQI overwhelms the level of glutathione (GSH), which could otherwise detoxify it. NAPQI binds covalently to proteins, leading to cell death. A number of studies aimed at the prevention and treatment of APAP-induced toxicity are underway. Rats are more resistant than mice to APAP hepatotoxicity, and thus mouse models are mainly used. In the present study, we compared the toxic responses induced by APAP overdose in the liver of ICR mice obtained from three different sources and evaluated the usability of the Korl:ICR stock established by the National Institute of Food and Drug Safety Evaluation in Korea. Administration of APAP (300 mg/kg) by intraperitoneal injection into male ICR mice enhanced CYP2E1 protein expression and depleted hepatic GSH level 2 h after treatment accompanied with significantly increased level of hepatic malondialdehyde, a product of lipid peroxidation. Regardless of the source of the mice, hepatotoxicity, as evidenced by activity of serum alanine aminotransferase, increased from 8 h and peaked at 24 h after APAP treatment. In summary, hepatotoxicity was induced after the onset of oxidative stress by overdose of APAP, and the response was the same over time among mice of different origins.

Effect of fibroblast growth factor 21 on hepatic fibrosis in mice and its mechanism / 临床肝胆病杂志

To investigate the effect of fibroblast growth factor 21 (FGF21) on hepatic fibrosis in mice and the mechanism of its action.Methods Male ICR mice were randomly divided three groups : control group, model group (treated with CCl4 ), and treatment group (treated with CCl4 +1.0 mg/kg FGF21).All mice were sacrificed to collect serum and liver tissues after 36 consecutive days of treatment.Serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBil), interleukin -6 (IL -6), interleukin -1β(IL -1β), and tumor necrosis factor -α(TNF -α) were measured.Liver pathological changes were analyzed by Masson staining .The hepatic 4 -hydroxyproline (4 -Hyp) level was measured using a hydroxyproline detection kit.The mRNA levels of hepatic collagen I, α-smooth muscle actin (α-SMA), transforming growth factor -β(TGF -β), IL -6, IL - 1β, and TNF -αwere determined by quantitative real -time PCR.Comparison between multiple groups was made by one -way analysis of variance, and comparison between any two groups weas made using the LSD -t test.Results The Masson staining showed that the model group had a significantly higher degree of hepatic fibrosis than the control group , and the treatment group had a significantly lower degree of hepatic fibrosis than the model group.The model group had significantly higher serum levels of ALT , AST, ALP, and TBil (all P <0.05),and the treatment group showed significant reductions in the above parameters compared with the model group (all P <0.05).Enzyme - linked immunosorbent assay indicated that the model group had significantly higher serum levels of IL -1β, IL -6, and TNF -αthan the control group (all P <0.05), and the treatment group showed significant reductions in the above parameters compared with the model group (all P <0.05).The hepatic 4 -Hyp level and mRNA levels of collagen I and α-SMA were significantly higher in the model group than in the control group (P =0.04, <0.001, and <0.001), and they were significantly lower in the treatment group than in the model group (P =0.005, <0.001, and <0.001).The hepatic mRNA levels of TGF -β, IL -6, IL -1β, and TNF -αwere significantly higher in the model group than in the control group(all P <0.001), and they were significantly lower in the treatment group than in the control group (all P <0.001).Conclusion FGF21 attenuates hepatic fibrogenesis in mice, possibly by inhibiting the expression of TGF -β, IL -6, IL - 1β, and TNF -αin the liver.

Comparison of the anesthetic effects of 2,2,2-tribromoethanol on ICR mice derived from three different sources / 한국실험동물학회지

This study was conducted to compare the anesthetic effects of 2,2,2-tribromoethanol (TBE, Avertin®) in ICR mice obtained from three different sources. TBE (2.5%) was intraperitoneally injected at three doses: high-dose group (500 mg/kg), intermediate-dose group (250 mg/kg), and low-dose group (125 mg/kg). Anesthesia time, recovery time, end-tidal peak CO2 (ETCO₂), mean arterial blood pressure, heart rate, oxygen saturation (SpO₂), body temperature, pH, PCO₂, and PO₂ of the arterial blood were measured. Stable anesthesia was induced by all doses of TBE and the anesthesia time was maintained exhibited dose dependency. No significant differences in anesthetic duration were found among the three different strains. However, the anesthesia time was longer in female than in male mice, and the duration of anesthesia was significantly longer in female than in male mice in the high-dose group. The recovery time was significantly longer for female than male mice in the intermediate- and high-dose groups. In the ICR strains tested, there were no significant differences in the mean arterial blood pressure, SPO₂, arterial blood PCO₂, and PO₂, which decreased after TBE anesthesia, or in heart rate and ETCO₂, which increased after TBE anesthesia. In addition, body temperature, blood biochemical markers, and histopathological changes of the liver, kidney, and lung were not significantly changed by TBE anesthesia. These results suggested that ICR mice from different sources exhibited similar overall responses to a single exposure to TBE anesthesia. In conclusion, TBE is a useful drug that can induce similar anesthetic effects in three different strains of ICR mice.

Comparison of scopolamine-induced cognitive impairment responses in three different ICR stocks / 한국실험동물학회지

Cognitive impairment responses are important research topics in the study of degenerative brain diseases as well as in understanding of human mental activities. To compare response to scopolamine (SPL)-induced cognitive impairment, we measured altered parameters for learning and memory ability, inflammatory response, oxidative stress, cholinergic dysfunction and neuronal cell damages, in Korl:ICR stock and two commercial breeder stocks (A:ICR and B:ICR) after relevant SPL exposure. In the water maze test, Korl:ICR showed no significant difference in SPL-induced learning and memory impairment compared to the two different ICRs, although escape latency was increased after SPL exposure. Although behavioral assessment using the manual avoidance test revealed reduced latency in all ICR mice after SPL treatment as compared to Vehicle, no differences were observed between the three ICR stocks. To determine cholinergic dysfunction induction by SPL exposure, activity of acetylcholinesterase (AChE) assessed in the three ICR stocks revealed no difference of acetylcholinesterase activity. Furthermore, low levels of superoxide dismutase (SOD) activity and high levels of inflammatory cytokines in SPL-treated group were maintained in all three ICR stocks, although some variations were observed between the SPLtreated groups. Neuronal cell damages induced by SPL showed similar response in all three ICR stocks, as assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, Nissl staining analysis and expression analyses of apoptosis-related proteins. Thus, the results of this study provide strong evidence that Korl:ICR is similar to the other two ICR. Stocks in response to learning and memory capacity.

Staphylococcus sciuri associated to subcutaneous abscess and dermatitis in ICR mouse / Staphylococcus sciuri associado a abcesso subcutâneo e dermatite em ratos

Subcutaneous mass was found in ICR mouse during daily health observation in the breeding colony of the National Laboratory Animal Center, Mahidol University, Thailand. The animal was subsequently culled and humanely sacrificed due to the institutional preventive medicine policy. Microbiological and histopathological studies were performed for definitive diagnosis. The results described that the case was subcutaneous abscess and chronic dermatitis in association with Staphylococcus sciuri infection without epizootic and mortality. This was determined as the first reported case in Thailand occurring in mouse. Reproductive stress and abrasion skin wound may be the predisposing factors. Although pathogenic staphylococci in laboratory animals are limited to S. aureus and S. xylosus, S. sciuri opportunistic properties, natural history, and heterogeneity should not be forgotten.(AU)

Uma massa subcutânea foi encontrada em um rato ICR durante uma observação diária de saúde na colônia reprodutora do Laboratório do Centro Animal Nacional, na Universidade de Mahidol, Tailândia. O animal foi selecionado e humanamente sacrificado devido à política institucional de medicina preventiva. Estudos microbiológicos e histopatológicos foram realizados para um diagnóstico definitivo. Os resultados descrevem que o caso foi um abcesso subcutâneo e dermatite crônica associado com infecção por Staphylococcus sciuri sem epizootia e mortalidade. Este foi determinado como o primeiro caso relatado em ratos na Tailândia. Estresse reprodutivo e ferida abrasiva na pele podem ser os fatores de predisposição. Apesar de staphylococci patogênicos em animais de laboratório serem limitados a S. aureus E S. xylosus, as propriedades oportunistas, história natural e heterogeneidade do S. sciuri não devem ser esquecidos.(AU)

Comparison of therapeutic responses to an anticancer drug in three stocks of ICR mice derived from three different sources / 한국실험동물학회지

Korl:ICR mice, established by the Korean National Institute of Food and Drug Safety Evaluation (NIFDS), are characterized based on their genetic variation, response to gastric injury, and response to constipation inducers. To compare the inhibitory responses of ICR stocks obtained from three different sources to the anticancer drug cisplatin (Cis), alterations in tumor volume, histopathological structure, and toxicity were examined in Sarcoma 180 tumor-bearing Korl:ICR, A:ICR (USA source), and B:ICR (Japan source) mice treated with low and high concentrations of Cis (L-Cis and H-Cis, respectively). Tumor size and volume were lower in H-Cis-treated mice than in L-Cis-treated mice in all three ICR stocks with no significant differences among stocks. There was a significant enhancement of the necrotizing areas in the histological structures in the L-Cis- and H-Cis-treated groups relative to that in the untreated group. The necrotizing area changes were similar in the Sarcoma 180 tumor-bearing Korl:ICR, A:ICR, and B:ICR mice. However, there were stock-bases differences in the serum biomarkers for liver and kidney toxic effects. In particular, the levels of AST, ALT and BUN increased differently in the three H-Cis-treated ICR stocks, whereas the levels of ALP and CRE were constant. Taken together, the results of the present study indicate that Korl:ICR, A:ICR, and B:ICR mice have similar overall inhibitory responses following Cis treatment of Sarcoma 180-derived solid tumors, although there were some differences in the magnitude of the toxic effects in the three ICR stocks.

Comparative analysis of basal locomotor activity-related metabolic phenotypes between C57BL/6 mice and ICR mice substrains derived from three different sources / 한국실험동물학회지

Animal model, as an indispensable tool for scientific purposes of biomedical researches and clinical application, is a commonly used in various researches. Regarding to this, it is necessary to establish the metabolic phenotype of animal model to minimize spurious interpretations and ensure a level of accuracy and reliability adequate for experimental research. However, the metabolic phenotype-related analysis within rodent strains derived from different source is nonexistent, especially in C57BL/6Korl mice and Korl:ICR mice (a domestic mouse strain). To compare the physiological and metabolic phenotypes over a period of time, we utilized the C57BL/6 mice (C57BL/6Korl, A:C57BL/6, and B:C57BL/6) and ICR mice (Korl:ICR, A:ICR, and B:ICR) derived from three different sources. Our data showed that average body weight, body temperature, food intake, and water consumption have a similar tendency among the C57BL/6 and ICR groups, except for the higher body weight of C57BL/6Korl mice over a period of time. Moreover, some significant differences was observed in adipose tissue mass and adipocyte size among the groups, with a higher tendency of C57BL/6Korl mice and Korl:ICR mice. Most importantly, resting metabolic rate (RMR) serves as an approximation of the metabolic phenotype showed no significant difference among the groups of C57BL/6 mice and ICR mice, except for the lower oxygen uptake of C57BL/6Korl mice compare to the A:C57BL/6 mice. Taken together, our data suggest that C57BL/6 mice and ICR mice derived from three different sources have an overall similar feature of physiological and metabolic phenotypes.

Comparison of the response using ICR mice derived from three different sources to multiple low-dose streptozotocin-induced diabetes mellitus / 한국실험동물학회지

This study was conducted to compare the multiple low-dose streptozotocin (MLDS)-induced diabetic patterns of Korl:ICR, A:ICR, and B:ICR mice obtained from three different sources. Six-week-old male ICR mice were obtained from three difference sources. Korl:ICR mice were kindly provided by the National Institute of Food and Drug Safety Evaluation (NIFDS). The other two groups of ICR mice were purchased from different vendors located in the United States (A:ICR) and Japan (B:ICR). All ICR mice that received MLDS exhibited overt diabetic symptoms throughout the study, and the incidence and development of diabetes mellitus were similar among the three ICR groups. The diabetic mice exhibited hyperglycemia, loss of body weight gain, decreased plasma insulin levels, impaired glucose tolerance, decreased number of insulin-positive cells, and decreased size of β-cells in the pancreas. The diabetes symptoms increased as the blood glucose level increased in the three ICR groups. In particular, the level of blood glucose in the STZ-treated group was higher in Korl:ICR and A:ICR mice than in B:ICR mice. The plasma insulin levels, glucose tolerance, blood chemistry, and morphological appearance of the pancreas were very similar in the ICR groups obtained from the three different sources. In conclusion, our results suggest that Korl:ICR, A:ICR, and B:ICR mice from different sources had similar overall responses to multiple low-dose STZ to induce diabetes mellitus.

Comparision of doxorubicin-induced cardiotoxicity in the ICR mice of different sources / 한국실험동물학회지

Doxorubicin is a widely used chemotherapeutic agents and is now part of standard therapeutic regimens for a variety of cancers (eg, hematopoietic malignancies and advanced solid tumors of the breast, ovary, thyroid, and bone). However, a potentially lethal and dose-dependent cardiotoxicity that appears within a short time after treatment limits the usage of doxorubicin in cancer patients. Although the mechanism of doxorubicin-induced cardiotoxicity is not completely understood, it is thought that free radical-induced oxidative stress and excessive production of reactive oxygen species are primary drivers of its toxicity. In this study, we compared the doxorubicin-induced cardiotoxicity of ICR mice obtained from three different sources and evaluated the utility of Korl:ICR stock established by the Korean FDA. Because doxorubicin-induced cardiotoxicity is thought to involve the excessive generation of ROS followed by oxidative stress, we determined the representative tissue index of oxidation, lipid peroxidation, and antioxidant, glutathione (GSH), as well as the parameters of heart injury. Doxorubicin treatment successfully induced cardiotoxicity as evidenced by histological examination and serum parameters (eg, levels of LDH and CK activities) in ICR mice. It was accompanied by increased lipid peroxidation and a decrease in both cysteine and GSH, further supporting previous reports that oxidative stress is a potential mechanism of doxorubicin-induced cardiotoxicity. Of interest, we did not observe a significant difference in doxorubicin-induced cardiotoxicity among mice of different origins. Collectively, our results suggest that Korl:ICR strain may be useful in the research of doxorubicin-induced cardiotoxicity.

Annual tendency of research papers used ICR mice as experimental animals in biomedical research fields / 한국실험동물학회지

Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields.

Comparison of commonly used ICR stocks and the characterization of Korl:ICR / 한국실험동물학회지

Mouse is a commonly used animal in life science studies and is classified as outbred if genetically diverse and inbred if genetically homogeneous. Outbred mouse stocks, are used in toxicology, oncology, infection and pharmacology research. The National Institute of Food and Drug Safety Evaluation (NIFDS; former the Korea National Institute of Health) have bred ICR mice for more than 50 years. We investigated to provide users with information and promote accountability to the Korl:ICR. To secure the indigenous data, biological characteristics of Korl:ICR were identified by comparing with other ICR stocks. This domestic ICR stock was denominated as ‘Korl:ICR’. Phylogenetic analysis using SNPs indicated that the population stratification of the Korl:ICR was allocated different area with other ICR. In addition, we measured litter size, body weight, body length, various organ weight, hematology and clinical blood chemistry of the Korl:ICR compared to other ICR. Otherwise, there are no significant differences among the biological phenotypes of Korl:ICR and other ICR. These results suggest that as a genetically indigenous source colony, the Korl:ICR is seperated (or independent) stock with other ICR. Also, we confirmed that there is no difference among the Korl:ICR and other ICR on biological phenotypes. Therefore, the Korl:ICR source colony might be a new stock in distinction from other ICR, it is a good milestone in securing ownership of the national laboratory animal resource. The NIFDS expects that the Korl:ICR mice will be useful animal resource for our domestic researchers.

Acute and 13-week subchronic toxicological evaluations of turanose in mice

BACKGROUND/OBJECTIVES: Turanose, α-D-glucosyl-(1→3)-α-D-fructose, is a sucrose isomer which naturally exists in honey. To evaluate toxicity of turanose, acute and subchronic oral toxicity studies were conducted with ICR mice. MATERIALS AND METHODS: For the acute oral toxicity study, turanose was administered as a single oral dose [10 g/kg body weight (b.w.)]. In the subchronic toxicity study, ICR mice were administered 0, 1.75, 3.5, and 7 g/kg b.w. doses of turanose daily for 13 weeks. RESULTS: No signs of acute toxicity, including abnormal behavior, adverse effect, or mortality, were observed over the 14-day study period. In addition, no changes in body weight or food consumption were observed and the median lethal dose (LD₅₀) for oral intake of turanose was determined to be greater than 10 g/kg b.w. General clinical behavior, changes in body weight and food consumption, absolute and relative organ weights, and mortality were not affected in any of the treatment group for 13 weeks. These doses also did not affect the macroscopic pathology, histology, hematology, and blood biochemical analysis of the mice examined. CONCLUSION: No toxicity was observed in the acute and 13-week subchronic oral toxicology studies that were conducted with ICR mice. Furthermore, the no-observed-adverse-effect level is greater than 7 g/kg/day for both male and female ICR mice.

Anti-fatigue effect of compound schisandra extracts in mice and its mechanism / 吉林大学学报(医学版)

Objective:To study the effects of compound schisandra extracts (CSE) (schisandra,astragalus,acanthopanax,and rhodiola)on the exhaustive swimming time and the levels of blood urea nitrogen(BUN),serum lactic acid(LD),liver glycogen and muscle glycogene,superoxide dismutase(SOD)activity,and malonaldehyde(MDA) level in the mice and to charify its anti-fatigue effect and the mechanism.Methods:Eighty male ICR mice were randomly divided into blank control group,50 mg·kg-1 CSE group,100 mg·kg-1 CSE group,and 200 mg·kg-1CSE group;there were 20 mice in each group.The mice were administered orally for 30 d.Then 10 mice were randomly selected for exhaustive swimming test in each group and the exhaustive swimming time of the mice was recorded.The remaining 10 mice in each group were used for 90 min swimming,then all the mice were sacrificed and the blood and tissue samples were taken for the measurement of the levels of BUN,LD,liver glycogen and muscle glycogen,the SOD activity and MDA level;the total inhibitory rate of oxidation of CSE in vitro was determined by linoleic acid-ferric thiocyanate method.Results:Compared with blank control group,the exhaustive swimming time of the mice in 50,100,and 200 mg·kg-1 CSE groups were significantly increased (P<0.01);the levels of BUN and LD of the mice in 100 and 200 mg·kg-1 CSE groups were significantly decreased (P<0.05 or P<0.01);the levels of liver glycogen and muscle glycogen of the mice in 100 and 200 mg·kg-1 groups were significantly increased(P<0.05 or P<0.01);whereas the SOD activities were significantly increased and the levels of MDA were decreased(P<0.05 or P<0.01).Compared with 100 mg·kg-1 CSE group,the levels of serum BUN and LD of the mice in 200 mg·kg-1 CSE group were decreased (P<0.01),and the levels of liver glycogen and muscle glycogen were increased(P<0.05).The total inhibitory rate of oxidation of 5 g·L-1CSE was 76.94%.Conclusion:CSE has an anti-fatigue effect and the mechanism may be related to anti-oxidation effect.

Establishment of first mandibular molar development of the time sequence in ICR mice / 中国比较医学杂志

Objective This study aims to understand the characteristics of the time sequence of ICR mouse first mandibular molar tooth germ development through dynamic observation.Methods Tooth germ of Embryos (E11.5,E12.5,E13.5,E14.5,E15.5,E16.5,E17.5 and E18.5) and postnatal (PN1,PN2) mice were obtained.The heads (E11.5-E15.5) and mandibles (E16.5-PN2) of mice were dissected,fixed and embedded for serial sections and HE staining.All the results were assessed under light microscopy.Results The tooth germ underwent various development stages including the bud,cap and bell stages.Mouse odontogenesis was initiated at E11.5.Proliferation of oral epithelium formed the bud stage at E13.5.Then the cap stage was observed at E14.5-E15.5 and the bell stage was appeared beginning from E16.5.The pre-dentin was observed at PN1,as well as the dentin at PN2.Conclusions Establishing the regular development pattern of the first mandibular molar of ICR mice will provide a reliable basis for the future use in the specific tooth germ developmental research.