BACKGROUND: Although reperfusion is a salvaging method for an acute myocardial infarction, the act of reperfusion itself can paradoxically result in reactive oxygen species (ROS) mediated myocyte death. Propofol has been reported to remove ROS. This study tested the hypothesis that propofol protects H9c2 cardiomyoblasts against hypoxia/reoxygenation (H/R) injury. METHODS: For the H/R group of cells, hypoxia was induced by replacing the culture medium with serum-/-glucose free Dulbecco's modified Eagle's medium (DMEM) and by exposing cells to 0.5% O2 for 24 h. Following hypoxia, the cells were reoxygenated. The medium was then replaced with fresh medium for maintenance and propofol (0, 25, 50, 250micrometer) was added to the cells (n = 3 for each concentration). In the normoxia group of cells (n = 3), cells were incubated under 21% O2 for 48 h without propofol. The MTT (3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay was performed 8 and 24 h after reoxygenation for the H/R group of cells, and 32 and 48 h for the normoxia group of cells. The results of the MTT assay were determined with an ELISA spectrometer at a wavelength of 595 nm. RESULTS: At 8 and 24 h after reoxygenation, MTT formazans in the H/R group of cells were significantly reduced as compared with the normoxia group of cells (P < 0.05). In the presence of 25, 50 and 250micrometer propofol, the MTT activity at 8 and 24 h after reoxygenation was diminished when compared to exposure to 0micrometer propofol (P < 0.05). However, the formazans produced when cells were exposed to a concentration of 25micrometer in propofol convalesced to the level of 0micrometer propofol at 24 h after reoxygenation. CONCLUSIONS: These results suggest that propofol may play a role in increasing the number of non-viable cells during reoxygenation of the heart.
Animals ; Anoxia ; Cell Survival* ; Enzyme-Linked Immunosorbent Assay ; Formazans ; Heart* ; Muscle Cells ; Myocardial Infarction ; Propofol* ; Rats* ; Reactive Oxygen Species ; Reperfusion ; Reperfusion Injury

The methanol extract from the leaves of Petasites japonicus Maxim (PJ) was studied for its (anti-)mutagenic effect with the SOS chromotest and reverse mutation assay. The (anti-)carcinogenic effects were evaluated by the cytotoxicity on human cancer line cells and by the function and the expression of gap junctions in rat liver epithelial cell. PJ extracts significantly decreased spontaneous beta-galactosidase activity and beta-galactosidase activity induced by a mutagen, ICR, in Salmonella (S.) typhimurium TA 1535/pSK 1002. All doses of the extract (0.08-100 mg/plate) decreased the reversion frequency induced by benzo (alpha)pyrene (BaP) in S. typhimurium TA 98. It decreased not only the spontaneous reversion frequency but also that induced by BaP in S. typhimurium TA 100. PJ extract showed greater cytotoxic effects on human stomach, colon and uterus cancer cells than on other cancer cell types and normal rat liver epithelial cells. Dye transfers though gap junctions were significantly increased by PJ extracts at concentrations greater than 200 microg/mL and the inhibition of dye transfer by 12-O-tetradecanoylphorobol-13-acetate (TPA) was obstructed in all concentrations of PJ. PJ significantly increased the numbers of gap junction protein connexin 43, and increased the protein expression decreased by TPA in a dose-dependent manner. Based on these findings, PJ is suggested to contain antimutagenic and anticarcionogenic compounds.
Animals ; Cell Line, Tumor ; Cell Survival/*drug effects ; Formazans/chemistry ; Gap Junctions/*metabolism ; Humans ; Mutagenicity Tests ; Petasites/*metabolism ; Plant Extracts/*pharmacology ; Plant Leaves/metabolism ; Rats ; Tetrazolium Salts/chemistry

PURPOSE: Avulsed tooth can be completely recovered, if sound periodontal ligament (PDL) of tooth is maintained. Although a lot of storage solutions have been explored for the better storage of avulsed tooth, there is a shortcoming that the preservation time is much short. On the other hand, there has been studies that (-)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, which is related to the anti inflammatory, antioxygenic, and antibacterial effects, allows the successful preservations of tissues and cells. This study evaluated the effect of EGCG on avulsed-teeth preservation of Beagle dogs for a period of time. METHODS: The atraumatically extracted teeth of Beagle dogs were washed and preserved with 0/10/100 microM of EGCG at the time of immediate, period 1 (4 days in EGCG-contained media and additional 1 day in EGCG-free media), period 2 (8 days in EGCG-contained media and additional 2 days in EGCG-free media) and period 3 (12 days in EGCG-contained media and additional 2 days in EGCG-free media). Then, the cell viabilities of preserved teeth was calculated by dividing optical density (OD) of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with OD of eosin assay to eliminate the measurement errors caused by the different tissue volumes. RESULTS: From the results, the immediately analyzed group presented the highest cell viability, and the rate of living cells on teeth surface decreased dependent on the preservation period. However, the 100 microM of EGCG-treated group showed statistically significant positive cell activity than EGCG-free groups throughout preservation periods. CONCLUSIONS: Our findings showed that 100 microM EGCG could maintain PDL cell viability of extracted tooth. These results suggest that although EGCG could not be a perfect additive for tooth preservation, it is able to postpone the period of tooth storage. However, further in-depth studies are required for more plausible use of EGCG.
Animals ; Catechin ; Cell Survival ; Dogs ; Eosine Yellowish-(YS) ; Formazans ; Hand ; Organ Preservation ; Periodontal Ligament ; Tea ; Tetrazolium Salts ; Thiazoles ; Tooth ; Tooth Avulsion ; Tooth Replantation

PURPOSE: Avulsed tooth can be completely recovered, if sound periodontal ligament (PDL) of tooth is maintained. Although a lot of storage solutions have been explored for the better storage of avulsed tooth, there is a shortcoming that the preservation time is much short. On the other hand, there has been studies that (-)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, which is related to the anti inflammatory, antioxygenic, and antibacterial effects, allows the successful preservations of tissues and cells. This study evaluated the effect of EGCG on avulsed-teeth preservation of Beagle dogs for a period of time. METHODS: The atraumatically extracted teeth of Beagle dogs were washed and preserved with 0/10/100 microM of EGCG at the time of immediate, period 1 (4 days in EGCG-contained media and additional 1 day in EGCG-free media), period 2 (8 days in EGCG-contained media and additional 2 days in EGCG-free media) and period 3 (12 days in EGCG-contained media and additional 2 days in EGCG-free media). Then, the cell viabilities of preserved teeth was calculated by dividing optical density (OD) of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with OD of eosin assay to eliminate the measurement errors caused by the different tissue volumes. RESULTS: From the results, the immediately analyzed group presented the highest cell viability, and the rate of living cells on teeth surface decreased dependent on the preservation period. However, the 100 microM of EGCG-treated group showed statistically significant positive cell activity than EGCG-free groups throughout preservation periods. CONCLUSIONS: Our findings showed that 100 microM EGCG could maintain PDL cell viability of extracted tooth. These results suggest that although EGCG could not be a perfect additive for tooth preservation, it is able to postpone the period of tooth storage. However, further in-depth studies are required for more plausible use of EGCG.
Animals ; Catechin ; Cell Survival ; Dogs ; Eosine Yellowish-(YS) ; Formazans ; Hand ; Organ Preservation ; Periodontal Ligament ; Tea ; Tetrazolium Salts ; Thiazoles ; Tooth ; Tooth Avulsion ; Tooth Replantation

OBJECTIVETo introduce a rapid colorimetric method for assessing the viability of osteosarcoma cells after chemotherapy.

METHODSColorimetric assay and automatic microplate scanning spectrophotometer were used for assaying the viability of osteosarcoma cells.

RESULTSClose correlation was found between the absorbance at 570 nm of the formazan products and the number of viable osteosarcoma cells.

CONCLUSIONAn effective, sensitive and convenient colorimetric assay has been established to assess the survival of osteosarcoma cells following chemotherapy.

Antineoplastic Agents ; therapeutic use ; Bone Neoplasms ; drug therapy ; pathology ; Cell Survival ; drug effects ; Colorimetry ; methods ; Formazans ; Humans ; Osteosarcoma ; drug therapy ; pathology ; Sensitivity and Specificity ; Tetrazolium Salts

In order to establish a new more rapid, safe and sensitive colorimetric assay for the proliferation of leukemic cells, MTS/pms has been developed. This automated colorimetric assay is based on the characteristic of viable and metabolically active leukemic cells to cleave MTS/pms into a water-soluble product whose optical density is determined at 492 nm by an automated microtiter-plate reader photometer. The results indicated that only active leukemic cells cleaved MTS/pms into product measured, and dead cells did not reduce MTS/pms. A linear relations hip were found between the viable cell number and optical density of MTS/pms cleaved by HL-60 and K562 cell (r = 0.963). Compared with MTT and INT assays, the reduced product of MTS/pms is water-soluble. It is concluded that MTS/pms colorimetric assay is more rapid, accurate and sensitive for the bioassay of proliferation of leukemic cells.
Cell Division ; Colorimetry ; methods ; Formazans ; metabolism ; HL-60 Cells ; Humans ; K562 Cells ; Leukemia ; pathology ; Methylphenazonium Methosulfate ; metabolism ; Tetrazolium Salts ; metabolism ; Thiazoles ; metabolism

OBJECTIVETo determine the effects of organic amine diphenhydramine on the 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide dye (MTT) reduction assay.

METHODSThe primarily cultured cortical astrocytes were incubated with various concentrations of diphenhydramine for 24 h. To analyze the effects of diphenhydramine and other organic amines on the MTT assay, the data obtained from the MTT assay were compared with the results obtained from morphological observation and hoechst 33342 and propidium iodide (PI) nucleus double staining.

RESULTThe MTT assay showed that diphenhydramine (10(-4)mol/L), pyrilamine (10 (-4)mol/L) and zolantidine (10 (-5)mol/L) caused a significant increase in MTT reduction in astrocytes. However there was no proliferation, apoptosis or necrosis detected by hoechst and PI nucleus double staining. Light microscopy revealed that exocytosis of formazan granules was inhibited by diphenhydramine.

CONCLUSIONDiphenhydramine and other organic amines may enhance MTT reduction by suppression of MTT formazan exocytosis in astrocytes, which may affect the results of cell viability studies.

Animals ; Astrocytes ; drug effects ; metabolism ; physiology ; Cell Survival ; Cells, Cultured ; Diphenhydramine ; pharmacology ; Drug Interactions ; Formazans ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley ; Tetrazolium Salts ; pharmacokinetics

OBJECTIVETo determine the effect of aspirin on cell proliferation, alkaline phosphatase (ALP) activity, cell cycle and apoptosis in murine bone marrow stromal cells, so as to explore an appropriate dose range to improve bone regeneration in periodontal treatment.

METHODSST2 cells were stimulated with aspirin (concentrations of 1, 10, 100 and 1 000 μmol/L) for 1, 2, 3, 5 and 7 d. Cell proliferation was measured by methyl thiazolyl tetrazolium (MTT) assay. After ST2 cells were treated for 1, 3 and 7 d, ALP activity was measured by ALP kit, cell cycle and apoptosis were measured by flow cytometry (FCM) after treated for 48 h.

RESULTSMTT assays showed that various doses of aspirin have different effects on the cell growth. Briefly, lower concentrations (1, 10 μmol/L) of aspirin promoted the cell growth, the A value of 0, 1 and 10 μmol/L aspirin 7-day-treated cells were 0.313±0.012, 0.413±0.010 and 0.387±0.017 respectively (P <0.01 vs control), and so did the ALP level ([4.3±0.9], [6.0±0.3] and [7.7±0.4] μmol·min(-1)·g(-1), P <0.05 vs control), while higher concentrations, especially 1000 μmol/L of aspirin might inhibit the cell growth with time going, A value and ALP level were 0.267±0.016, (4.3±1.3) μmol·min(-1)·g(-1) respectively (P <0.05 vs control). Cell cycle analysis revealed no changes in comparison to control cells after treatment with 1 or 10 μmol/L aspirin, but it was observed that cell mitosis from S phase to G2/M phase proceeded at higher concentrations of 100 μmol/L aspirin, and the cell cycle in phase G0/G1 arrested at 1000 μmol/L. Parallel apoptosis/necrosis studies showed that the percentage of cells in apoptosis decreased dramatically at all doses of aspirin, the apoptosis rates of ST2 cells responded to 0, 1, 10, 100 and 1000 μmol/L aspirin were (11.50±0.90)%, (5.30±0.10)%, (5.50±0.10)%, (4.90±0.90)% and (7.95±0.25)% respectively (P<0.05 vs control).

CONCLUSIONSThis study demonstrated that lower dosage of aspirin can promote ST2 cells growth, osteogenic activity and inhibit its apoptosis. Aspirin maybe used for the bone reconstruction with a proper concentration.

Alkaline Phosphatase ; metabolism ; Animals ; Apoptosis ; drug effects ; Aspirin ; administration & dosage ; pharmacology ; Bone Regeneration ; Cell Cycle ; drug effects ; Cell Division ; Cell Line, Tumor ; Cell Proliferation ; Flow Cytometry ; Formazans ; Mesenchymal Stromal Cells ; cytology ; drug effects ; enzymology ; Mice ; Periodontics ; Tetrazolium Salts ; Time Factors

AIMTo determine the effect of histamine on ischemia-induced cellular edema and viability reduction in rat hippocampal slices, and the involved subtypes of histamine receptor in this effect.

METHODSIn vitro ischemic injury of hippocampal slices was induced by oxygen-glucose deprivation (OGD). The slice injury was determined by real-timely measuring the changes of light transmittance (LT) for the cellular edema in CA1 region of the hippocampal slice, and by detecting the product of 2, 3, 5-triphenyltetrazolium chloride (TTC), formazan, for the slice viability. The effect of histamine at various concentrations on the slice injury was observed, and the blockage by antagonists of histamine receptors was also investigated.

RESULTSHistamine (0.01-10 micromol x L(-1)) inhibited the peak value of LT during OGD in hippocampal slices and improved the reduced viability after OGD. Diphenhydramine (0.1-10 micromol x L(-1)), an H1 receptor antagonist, did not affect the effect of histamine, while cimetidine (0.1-10 micromol x L(-1)), an H2 receptor antagonist, partly abolished the protective effect of histamine.

CONCLUSIONHistamine protects hippocampal slices against ischemia-induced cellular edema and viability reduction; this effect might be mediated via, at least partly, H2 receptor.

Animals ; Cell Hypoxia ; Cell Survival ; drug effects ; Cimetidine ; pharmacology ; Diphenhydramine ; pharmacology ; Formazans ; metabolism ; Glucose ; deficiency ; Hippocampus ; drug effects ; metabolism ; pathology ; Histamine ; pharmacology ; Histamine H1 Antagonists ; pharmacology ; Histamine H2 Antagonists ; pharmacology ; Male ; Neuroprotective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the role of mitochondrial calcium uniporter in cardioprotection elicited by ischemic postconditioning (Postcond).

METHODSMale Sprague-Dawley rats were used for Langendorff isolated heart perfusion. The hearts subjected to global ischemia for 30 min followed by 120 min of reperfusion. Left ventricular developed pressure (LVDP), maximal rise/fall rate of left ventricular pressure (± dP/dtmax) were measured. The level of lactate dehydrogenase (LDH) in the coronary effluent was measured spectrophotometrically, the content of formazan of myocardium was also measured at the end of reperfusion.

RESULTCompared to I/R group, Postcond had an significant increase in the mechanical function of the left ventricle, with LDH release reduced and the content of formazan increased. Spermine, the opener of mitochondrial calcium uniporter, deteriorated the mechanical function of left ventricle and decreased the formazan content, and increased LDH release. Ruthenium red, the inhibitor of mitochondrial calcium uniporter, increased the mechanical function of the left ventricle, decreased the LDH release, but the content of formazan was not increased.

CONCLUSIONThe inhibition of mitochondrial calcium uniporter is involved in the mechanisms of ischemic postconditioning.

Animals ; Calcium Channels ; metabolism ; physiology ; Disease Models, Animal ; Formazans ; analysis ; Heart ; physiopathology ; Ischemic Postconditioning ; L-Lactate Dehydrogenase ; analysis ; Male ; Myocardial Reperfusion Injury ; metabolism ; physiopathology ; prevention & control ; Rats ; Rats, Sprague-Dawley