CCl4 Solution Research Articles

Endoplasmic reticulum stress enhances tumor necrosis factor-α expression in rat Kupffer cells to trigger hepatic stellate apoptosis cell through TNFR/caspase-8 pathway

To investigate the role of endoplasmic reticulum (ER)-stress of Kupffer cells (KCs) and KCs-derived tumor necrosis factor-α (TNF-α) in medicating apoptosis of hepatic stellate cell (HSC). Sixty male SD rats were randomized into control group, model group, ER- stress group, depletion group and KCs block group (n=15). The 4 groups of rats were given intraperitoneal injections (twice a week for 8 weeks) of normal saline (2 mg/kg); 40% CCl4 solution (in peanut oil, 2 mg/kg); 40% CCl4 solution (2 mg/kg) and tunicamycin (1 mg/kg); and 40% CCl4 solution (2 mg/kg) and tunicamycin (1 mg/kg) followed by clodronate liposomes (50 mg/kg), respectively. After the treatments, samples of the liver tissue and serum were collected from the rats from the 4 groups to isolate KC cells, which were co-cultured with LX2 cells. In the depletion group, the rats were injected with anti-rat TNFR mAb (0.35 mg/kg) via the portal vein before isolating the KCs. Liver function examination, Eirius red staining, ELISA, immuno- histochemical staining, and RT-PCR were performed to assess the liver function, liver fibrosis, KC phenotypes, expression of the in fl ammatory factors, and the number of active HSC was detected. The isolated KCs were treated with tunicamycin before co-culture with LX2 cells, and ELISA, RT-PCR and Western blot were performed to examine KC phenotypes, in fl ammatory factors, LX2 cell apoptosis and TNFR/caspase8 pathway activity. Compared with the rats in the control group, the rats in the model group had significantly increased ALT and AST levels, Sirius red staining-positive area, and Desmin-positive cells (activated HSCs) (P < 0.05) with significantly lowered number of CD16-positive KCs (M1), and TNF-α protein and mRNA expression (P < 0.05). Compared with those in the model group, the rats in ER-stress group showed significantly decreased ALT and AST levels, Sirius red staining positivity and Desmin-positive cells (P < 0.05) and increased number of CD16-positive KCs and TNF-α expressions (P < 0.05). In the depletion group, compared with the ER-stress group, the rats had significantly increased ALT and AST levels of, Sirius red staining positivity and Desmin-positive cells (P < 0.05) and reduced CD16- positive KCs and TNF-αexpressions (P < 0.05). In the cell co-culture experiment, the model group showed significantly reduced TUNEL-positive LX2 cells, CD16-positive cells, and expressions of TNFR1, cleaved caspase- 8 and cleaved caspase- 3 in the KCs (P < 0.05) with increased Desmin-positive LX2 cells (P < 0.05). Compared with the model group, the ER- stress group exhibited significantly increased TUNEL-positive LX2 cells, CD16-positive cells and expressions of TNFR, cleaved caspase-8 and cleaved caspase-3 in the KCs (P < 0.05) and decreased Desmin-positive LX2 cells (P < 0.05). In the depletion group, blocking TNFR resulted in significantly decreased expressions of cleaved caspase-8 and cleaved caspase-3 compared with those in ER- stress group (P < 0.05) although there was no significant changed in TNFR expression. ER stress of KCs promotes the transformation of KCs towards M1 phenotype and increases the expression of TNF-α, which triggers the apoptosis of HSCs through the TNFR/caspase-8 pathway.

Solvent Effects and Aggregation Phenomena Studied by Vibrational Optical Activity and Molecular Dynamics: The Case of Pantolactone.

Raman and Raman optical activity (ROA), IR, and vibrational circular dichroism (VCD) spectra of (R)- and (S)-pantolactone have been recorded in three solvents. ROA has been employed on water and DMSO solutions, VCD on DMSO and CCl4 solutions. In the last solvent, monomer–dimer equilibrium is present. Due to the low conformational flexibility of the isolated molecule and to the possibility of aggregation, this compound has been used here to test different protocols for computation of the spectroscopic responses taking into account solvent effects. Molecular dynamics (MD) simulations have been carried out together with statistical clustering methods based on collective variables to extract the structures needed to calculate the spectra. Quantum mechanical DFT calculations based on PCM are compared with approaches based on different representations of the solvent shell (MM or QM level). Appropriate treatment of the solvent permits obtaining of good band-shapes, with the added advantage that the MD analysis allows one to take into account flexibility of dimeric structures justifying the broadness of observed bands and the absence of intense VCD couplets in the carbonyl and OH stretching regions.

Impact of donor acidity and acceptor anharmonicity on vc=o spectral shifts in O-H···O=C H-bonded ketone-alcohol complexes: An IR spectroscopic investigation.

O-H···O=C Hydrogen bonding (H-bonding) results in spectral shifts in both νO-H and νC=O modes. A large number of investigations exist in literature that focuses on how the spectral shifts vary with certain properties of the donors and acceptors. However information on how the magnitude of spectral shift is dictated individually by the donor and acceptor is not yet clear to us. Here, IR spectroscopy in room temperature CCl4 solution has been used to investigate how νC=O spectral shifts of ketones in H-bonded complexes with alcohols are influenced by change in donor and acceptor properties. For this purpose 25 number of O-H···O=C H-bonded complexes formed by 5 different ketones and 5 alcohols have been studied. The magnitude of red-shifts shown by the νC=O bands were found to show systematic trends with changing donor and acceptor species. It was found that for a particular ketone, the magnitude of shift increases monotonically with acidity of the alcohols. Spectral shifts were found to increase in a linear fashion with decreasing pKa of the donor alcohols. On the other hand, when the alcohol were kept fixed, the spectral shift was found to be dependent on the CO bond strength of the ketones. We found spectral shifts to linearly increase with increasing anharmonicity constant and decreasing dissociation energy of CO bond. Finally, it has been shown that there exist concomitant correlations of the spectral shifts with donor pKa and acceptor νC=O anharmonicity constant/bond dissociation energy. The relations have been validated for H-bonded complexes of 1,4-cyclohexanedione with the above mentioned five alcohols.

Therapeutic applications of adipose-derived mesenchymal stem cells on acute liver injury in canines

In this study, canine adipose-derived mesenchymal stem cells (cADSCs) therapeutic potential was investigated in artificially induced acute liver injury model by CCl4 in canines. The primary cADSCs cells were cultured and then intravenously administered into the canine animal model. Six cross-breed dogs were divided into three groups including blank control group, CCl4 model group, CCl4 induced cADSCs transplantation group.The results showed that after intraperitoneal injection of CCl4 solution, the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and Albumin (ALB) in peripheral blood of experimental canines confirmed the correct induction of acute liver injury. Moreover, the liver structure showed clear macroscopic damage. The cADSCs were homed in the liver of the administered animals. The AST, ALT and ALB in the peripheral blood rapidly decreased. H&E and PAS histological evaluation showed that both the structure of canine liver tissue and the ability to synthesize hepatic glycogen could be restored to the control level after cADSCs transplantation. Therefore, cADSCs can play a therapeutic role in the recovery of liver injury. Overall, this study demonstrates that the primary cADSCs transplantation into the acute liver injury model induced by intravenous injection can play a certain therapeutic role in the recovery of liver in canines. These results may provide a new treatment idea for acute liver disease in pets clinically.

Free-radical mechanism of the sonochemical reaction of fullerenes C60 and C70 with ethylene glycol in the presence of NaOH

The mechanism of the heterogeneous sonochemical reaction of fullerenes C60 and C70 with ethylene glycol in the presence of NaOH was studied using EPR and UV spectroscopies. As found, the reaction occur via a free-radical mechanism. For the first time in sonochemistry, the signal of the radical NaOCH2CH2O• (a(Na) = a(4H) = 0.061 mT, g = 1.9802; the lifetime in air is 0.5 hours) was registered by the direct EPR method. The kinetics of the NaOCH2CH2O• decay was studied using acceptors of radicals of different nature: DPPH (2,2-diphenyl-1-picrylhydrazyl), galvinoxyl and CCl4. The EPR method revealed that 5,5-dimethyl-1-pyrroline N-oxide (DMPO) does not react with NaOCH2CH2O•. At the sonolysis of the C60 and C70 solutions in CCl4 with ethylene glycol in the presence of NaOH, only the spin adduct DMPO/˙CCl3 was registered. The effect of NaOH, nature of the solvent and dissolved gases, reaction temperature and intensity of ultrasonic radiation on the synthesis of dioxane monoadducts C60 and C70 are discussed.

Photochemistry of dithiophosphinate Ni(S2P(i-Bu)2)2 complex in CCl4. Transient species and TD-DFT calculations

Femtosecond spectroscopy and nanosecond laser flash photolysis were used to study the photophysical and photochemical transformations of the bis-diisobutyl-dithiophosphinate Ni(II) complex (Ni(S2P(i-Bu)2)2 = Ni(dtpi)2, where dtpi− ≡ −S2P(i-Bu)2) in CCl4 solutions. The radiation of second harmonic (405 nm) of Ti:Sapphire laser transfers the Ni(dtpi)2 complex to an excited 1LMCT state. Its decay in CCl4 is described by three exponents with time constants 0.58, 2.0 and ˜150 ps. The first process apparently involves the fast transitions from 1LMCT state to 3LMCT due to the intersystem crossing (ISC) and then to lower-lying "hot" 3LF (Ligand Field) state. The second time constant, most likely, corresponds to the vibrational cooling of this "hot" 3LF state. And the third slow process is the transition from 3LF state to ground state (1GS).The quantum yield of photochemical transformation under the 405 irradiation is close to zero, so the study of photochemistry was performed with a nanosecond flash photolysis at 308 nm. In this case an electron transfer from the excited Ni(dtpi)2 complex to a solvent molecule leads to the appearance of primary intermediate, the [ClNi(dtpi)(dtpi)] complex, in which a dtpi radical is coordinated with a nickel ion via one sulfur atom. In the fast reaction with Ni(dtpi)2, this complex forms a long-lived dimer ClNi(dtpi)(dtpi)[Ni(dtpi)2]. This intermediate for a few hundred microseconds decays in the reaction of recombination with the formation of (dtpi)2 disulphide and unstable ClNi(dtpi) complex. The insoluble NiCl2 salt falled in CCl4 as the sediment due to the reaction of two ClNi(dtpi) complexes. The quantum chemical calculations allowed to determine the geometry of the intermediate complexes arising in the photochemistry of Ni(S2P(i-Bu)2)2 complex.

Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of the Volatile Oil of Cichorium Glandulosum Boiss et Huet and its Effects on Carbon Tetrachloride-Induced Liver Fibrosis in Rats.

BackgroundThis study aimed to use gas chromatography-mass spectrometry (GC-MS) to identify the chemical constituents of volatile oil extracted by steam distillation from Cichorium glandulosum Boiss et Huet (CG), a traditional Uyghur medicine, and to investigate its effects on carbon tetrachloride (CCl4)-induced hepatic fibrosis in rats.Material/MethodsSprague-Dawley rats (n=60) included six groups: the control group (n=10), untreated model group (n=10), the volatile oil of CG high-dose group (0.15 ml/kg) (n=10), the volatile oil of CG medium-dose group (0.10 ml/kg) (N=10), the volatile oil of CG low-dose group (0.05 ml/kg) (n=10), and the silybin-treated group (0.20 ml/kg) (n=10). Rats given the essential oil extract of CG by intragastric administration, and then subcutaneously injected with a solution of CCl4 in olive oil to create the rat model of hepatic fibrosis. Serum samples were analyzed for markers of liver function, including aspartate transaminase (AST), alanine transaminase (ALT), malondialdehyde (MDA), hydroxyproline (Hyp), γ-glutamyl transpeptidase (γ-GT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and albumin (Alb). Histology and immunohistochemistry were performed on rat liver tissue.ResultsThirty-eight compounds were identified from the volatile oil of CG (total, 98.058%), with terpenoids, including citronellol, being the most abundant. In the animal model of liver fibrosis, all doses of volatile oil of CG significantly reduced the serum levels of AST, ALT, MDA, Hyp, γ-GT, LDH, ALP, and Alb.ConclusionsGC-MS identified the components of the volatile oil of CG, which included citronellol. Treatment with volatile oil of CG reduced liver fibrosis in a rat model.

Micellar propolis nanoformulation of high antioxidant and hepatoprotective activity

The present study reports a promising antioxidant protection by a recently developed micellar propolis formulation, against oxidative stress in in vitro and in vivo models of toxicity. The formulation, based on poplar propolis encapsulated in poly(ethylene oxide)–β-poly(propylene oxide)–β-poly(ethylene oxide) triblock copolymer (PEO26–PPO40–PEO26) micelles is characterized by small size (Dh=20nm), enhances aqueous solubility and good colloidal stability. In vitro, propolis-loaded PEO26–PPO40–PEO26 micelles (20–100μg/ml) significantly increased the cell viability of human hepatoma HepG2 cells, subjected to H2O2-induced cell injury (0.1mM, 1h). Antioxidant activity and protection of the micellar propolis were evaluated in a model of carbon tetrachloride-induced hepatotoxicity in rats (10% CCl4 solution, 1.25ml/kg, p.o.) by measurement of non-enzyme (malondialdehyde and glutathione) and enzyme (catalase and superoxide dismutase) biomarkers of oxidative stress. Clinic observations, hematological, biochemical parameters and histological analysis were also performed. In vivo, micellar propolis (20mg/kg b.w., p.o., 14 days) ameliorated CCl4-induced acute liver injury in rats. The oral administration of micellar propolis significantly prevented serum transaminase increases, as well as brought the levels of malondialdehyde, glutathione, and antioxidant enzymes catalase and superoxide dismutase toward the controls levels. Therefore, PEO26–PPO40–PEO26 micelles could be considered as a promising oral delivery system of propolis against oxidative stress injury in liver cells.

NIR spectra simulation of thymol for better understanding of the spectra forming factors, phase and concentration effects and PLS regression features

Near-infrared spectroscopy (NIRS) is an effective analytical/quality control tool in various appliances, i.e. in phytopharmaceutical industry. While multivariate analysis gives NIRS the desired level of analytical performance it lacks in providing deeper physical insights. Quantum mechanical (QM) simulation of NIR spectra is becoming feasible for complex molecules in the present days. The usefulness of QM simulation in NIRS surpasses that in IR region as NIR spectra are intrinsically complex as a result of anharmonic effects; yet QM investigations in NIRS remain rare due to practical limitations. QM provides detailed band assignments, far exceeding the capability of classical spectroscopic methods, but also offers unveiling the influential factors in the chemometric models. In the present work we investigate NIR spectrum of thymol, a constituent of Thymi herba used in traditional medicine. Experimental part compares the NIR spectra of thymol in solid state, melted (neat liquid) and in CCl4 solutions of different concentrations. The analysis unveils the spectral regions of strongly varying sensitivity level to the sample state; two regions (6000–5600 cm−1 and 4490–4000 cm−1) are identified as remaining largely invariant under the sample state. The band assignments and plotted density of modal contribution visualize generalized and categorized NIR spectra forming factors of thymol. A principle relationship with the regression coefficients plot is established, demonstrating that the NIR bands which retain high insensitivity to the intermolecular interactions give the most influence in the PLS regression model of thymol.

Protective effects of Liuweiwuling tablets on carbon tetrachloride-induced hepatic fibrosis in rats

BackgroundLiuweiwuling tablets (LWWL) are an herbal product that exerts remarkable effects on liver protection and aminotransferase levels, and they have been approved by the Chinese State Food and Drug Administration (CFDA). Clinical studies have found that LWWL can inhibit collagen production and reduce the levels of liver fibrosis markers in the serum. Thus, LWWL is expected to have beneficial effects in the treatment of liver fibrosis. The purpose of this study was to evaluate the pharmacological effects of LWWL.MethodsHepatic fibrosis was induced in rats via carbon tetrachloride (CCl4) treatment. The rats were treated twice weekly for 8 weeks with either 2 mL·kg− 1 body weight of a 50% solution of CCl4 in olive oil or olive oil alone by oral gavage. A subset of rats received daily intraperitoneal injections of either colchicine (0.2 mg/kg per day), LWWL (0.4, 1.6, or 6.4 g/kg per day), or vehicle (N = 12 for all groups) during weeks 9–12. The rats were sacrificed after 12 weeks. Pathological changes in hepatic tissue were examined using hematoxylin and eosin (H&E) and Sirius Red staining. Immunohistochemistry was performed to observe α-smooth muscle actin (α-SMA) and collagen type I (collagen I) protein expression. Western blotting was also used to detect α-SMA protein expression. Real-time quantitative reverse-transcription polymerase chain reaction (RT-qPCR) was used to detect transforming growth factor-1 (TGF-β1), platelet-derived growth factor (PDGF), tissue inhibitor of metalloproteinase-1 (TIMP1), and tissue inhibitor of metalloproteinase-2 (TIMP2) mRNA expression.ResultsLWWL significantly reversed histological fibrosis and liver injury, reduced the hydroxyproline content in liver tissue, and decreased α-SMA and collagen I expression. LWWL also suppressed hepatic stellate cell (HSC) activation by reducing the expression of the profibrogenic factors TGF-β1 and PDGF. The expression levels of TIMP1 and TIMP2, which regulate extracellular matrix (ECM) degradation, were decreased after CCl4 injury in LWWL-treated rats.ConclusionsThese data suggest that LWWL may serve as a promising therapeutic agent to reduce fibrogenesis.

Volumetric, isentropic compressibility and viscosity coefficient studies of binary solutions involving amides as a solute in aqueous and CCl4 solvent systems at 298.15 K

The experimental measurements of the density, speed of sound and viscosity coefficient in binary solutions involving water and CCl4 as solvents and formamide, N-methylformamide, N, N-dimethylformamide, N-methylacetamide and N, N-dimethylacetamide as solute in the concentration range (0.00992 mol·kg−1 to 1.07890 mol·kg−1) at 298.15 K are reported. The data are used to obtain the isentropic compressibility (βs) of solutions and Jones-Dole viscosity B and D coefficients for solutes. The derived properties like apparent molar volume (Vϕ) and apparent molar isentropic compressibility (Kϕ) of amides at different concentrations are evaluated. The data of limiting apparent molar volume (Vϕ0) and apparent molar isentropic compressibility (Kϕ0) for amides in both solvent systems (H2O and CCl4) and their concentration variation are examined to study the effect of intermolecular H-bond formation (for the amide molecules), hydrophobic interaction effect in water and amide-CCl4 interactions. It has been observed that there is loss of volume and compressibility of amide molecules in transferring them from pure liquid state to water and gain in transferring to CCl4 solutions (non-aqueous solvent) except for dimethylacetamide. The transfer volumes and compressibilities from CCl4 to water are negative and are attributed to H bond formation between solute molecules. The viscosity B coefficients for the amides are found to be high positive in water while they are of small magnitude in CCl4 medium. All these results are discussed on the basis of solute-solvent interaction, hydrophobic interaction in water and H-bond formation possibilities in CCl4. It is proposed that, the dissolution of dimethylformamide in water takes place substitutionally in water cavities with very little volume change.

Sesquiterpenoids from the root of Panax Ginseng protect CCl4–induced acute liver injury by anti-inflammatory and anti-oxidative capabilities in mice

The oxidative stress and inflammatory response play an important role in carbon tetracholoride (CCl4)-induced acute liver injury. In this work, sesquiterpenoids from the root of Panax Ginseng (SPG) were prepared, and then the hepatoprotective effects of SPG against CCl4-induced acute liver injury were investigated and the underlying mechanism was explored in mice. All mice were divided into four groups: the control, CCl4 and SPG (2.5 and 10 mg/kg, dissolved in soybean oil, i.g.) groups. All mice were given continuous administration for 7 days, and injected with CCl4 (0.1 mL/10 g body weight 0.2% CCl4 solution in soybean oil, i.p.) 1 h after the end of the administration except the control group. Mice were sacrificed 24 h post-CCl4 injection. The results indicated that SPG significantly reduced the increasement of serum AST and ALT levels induced by CCl4-treatment. And the histopathological analysis revealed that SPG treated mice had normal liver architecture and no necrosis. The decreased activities of SOD, GSH and CAT, and increased MDA level were inhibited by SPG treatment. At the same time, the levels of TNF-α, IL-1β and IL-6 were significantly decreased by SPG treatment. SPG treatment also reduced the heptic protein expressions of NF-κB p65, COX-2, MAPK p38, ERK and JNK in the liver. These fingdings demonstrated that SPG exhibited strong hepatoprective effect on the CCl4-induced acute liver injury, which was related to anti-oxidantive and anti-inflammatory capabilities; and the anti-inflammatory effect of SPG might mediated by the NF-κB and MAPKs signaling pathways. Taken together, SPG might be a potential material for drug and functional food development against chemical hepatic injury.

The Effect of Molecular Iodine on Singlet-Oxygen Luminescence in Tetrachloromethane

The spectral properties of singlet-oxygen luminescence at the 1Δ g → 3Σ g transition in the presence of rose Bengal as a photosensitizer are analyzed. The effect of iodine in solution in CCl4 on the efficiency of singlet-oxygen generation and on the structure of singlet-oxygen luminescence is shown. The results of studies with tetrachloromethane are compared with the results obtained with other solvents.

Identification of Microwave Selective Heating Effort in an Intermolecular Reaction with Hammett Linear Relationship as a Molecular Level Probe

Background: The origin of the microwave acceleration organic reactions is still not completely clear. According to the selective heating mechanism of microwave irradiation, the heat accumulated in the polar reactants may generate localized superheating, resulting in acceleration of the certain reactions. Methods: In this study, the Hammett linear relationship of a “one-pot” saponification with a series of mixed butyl substituted benzoates was selected as a molecular level probe to explore the microwave selective heating effects in intermolecular reactions. If there is a “hot spots” effect, the Hammett linear relationship will be distorted. Heating curves at 20 W of microwave power for 0.1 mol/L solution of butyl 4-nitrobenzoate, butyl 4-chlorobenzoate, butyl benzoate, butyl 4-methylbenzoate, and 4- methoxybenzoate solutions in solvent CCl4 show that butyl 4-nitrobenzoate can act as ‘molecular radiators' in the reaction mixture. We performed this “one-pot” saponification in three solvent systems with different polarity to identify this effect. The microwave experiments were performed under the constant temperature mode and constant power mode. Results: In polar solvent butanol, the Hammett linear relationship does not change. Large amount of solvent absorbs the microwave energy and shields the differences of the microwave absorbing ability among different butyl substituted benzoates. In the medium polar solvent THF, the strong polar reactant butyl 4-nitrobenzoate can play as ‘molecular radiators’ which means that its instance temperature is higher than the surrounding. In this case, the Hammett linear relationship remains unchanged under microwave irradiation in both constant temperature mode and constant power mode. However, there is a rate acceleration under microwave irradiation (measured as the reaction constant ρ is increased). Finally, we attempted to conduct the reactions in nonpolar solvent CCl4. Unfortunately, the reactions did not happen due to poor solubility of butyl substituted benzoates. Conclusion: In this study, we found that there is no measurable effective temperature gradient of different polar reactants but a whole acceleration in reaction rate. The acceleration is attributed to the thermal effect. Keywords: Hammett equation, hot spot, microwave effect, microwave irradiation, molecular radiators, selective heating.

A Quick Method for Assessing the Activity of Shungite Filler in Elastomer Composite Materials

A quick method for assessing elastomer-to-shungite bond strength is presented. An Instron 3365 tensile testing machine was used to measure the force needed to peel away a cotton strip impregnated with a rubber solution in CCl4 from the surface of shungite sheets. The rubbers included butyl rubber (BR), nitrile butadiene rubber (SKN-18), polyisoprene (SKI-3), a copolymer of ethylene and vinyl acetate (CEVA), polychloroprene (PC), chlorosulphonated polyethylene (CSPE), and chlorinated butyl rubber (CBR). The nature of the obtained results depends on elastomer functionality. Smooth curves of the dependence of the measured stress on the distance between the clamps of the tensile testing machine were obtained for elastomers not having functional groups interacting with the shungite, e.g. for BR; on the curves for elastomers interacting with the shungite, e.g. for PC, a series of peaks was observed on the curves. The obtained results make it possible to predict the strength of elastomer composite materials containing shungite.

Hepatocyte-like Versus Mesenchymal Stem Cells in CCl4-induced Liver Fibrosis.

It is still a matter of debate as to whether in vitro mesenchymal stem cell (MSC)-derived hepatocytes may efficiently repopulate a host liver to provide adequate functional substitution. The aim of this study is to assess the efficacy and consistency of in vitro hepatic differentiation from Wharton jelly-derived MSCs, and to validate their therapeutic potential in experimentally induced liver fibrosis compared with nondifferentiated MSCs. Forty adult male albino rats were divided into 4 main groups: (I) normal control group; (II) carbon tetrachloride (CCl4)-treated group (injected CCl4 solution twice a week for 8 wk); (III) MSC-treated group (a single intravenous dose of MSCs from human umbilical cord at the fourth week of induction of fibrosis); and (IV) hepatocyte-like stem cells (HLCs)-treated group (a single intravenous dose of MSCs after in vitro conversion to hepatocyte at the fourth week of induction of fibrosis). Portal blood flow velocity and resistance, serum alanine transaminase, aspartate transaminase, albumin, and total bilirubin were measured. Liver homogenate was prepared for malondialdehyde, superoxide dismutase (SOD), nitric oxide (measured as nitrites), and TGFβ (transforming growth factor beta) assessment. Assessment of human cells homing into liver rat and their function was performed using immunohistochemistry for detection of human hepatocytes and α-fetoprotein antigens. Significant elevation of serum alanine transaminase, aspartate transaminase, and bilirubin, liver malondialdehyde, nitrites, TGFβ, fibrotic score, and significant reduction in serum albumin, liver SOD, and portal flow velocity in the CCl4-treated group were found when compared with normal rats. All these parameters significantly reversed in MSC-treated and hepatocyte-treated groups when compared with the CCl4-treated group. The MSC-treated group shows statistically better results in most liver function and oxidation parameters when compared with the HLC-treated group. Human MSCs can differentiate in vitro into functional HLCs. Transplantation of both MSCs and HLCs was feasible and effective in a liver fibrosis rat model. However, MSCs were better in regaining liver function. Future studies should address strategies to improve long-term implantation of MSCs and HLCs in the host liver.

Antagonistic Interplay Between an Intermolecular CH···O and an Intramolecular OH···O Hydrogen Bond in a 1:1 Complex Between 1,2-Cyclohexanedione and Chloroform: A Combined Matrix Isolation Infrared and Quantum Chemistry Study.

Matrix isolation infrared spectra of a weak C-H···O hydrogen-bonded complex between the keto-enol form of 1,2-cyclohexanedione (HCHD) and chloroform have been measured. The spectra reveal that the intramolecular O-H···O H-bond of HCHD is weakened as a result of complex formation, manifesting in prominent blue shift (∼23 cm-1) of the νO-H band and red shifts (∼7 cm-1) of νC═O bands of the acceptor (HCHD). The νC-H band of donor CHCl3 undergoes a large red shift of ∼33 cm-1. Very similar spectral effects are also observed for formation of the complex in CCl4 solution at room temperature. Our analysis reveals that out of several possible iso-energetic conformational forms of the complex, the one involving antagonistic interplay between the two hydrogen bonds (intermolecular C-H···O and intramolecular O-H···O) is preferred. The combined experimental and calculated data presented here suggest that in condensed media, conformational preferences are guided by directional hyperconjugative charge transfer interactions at the C-H···O hydrogen bonding site of the complex.

IR spectroscopic study of H complexes of dioxolane derivatives with methanol in CCl4 solutions

The effect of the formation of H complexes of some dioxolane derivatives with methyl alcohol on the parameters of stretching bands of the OH group is studied. The observed changes in the spectral and energy characteristics of the complexes are due to the inductive effect of the introduced structural fragments on the equilibrium electron configuration of the COC group in position 1 of the proton acceptor. Based on the results obtained, the authors make the conclusion that the compounds studied are weak proton acceptors.

Resveratrol alleviates FFA and CCl4 induced apoptosis in HepG2 cells via restoring endoplasmic reticulum stress.

Cell apoptosis often induces inflammation and injury in the liver, with endoplasmic reticulum (ER) stress as the most possible reason. Resveratrol (RSV) has been shown to prevent hepatic steatosis and alleviate apoptosis, however, the exact mechanisms underlying the effects still need to be explored. Here we co-cultured HepG2 cells with free fatty acid (FFA) solution (oleic acid: palmitic acid = 2:1) and then exposed to a carbon tetrachloride (CCl4) solution to induce apoptosis. To evaluate the therapeutic effects, RSV (2.5 μM, 5 μM, 10 μM) was added to the cells. Results showed that HepG2 cells co-cultured with FFA exhibited lipid infiltration and were susceptible to apoptosis upon exposure to the CCl4 solution. The expression of molecules related to apoptosis (Caspases, Bcl-2/Bax) and ER stress (GRP78, IRE1, ATF6, PERK, et al.) was all significantly decreased upon RSV treatment. We further inhibited GRP78 by siRNA, results showed that the anti-apoptotic effect of RSV still maintained under GRP78 siRNA condition. Our data demonstrated that lipid accumulated HepG2 cells were susceptible to injury, and RSV could improve apoptosis in FFA and CCl4 stressed cells, which partially via restoring ER function.

Temperature Drift of Conformational Equilibria of Butyl Alcohols Studied by Near-Infrared Spectroscopy and Fully Anharmonic DFT.

Conformational isomerism of aliphatic alcohols with respect to the internal rotation of C-O(H) group and its impact on near-infrared (NIR) spectra has been known in the literature. However, no attempt has ever been made to investigate systematically whether and how the conformational flexibility of the aliphatic chain determines the observed NIR data of aliphatic alcohols. In the present study NIR spectra of four kinds of butyl alcohols, 1-butanol, 2-butanol, isobutanol, and tert-butyl alcohol, were investigated in diluted (0.1 M) CCl4 solutions. The experimental NIR spectra of butyl alcohols were accurately reproduced and explained in a fully anharmonic DFT study by means of generalized second-order vibrational perturbation theory (GVPT2). Entire conformational populations were taken into account in each case. On the basis of the theoretical study, influences of conformational flexibility with respect to internal rotations not only about the C-O bond, but also about the C-C bonds have been well evidenced in the experimental spectra. The conformational isomerism affects significantly the shape of NIR spectra. The temperature-dependent NIR spectra of butyl alcohols show changes in the band shape and a blue-shift of the overtone band due to the stretching mode of free OH group, and its intensity decreases with increasing temperature. These effects can be closely monitored by two-dimensional correlation spectroscopy (2D-COS). In this work, the experimental 2D-COS patterns have been successfully reproduced, based on DFT calculated NIR spectra of conformational isomers of the studied molecules and their Boltzmann coefficients over the corresponding temperature range. Thus, the experimentally observed effects are fully reflected in the DFT study, which leads to the conclusion that the main factor in the temperature-dependent spectral changes of 2νOH band of aliphatic alcohols in the diluted phase, where no self-association occurs, is played by the changes in the relative population of their conformational isomers.