A review of cinnabar (HgS) and/or realgar (As4S4)-containing traditional medicines

ETHNOPHARMOCOLOGICAL RELEVANCE

Herbo-metallic preparations have a long history in the treatment of diseases, and are still used today for refractory diseases, as adjuncts to standard therapy, or for economic reasons in developing countries.

AIM OF THE REVIEW

This review uses cinnabar (HgS) and realgar (As₄S₄) as mineral examples to discuss their occurrence, therapeutic use, pharmacology, toxicity in traditional medicine mixtures, and research perspectives.

MATERIALS AND METHODS

A literature search on cinnabar and realgar from PubMed, Chinese pharmacopeia, Google and other sources was carried out. Traditional medicines containing both cinnabar and realgar (An-Gong-Niu-Huang Wan, Hua-Feng-Dan); mainly cinnabar (Zhu-Sha-An-Shen Wan; Zuotai and Dangzuo), and mainly realgar (Huang-Dai Pian; Liu-Shen Wan; Niu-Huang-Jie-Du) are discussed.

RESULTS

Both cinnabar and realgar used in traditional medicines are subjected to special preparation procedures to remove impurities. Metals in these traditional medicines are in the sulfide forms which are different from environmental mercurials (HgCl₂, MeHg) or arsenicals (NaAsO₂, NaH₂AsO₄). Cinnabar and/or realgar are seldom used alone, but rather as mixtures with herbs and/or animal products in traditional medicines. Advanced technologies are now used to characterize these preparations. The bioaccessibility, absorption, distribution, metabolism and elimination of these herbo-metallic preparations are different from environmental metals. The rationale of including metals in traditional remedies and their interactions with drugs need to be justified. At higher therapeutic doses, balance of the benefits and risks is critical. Surveillance of patients using these herbo-metallic preparations is desired.

CONCLUSION

Chemical forms of mercury and arsenic are a major determinant of their disposition, efficacy and toxicity, and the use of total Hg and As alone for risk assessment of metals in traditional medicines is insufficient.

[Effect of Zuotai and HgS on gene expression of drug-metabolizing enzymes in livers of mice]

Zuotai and cinnabar(96%HgS) are contained in many traditional medicines. To examine their potential effects on drug metabolism genes, mice were orally given Zuotai or HgS at doses of 10, 30, 100, 300 mg•kg⁻¹ for 7 days. HgCl2(33.6 mg•kg⁻¹) was gavaged for control. Twenty-four hour later after the last administration, livers were collected, and expressions of genes related to metabolic enzymes and transporters were examined. Zuotai and HgS had no effects on major phase-1, phase-2 and transporter genes; HgCl2 increased the expressions of CYP2B10, CYP4A10, OATP1A4, UGT1A1, UGT2A3, SULT1A1, SULT2A1, MRP1, MRP3 and MRP4; expression of OATP1A1 was decreased by HgCl2, but not by Zuotai and HgS. Therefore, Zuotai and HgS have different adverse effects on drug-metabolizing genes from HgCl2.

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice

Objectives

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice.

Methods

Mice were given DNLA at doses of 10–80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis.

Key findings

Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα.

Conclusions

DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders.

Atorvastatin alters the expression of genes related to bile acid metabolism and circadian clock in livers of mice

Aim

Atorvastatin is a HMG-CoA reductase inhibitor used for hyperlipidemia. Atorvastatin is generally safe but may induce cholestasis. The present study aimed to examine the effects of atorvastatin on hepatic gene expression related to bile acid metabolism and homeostasis, as well as the expression of circadian clock genes in livers of mice.

Methods

Adult male mice were given atorvastatin (10, 30, and 100 mg/kg, po) daily for 30 days, and blood biochemistry, histopathology, and gene expression were examined.

Results

Repeated administration of atorvastatin did not affect animal body weight gain or liver weights. Serum enzyme activities were in the normal range. Histologically, the high dose of atorvastatin produced scattered swollen hepatocytes, foci of feathery-like degeneration, together with increased expression of Egr-1 and metallothionein-1. Atorvastatin increased the expression of Cyp7a1 in the liver, along with FXR and SHP. In contract, atorvastatin decreased the expression of bile acid transporters Ntcp, Bsep, Ostα, and Ostβ. The most dramatic change was the 30-fold induction of Cyp7a1. Because Cyp7a1 is a circadian clock-controlled gene, we further examined the effect of atorvastatin on clock gene expression. Atorvastatin increased the expression of clock core master genes Bmal1 and Npas2, decreased the expression of clock feedback genes Per2, Per3, and the clock targeted genes Dbp and Tef, whereas it had no effect on Cry1 and Nr1d1 expression.

Conclusion

Repeated administration of atorvastatin affects bile acid metabolism and markedly increases the expression of the bile acid synthesis rate-limiting enzyme gene Cyp7a1, together with alterations in the expression of circadian clock genes.

Dendrobium nobile Lindl alkaloid, a novel autophagy inducer, protects against axonal degeneration induced by Aβ25-35 in hippocampus neurons in vitro

AIMS

Axonal degeneration is a pathological symbol in the early stage of Alzheimer's disease (AD), which can be triggered by amyloid-β (Aβ) peptide deposition. Growing evidence indicates that deficit of autophagy eventually leads to the axonal degeneration. Our previous studies have shown that Dendrobium nobile Lindl alkaloid (DNLA) had protective effect on neuron impairment in vivo and in vitro; however, the underlying mechanisms is still unclear.

METHODS

We exposed cultured hippocampus neurons to Aβ_25-35 to investigate the effect of DNLA in vitro. Axonal degeneration was evaluated by immunofluorescence staining and MTT assay. Neurons overexpressing GFP-LC3B were used to measure the formation of autophagosome. Autophagosome-lysosome fusion, the lysosomal pH, and cathepsin activity were assessed to reflect autophagy process. Proteins of interest were analyzed by Western blot.

RESULTS

DNLA pretreatment significantly inhibited axonal degeneration induced by Aβ_25-35 peptide in vitro. Further studies revealed DNLA treatment increased autophagic flux through promoting formation and degradation of autophagosome in hippocampus neurons. Moreover, enhancement of autophagic flux was responsible for the protective effects of DNLA on axonal degeneration.

CONCLUSIONS

DNLA prevents Aβ_25-35 -induced axonal degeneration via activation of autophagy process and could be a novel therapeutic target.

Adaptive laser shock micro-forming for MEMS device applications

Laser shock micro-forming is a non-thermal laser forming method that uses laser-induced shockwave to modify surface properties and to adjust shapes and geometry of work pieces. The magnitude and spatial distribution of the laser-induced shockwaves depend on the energy profiles of the laser beam focused on sample surfaces. In this paper, we present an adaptive optical technique to engineer spatial profiles of laser beams to control the shapes, sizes, and locations of the laser-induced shockwaves and the resulting forming features. Using a spatial light modulator, this adaptive laser beam forming tool was used to process free-standing MEMS structures in aluminum, which has led to highly uniform forming features. Shockwave simultaneously excited by multiple laser beams generated by the spatial light modulator and its effects on the micro-forming process were also studied. The results presented in this paper show that the adaptive optics laser beam forming is an effective and flexible method to generate shockwave with various shapes and sizes of wavefront and at multiple locations for laser processing at microscales.

Zero-gap semiconductor to excitonic insulator transition in Ta2NiSe5

The excitonic insulator is a long conjectured correlated electron phase of narrow-gap semiconductors and semimetals, driven by weakly screened electron–hole interactions. Having been proposed more than 50 years ago, conclusive experimental evidence for its existence remains elusive. Ta₂NiSe₅ is a narrow-gap semiconductor with a small one-electron bandgap E_G of <50 meV. Below T_C=326 K, a putative excitonic insulator is stabilized. Here we report an optical excitation gap E_op ∼0.16 eV below T_C comparable to the estimated exciton binding energy E_B. Specific heat measurements show the entropy associated with the transition being consistent with a primarily electronic origin. To further explore this physics, we map the T_C–E_G phase diagram tuning E_G via chemical and physical pressure. The dome-like behaviour around E_G∼0 combined with our transport, thermodynamic and optical results are fully consistent with an excitonic insulator phase in Ta₂NiSe₅.

The nature of an insulating phase in Ta₂NiSe₅ is an open question. Here, Lu et al. report transport, thermodynamic and optical evidences being fully consistent with an excitonic insulator phase in this material.

Dysregulation of metallothionein and circadian genes in human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the major threat to human health, and disruption of circadian clock genes is implicated in hepatocarcinogenesis. This study examined the dysregulation of metallothioneins and circadian genes in achieved human HCC (n = 24), peri-HCC tissues (n = 24) as compared with normal human livers (n = 36). Total RNA was extracted and reverse transcribed. Real-time RT-qPCR was performed to determine the expression of genes of interest. The results demonstrated the downregulation of metallothionein-1 (MT-1), MT-2, and metal transcription factor-1 (MFT-1) in human HCC as compared with Peri-HCC and normal tissues. MTs are a biomarker for HCC and have typical circadian rhythms; the expression of major circadian clock genes was also determined. HCC produced a dramatic decrease in the expression of core clock genes, circadian locomotor output cycles kaput (Clock) and brain and muscle Arnt-like protein 1 (Bmal1), and decreased the expression of the clock feedback control genes, Periods (Per1, Per2) and Cryptochromes (Cry1, Cry2). On the other hand, the expression of clock target genes nuclear orphan receptor factor protein (Nr1d1) and D-box-binding protein (Dbp) was upregulated as compared with Peri-HCC and normal livers. Peri-HCC also had mild alterations in these gene expressions. In summary, the present study clearly demonstrated the dysregulation of MTs and circadian clock genes in human HCC, which could provide the information of targeting MT and circadian clock in HCC management.

Investigation on self-absorption at reduced air pressure in quantitative analysis using laser-induced breakdown spectroscopy

The self-absorption at reduced air pressure for quantitative analysis of Mn and Cu elements in steel using laser-induced breakdown spectroscopy was investigated. The calibration curves of Mn and Cu elements at the air pressures of 100, 80, 50, 20, and 1 kPa were studied. The results show that, the nonlinearity of calibration curves which caused by self-absorption effects at atmosphere could be significantly improved by reducing the air pressure to 1 kPa, and the coefficients of determination (R²) of linear calibration curves of Mn and Cu lines are all higher than 0.99. The further study explored that the reason for the improvement was that the induced plasma became low density and the self-absorption coefficient was close to 1 when the air pressure reduced to 1 kPa.

De novo transcriptome analysis of tobacco seedlings and identification of the early response gene network under low-potassium stress

Tobacco is an economically important crop, and its potassium content can greatly affect the quality of tobacco leaves. However, the molecular mechanism involved in potassium starvation in tobacco has not been elucidated to date. In this study, Illumina (Solexa) sequencing technology was used to analyze the transcriptome of tobacco seedlings under low-potassium stress for 6, 12, and 24 h. After analysis, 107,824 assembled unigenes were categorized into 57 GO functional groups, and 31,379 unigenes (29.08%) were clustered into 25 COG categories. A total of 9945 genes were classified into 233 KEGG pathways, and 15,209 SSRs were found among the 107,824 unigenes. Between the two samples, 1034 genes were differentially expressed. Twelve randomly selected gene expression levels were analyzed by quantitative RT-PCR, and the results were highly consistent with those obtained by Solexa sequencing. Our results provide a comprehensive analysis of the gene-regulatory network of tobacco seedlings under low-potassium stress.

Sensitive determinations of Cu, Pb, Cd, and Cr elements in aqueous solutions using chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy

In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R² of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 μg/mL for the unitary solution, and in the range of 0.025-0.420 μg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

Characterizing novel metabolic pathways of melatonin receptor agonist agomelatine using metabolomic approaches

Agomelatine (AGM), an analog of melatonin, is a potential agonist at melatonin receptors 1/2 and a selective antagonist at 5-hydroxytryptamine 2C receptors. AGM is widely used for the treatment of major depressive episodes in adults. However, multiple adverse effects associated with AGM have been reported in clinical practice. It is little known about AGM metabolism in vitro and in vivo, although metabolism plays a pivotal role in its efficacy and safety. To elucidate metabolic pathways of AGM, we systemically investigated AGM metabolism and its bioactivation in human liver microsomes (HLM) and mice using metabolomic approaches. We identified thirty-eight AGM metabolites and adducts, among which thirty-two are novel. In HLM, we uncovered five GSH-trapped adducts and two semicarbazide-trapped aldehydes. Moreover, we characterized three N-acetyl cysteine conjugated-AGM adducts in mouse urine and feces, which were formed from the degradation of AGM_GSH adducts. Using recombinant CYP450 isoenzymes and chemical inhibitors, we demonstrated that CYP1A2 and CYP3A4 are primary enzymes contributing to the formation of AGM_GSH adducts and AGM_hydrazones. This study provided a global view of AGM metabolism and identified the novel pathways of AGM bioactivation, which could be utilized for further understanding the mechanism of adverse effects related to AGM and possible drug-drug interactions.

Background removal in soil analysis using laser- induced breakdown spectroscopy combined with standard addition method

The matrix effect of powder samples, especially for soil samples, is significant in laser-induced breakdown spectroscopy (LIBS), which affects the prediction accuracy of the element concentration. In order to reduce this effect of the soil samples in LIBS, the standard addition method (SAM) based on background removal by wavelet transform algorithm was investigated in this work. Five different kinds of certified reference soil samples (lead (Pb) concentrations were 110, 283, 552, 675, and 1141 ppm, respectively) were used to examine the accuracy of this method. The root mean square error of prediction (RMSEP) was more than 303 ppm by using the conventional calibration method. After adoption of SAM with background removal by wavelet transform algorithm, the RMSEP was reduced to 25.7 ppm. Therefore, the accuracy of the Pb element was improved significantly. The mechanism of background removal by wavelet transform algorithm based on SAM is discussed. Further study demonstrated that this method can also improve the predicted accuracy of the Cd element.

The Tibetan medicine Zuotai influences clock gene expression in the liver of mice

Background. The circadian clock is involved in drug metabolism, efficacy and toxicity. Drugs could in turn affect the biological clock as a mechanism of their actions. Zuotai is an essential component of many popular Tibetan medicines for sedation, tranquil and “detoxification,” and is mainly composed of metacinnabar (β-HgS). The pharmacological and/or toxicological basis of its action is unknown. This study aimed to examine the effect of Zuotai on biological clock gene expression in the liver of mice. Materials and methods. Mice were orally given Zuotai (10 mg/kg, 1.5-fold of clinical dose) daily for 7 days, and livers were collected every 4 h during the 24 h period. Total RNA was extracted and subjected to real-time RT-PCR analysis of circadian clock gene expression. Results. Zuotai decreased the oscillation amplitude of the clock core gene Clock, neuronal PAS domain protein 2 (Npas2), Brain and muscle Arnt-like protein-1 (Bmal1) at 10:00. For the clock feedback negative control genes, Zuotai had no effect on the oscillation of the clock gene Cryptochrome (Cry1) and Period genes (Per1–3). For the clock-driven target genes, Zuotai increased the oscillation amplitude of the PAR-bZip family member D-box-binding protein (Dbp), decreased nuclear factor interleukin 3 (Nfil3) at 10:00, but had no effect on thyrotroph embryonic factor (Tef); Zuotai increased the expression of nuclear receptor Rev-Erbα (Nr1d1) at 18:00, but had little influence on the nuclear receptor Rev-Erbβ (Nr1d2) and RORα. Conclusion. The Tibetan medicine Zuotai could influence the expression of clock genes, which could contribute to pharmacological and/or toxicological effects of Zuotai.

Laser-induced breakdown spectroscopy enhanced by a micro torch

A commercial butane micron troch was used to enhance plasma optical emissions in laser-induced breakdown spectroscopy (LIBS). Fast imaging and spectroscopic analyses were used to observe plasma evolution in the atmospheric pressure for LIBS without and with using a micro torch. Optical emission intensities and signal-to-noise ratios (SNRs) as functions of delay time were studied. Enhanced optical emission and SNRs were obtained by using a micro torch. The effects of laser pulse energy on the emission intensities and SNRs were studied. The same spectral intensity could be obtained using micro torch with much lower laser pulse energy. The investigation of SNR evolution with delay time at different laser pulse energies showed that the SNR enhancement factor is higher for plasmas generated by lower laser pulse energies than those generated by higher laser energies. The calibration curves of emission line intensities with elemental concentrations showed that detection sensitivities of Mn I 404.136 nm and V I 437.923 nm were improved by around 3 times. The limits of detection for both Mn I 404.136 nm and V I 437.923 nm are reduced from 425 and 42 ppm to 139 and 20 ppm, respectively, after using the micro torch. The LIBS system with micro torch was demonstrated to be cost-effective, compact, and capable of sensitivity improvement, especially for LIBS system operating with low laser pulse energy.

Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression

Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al₂O₃, and SiO₂. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al₂O₃, and SiO₂ in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al₂O₃, and SiO₂ using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

In situ imaging and control of layer-by-layer femtosecond laser thinning of graphene

Although existing methods (chemical vapor deposition, mechanical exfoliation, etc.) are available to produce graphene, the lack of thickness control limits further graphene applications. In this study, we demonstrate an approach to precisely thin graphene films to a specific thickness using femtosecond (fs) laser raster scanning. By using appropriate laser fluence and scanning times, graphene thinning with an atomic layer precision, namely layer-by-layer graphene removal, has been realized. The fs laser used was configured in a four-wave mixing (FWM) system which can be used to distinguish graphene layer thickness and count the number of layers using the linear relationship between the FWM signal intensity and the graphene thickness. Furthermore, FWM imaging has been successfully applied to achieve in situ, real-time monitoring of the fs laser graphene thinning process. This method can not only realize the large-scale thinning of graphene with atomic layer precision, but also provide in situ, rapid imaging capability of graphene for an accurate assessment of the number of layers.

Icariin is a PPARα activator inducing lipid metabolic gene expression in mice

Icariin is effective in the treatment of hyperlipidemia. To understand the effect of icariin on lipid metabolism, effects of icariin on PPARα and its target genes were investigated. Mice were treated orally with icariin at doses of 0, 100, 200, and 400 mg/kg, or clofibrate (500 mg/kg) for five days. Liver total RNA was isolated and the expressions of PPARα and lipid metabolism genes were examined. PPARα and its marker genes Cyp4a10 and Cyp4a14 were induced 2-4 fold by icariin, and 4-8 fold by clofibrate. The fatty acid (FA) binding and co-activator proteins Fabp1, Fabp4 and Acsl1 were increased 2-fold. The mRNAs of mitochondrial FA β-oxidation enzymes (Cpt1a, Acat1, Acad1 and Hmgcs2) were increased 2-3 fold. The mRNAs of proximal β-oxidation enzymes (Acox1, Ech1, and Ehhadh) were also increased by icariin and clofibrate. The expression of mRNAs for sterol regulatory element-binding factor-1 (Srebf1) and FA synthetase (Fasn) were unaltered by icariin. The lipid lysis genes Lipe and Pnpla2 were increased by icariin and clofibrate. These results indicate that icariin is a novel PPARα agonist, activates lipid metabolism gene expressions in liver, which could be a basis for its lipid-lowering effects and its beneficial effects against diabetes.

Age- and sex-related differences of organic anion-transporting polypeptide gene expression in livers of rats

Organic anion-transporting polypeptides (Oatps) play important roles in transporting endogenous substances and xenobiotics into the liver and are implicated in drug-drug interactions. Many factors could influence their expression and result in alterations in drug disposition, efficacy and toxicity. This study was aimed to examine the development-, aging-, and sex-dependent Oatps expression in livers of rats. The livers from SD rats during development (-2, 1, 7, 14, 21, 28, 35, and 60 d) and aging (60, 180, 540 and/or 800 d) were collected and total RNAs were extracted, purified, and subjected to real-time PCR analysis. Total proteins were extracted for western-blot analysis. Results showed that Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 were all hardly detectable in fetal rat livers, low at birth, rapidly increased after weaning (21 d), and reached the peak at 60 d. The Oatps remained stable during the age between 60-180 d, and decreased at elderly (540 and/or 800 d). After birth, Oatp1a1, Oatp1a4, and Oatp1b2 were all highly expressed in liver, in contrast, Oatp1a5 expression was low. Oatp expressions are male-predominant in rat livers. In the livers of aged rats, the Oatp expression decreased and shared a consistent ontogeny pattern at the mRNA and protein level. In conclusion, this study showed that in rat liver, Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 gene expressions are influenced by age and gender, which could provide a basis of individual variation in drug transport, metabolism and toxicity in children, elderly and women.

Potency of individual bile acids to regulate bile acid synthesis and transport genes in primary human hepatocyte cultures

Bile acids (BAs) are known to regulate their own homeostasis, but the potency of individual bile acids is not known. This study examined the effects of cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA) and ursodeoxycholic acid (UDCA) on expression of BA synthesis and transport genes in human primary hepatocyte cultures. Hepatocytes were treated with the individual BAs at 10, 30, and 100μM for 48 h, and RNA was extracted for real-time PCR analysis. For the classic pathway of BA synthesis, BAs except for UDCA markedly suppressed CYP7A1 (70-95%), the rate-limiting enzyme of bile acid synthesis, but only moderately (35%) down-regulated CYP8B1 at a high concentration of 100μM. BAs had minimal effects on mRNA of two enzymes of the alternative pathway of BA synthesis, namely CYP27A1 and CYP7B1. BAs increased the two major target genes of the farnesoid X receptor (FXR), namely the small heterodimer partner (SHP) by fourfold, and markedly induced fibroblast growth factor 19 (FGF19) over 100-fold. The BA uptake transporter Na(+)-taurocholate co-transporting polypeptide was unaffected, whereas the efflux transporter bile salt export pump was increased 15-fold and OSTα/β were increased 10-100-fold by BAs. The expression of the organic anion transporting polypeptide 1B3 (OATP1B3; sixfold), ATP-binding cassette (ABC) transporter G5 (ABCG5; sixfold), multidrug associated protein-2 (MRP2; twofold), and MRP3 (threefold) were also increased, albeit to lesser degrees. In general, CDCA was the most potent and effective BA in regulating these genes important for BA homeostasis, whereas DCA and CA were intermediate, LCA the least, and UDCA ineffective.

Expression of P450 and nuclear receptors in normal and end-stage Chinese livers

AIM: To investigate the expression of P450 enzyme genes by using end-stage liver disease samples and trimmed normal Chinese donor livers.

METHODS: The end-stage liver disease samples [n = 93, including hepatocellular carcinoma (HCC), peri-HCC tissue, hepatitis B virus cirrhosis, alcoholic cirrhosis, and severe cirrhosis] and trimmed normal Chinese donor livers (n = 35) from The Institute of Organ Transplantation in Beijing, China. Total RNA was extracted, purified, and subjected to real-time RT-PCR analysis.

RESULTS: For cytochrome P450 enzymes 1 (CYP1) family, the expression of CYP1A2 was decreased 90% in HCC, 80% in alcoholic cirrhosis, and 65% in severe cirrhosis. For CYP2 family, the expression of CAR was decreased 50% in HCC, but increased 50% in peri-HCC tissues. Similar decreases (about 50%) of CYP2B6, CYP2C9, CYP2C19, CYP2D6 and CYP2E1 were observed in HCC, as compared to peri-HCC tissues and normal livers. CYP2C19 were decreased in all end-stage liver diseases and CYP2E1 also decreased in alcoholic cirrhosis and severe cirrhosis. For CYP3 family, the expression of PXR was decreased 60% in HCC, together with decreases in CYP3A4, CYP3A5, and CYP3A7. In contrast, the expression of CYP3A7 was slightly increased in HBV cirrhosis. The expression of CYP4A11 was decreased 85% in HCC, 7% in alcoholic cirrhosis and severe liver cirrhosis, along with decreases in PPARα. The 93 end-stage livers had much higher inter-individual variations in gene expression than 35 normal livers.

CONCLUSION: The expression of CYP enzyme genes and corresponding nuclear receptors was generally decreased in end-stage liver diseases, and significant differences in gene expression were evident between peri-HCC and HCC.

BTG1 expression in thyroid carcinoma: diagnostic indicator and prognostic marker

We determined the expression and function of B cell translocation gene 1 (BTG1) in thyroid carcinoma. Thyroid samples were obtained from cancer lesions (n=83) and adjacent normal tissue (n=35) in thyroid cancer patients immediately after endoscopic biopsy. BTG1 expression was determined by immunohistochemistry and western blotting. The effect of BTG1 overexpression was examined in vitro utilizing the human thyroid cancer cell line FTC-133, stably transfected with a recombinant lentivirus (LeBTG1 cells) and compared to empty vector transfected controls (LeEmpty). BTG1 overexpression was verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting. The expression of proteins involved in cell cycle regulation (cyclin D1), apoptosis (Bcl-2) and cell migration (MMP-9) in LeBTG1 cells was analyzed by western blotting. The effect of BTG1 overexpression on cell viability and proliferation was assessed by MTT assay in LeBTG1 and LeEmpty cells. Flow cytometric analyses were used to evaluate the effect of BTG1 expression on cell cycle distribution and apoptosis. The migration and invasion potential of LeBTG1 cells was examined by plating cells in Matrigel-coated chambers. BTG1 protein expression was significantly lower in thyroid cancer tissue biopsies compared to normal tissue as measured by immunohistochemistry (36.1 vs. 80.0% of tissues; P<0.05) and western blotting (0.251±0.021 vs. 0.651±0.065; P<0.05). Decreased expression of BTG1 was significantly correlated with thyroid cancer lymph node metastasis, clinical stage and pathological differentiation (P<0.05), as well as with reduced overall 10‑year survival rates compared to patients with higher expression levels (30.2 vs. 66.7%; P<0.05). In vitro analyses revealed that LeBTG1 cells had a reduced survival fraction compared to control LeEmpty cells, with higher rates of apoptosis (11.6±2.1 vs. 2.1±0.4%; P<0.05). The proportion of LeBTG1 cells in G0/G1 stage and S phase was also significantly different from LeEmpty cells (81.8±6.3 and 10.2±1.0%, vs. 62.4±4.9 and 25.5±2.6%, respectively; P<0.05), and the migration and invasion of LeBTG1 cells was significantly impaired with respect to LeEmpty cells (72.0±8.0 and 55.0±7.0 vs. 113.0±16.0 and 89.0±9.0, respectively; P<0.05). These effects were accompanied by decreased protein expression of cyclin D1, Bcl-2 and MMP-9 in LeBTG1 cells (0.234±0.018, 0.209±0.021, 0.155±0.017, respectively) compared to control LeEmpty cells (0.551±0.065, 0.452±0.043, 0.609±0.072, respectively; P<0.05). Reduced BTG1 expression is associated with increased disease severity, suggesting it is a negative regulator of thyroid cancer and can serve as a prognostic indicator.

Accuracy improvement of quantitative analysis in laser-induced breakdown spectroscopy using modified wavelet transform

A modified algorithm of background removal based on wavelet transform was developed for spectrum correction in laser-induced breakdown spectroscopy (LIBS). The optimal type of wavelet function, decomposition level and scaling factor γ were determined by the root-mean-square error of calibration (RMSEC) of the univariate regression model of the analysis element, which is considered as the optimization criteria. After background removal by this modified algorithm with RMSEC, the root-mean-square error of cross-validation (RMSECV) and the average relative error (ARE) criteria, the accuracy of quantitative analysis on chromium (Cr), vanadium (V), cuprum (Cu), and manganese (Mn) in the low alloy steel was all improved significantly. The results demonstrated that the algorithm developed is an effective pretreatment method in LIBS to significantly improve the accuracy in the quantitative analysis.