[Health risk assessment of exogenous harmful pollutants in Chinese medicine: a review]

In recent years, the quality and safety problems have been limiting the internationalization of Chinese medicine. The pollutants in Chinese medicine, particularly the exogenous harmful pollutants mainly including mycotoxins, pesticide residues, heavy metals, harmful elements, and sulfur dioxide, are of high risks for people. Therefore, the World Health Organization(WHO) and relevant national organizations have clearly defined the maximum residue limits(MRLs) of such pollutants. Chinese Pharmacopoeia(2020 edition, volume Ⅳ) also demonstrates the detection methods, MRLs and preliminary risk assessment methods for four typical exogenous harmful pollutants in Chinese medicine. Therefore, continuous optimization of the health risk assessment system can further help further raise the quality and safety of Chinese medicine. This paper reviews the research on the health risk assessment of four typical exogenous harmful pollutants in Chinese medicine and discusses the problems of and challenges for the assessment system, which is expected to lay a scientific basis for the establishment of the risk warning mode and response measures suitable for specific types of Chinese medicine.

Wedelolactone-Loaded Micelles Ameliorate Doxorubicin-Induced Oxidative Injury in Podocytes by Improving Permeability and Bioavailability

Wedelolactone (WED) is commonly used for the treatment of doxorubicin (DOX)-induced kidney damage, but its efficacy is limited by its poor solubility and bioavailability. In this study, we developed a novel delivery system of WED-loaded micelles (WED-M) with Solutol^® HS15 and lecithin at an optimized ratio of 7:3 to improve the poor permeability and bioavailability of WED and to enhance its efficacy. The spherically shaped WED-M (particle size: 160.5 ± 3.4 nm; zeta potential: −30.1 ± 0.9 mV; entrapment efficiency: 94.41 ± 1.64%; drug loading: 8.58 ± 0.25%; solubility: 1.89 ± 0.06 mg/ml) has continuous stability over 14 days and a sustained release profile. The permeability of WED-M in Caco-2 cells indicated a significant 1.61-fold higher Papp AP to BL ratio than WED alone. Additionally, pharmacokinetic evaluation of WED-M demonstrated that the bioavailability of WED was increased 2.78-fold. Both HE staining and transmission electron microscopy showed an obvious improvement of pathological damage in WED-M treatment. Moreover, WED-M significantly enhanced the ROS level in mice and MPC5 podocytes. We concluded that using this micelle delivery system for WED could improve its permeability and bioavailability to attenuate DOX-induced oxidative injury in podocytes. This study provided important information on the fact that the micelle delivery system, WED-M, showed a significant improvement of renal damage.

[Effects of Arsenic Trioxide on Cdc20 and Mad2 in Acute Myeloid Leukemia HL-60 Cell Line]

OBJECTIVE

To investigate the effects of arsenic trioxide (As₂O₃) on Cdc20 and Mad2 in process of AML HL-60 cell proliferation.

METHODS

The proliferation of HL-60 cells was detected by CCK-8 method at different concentrations of arsenic trioxide for 24, 48 and 72 hours. The cell morphological changes were observed by inverted microscopy. The expressions of Mad2 and Cdc20 mRNA and protein in HL-60 cells treated with As₂O₃ for 48 h were detected by real-time PCR and Western blot respectively.

RESULTS

Arsenic trioxide significantly inhibited the HL-60 cell proliferation and displayed a good time-dose correlation. RT-PCR and Western blot showed that the expression of Mad2 was up-regulated and the expression of Cdc20 was down-regulated in HL-60 cells treated with arsenic trioxide of different concentration (4,8,10 µmol/L).

CONCLUSION

Arsenic trioxide can inhibit the human acute myeloid leukemia HL-60 cell proliferation, and its mechanism may be related with up-regulation of Mad2 expression and down-regulation of Cdc20 expression.

[Simultaneous determination of 8 main compounds in Eclipta Herba by UPLC]

To establish an UPLC method for the simultaneous determination of 8 compounds in Eclipta Herba, such as isoquercitrin, luteoloside, demethylwedelolactone, isochlorogenic acid A, isochlorogenic acid C, luteolin, wedelolactone and apigenin. The experiment was performed with a Waters Acquity UPLC BEH C₁₈ (2.1 mm×100 mm, 1.7 μm) column by gradient elution of 0.1% formic acid in water and acetonitrile: 0-4 min,10%-13% A; 4-10 min, 13%-16% A; 10-13 min, 16%-25% A; 13-17 min, 25%-28% A; 17-20 min,28%-40% A;20-25 min,40%-95% A. The flow rate was 0.3 mL•min⁻¹.. The condition of was the colum temperature was maintained at 35 ℃ and the detected wavelength was set at 350 mm. 8 components were separated clearly by this method. Also a good linearity was obtained between the chosen concentration(r≥0.999 0). The measured data showed that the recovery rate range from 96.60%-103.4% (n=6) and their RSD values were 0.86%-2.4%. The method has high recovery rate, good reproducibility and stability. It provides a scientific basis for the identification and quality evaluation of Eclipta Herba.

[Comparison of protective effects of eight ethyl acetate extracts from Eclipta prostrate on NHBE cells based on component structure theory]

To analyze and compare the protective effects of active components in different ethyl acetate extracts (EAEEPs) from Eclipta prostrate, in order to study the comparison of materials bases protecting normal human bronchial epithelial (NHBE) cells. The MTT assay was taken to compare the protective effect of different EAEEPs on cigarette smoke extracts (CSE) -induced NHBE cells. The ultra-performance liquid chromatography (UPLC) was applied to analyze the content of phenolic acid, coumaric grass ether and flavonoid in EAEEPs. According to the results, all of the eight EAEEPs (0-200 mg x L(-1)) showed certain protective effect on NHBE cells, with statistical difference. Specifically, the total mass of EAEEP VII (89.15 mg x L(-1)) and EAEEP VIII (57.44 mg x L(-1)), which showed the strongest activity, was not the highest, while EAEEP III (132.25 mg x L(-1)) displayed the highest total mass. In the combination with the "component structure" theory, the analysis showed a significant difference in the mass structure among phenolic acid, coumaric grass ether and flavonoid in EAEEP VIII and EAEEP VIII, which were 1.0: 1. 0: 0.5 and 1.0: 1.9: 0.8, respectively. The results suggested a specific optimal "component structure" relationship may exist in EAEEP, which could provide reference for the material base study and quality control.

Multielemental composition of suet oil based on quantification by ultrawave/ICP-MS coupled with chemometric analysis

Suet oil (SO) has been used commonly for food and medicine preparation. The determination of its elemental composition has became an important challenge for human safety and health owing to its possible contents of heavy metals or other elements. In this study, ultrawave single reaction chamber microwave digestion (Ultrawave) and inductively coupled plasma-mass spectrometry (ICP-MS) analysis was performed to determine 14 elements (Pb, As, Hg, Cd, Fe, Cu, Mn, Ti, Ni, V, Sr, Na, Ka and Ca) in SO samples. Furthermore, the multielemental content of 18 SO samples, which represented three different sources in China: Qinghai, Anhui and Jiangsu, were evaluated and compared. The optimal ultrawave digestion conditions, namely, the optimal time (35 min), temperature (210 °C) and pressure (90 bar), were screened by Box-Behnken design (BBD). Eighteen samples were successfully classified into three groups by principal component analysis (PCA) according to the contents of 14 elements. The results showed that all SO samples were rich in elements, but with significant differences corresponding to different origins. The outliers and majority of SO could be discriminated by PCA according to the multielemental content profile. The results highlighted that the element distribution was associated with the origins of SO samples. The proposed ultrawave digestion system was quite efficient and convenient, which could be mainly attributed to its high pressure and special high-throughput for the sample digestion procedure. Our established method could be useful for the quality control and standardization of elements in SO samples and products.

[Research thoughts and technology system framework of jinfukang oral liquid secondary exploitation]

Most Chinese medicine has good clinical efficacy and application. However, the material basis is vague for the lack of basic research, the value of Chinese medicine is hard to reflect for the low technology level and product quality is difficult to maintain for the quality control indicator selection is incorrect. Chinese medicine Jinfukang oral liquid is a typical product of Chinese medicines. Jinfukang oral liquid was selected as a model drug in this article. Based on the overall concept and systems theory of traditional Chinese medicine, the research idea and technology system for modern Chinese medicine secondary exploitation was formed. The system includes three parts, for the first, basic research to make clear the components structure and their action mechanism, for the second, technology upgraded to optimize process and improve the product quality, for the last, exploring the associated industry to form the industrial chain. The research ideas and technology system based on the material basis research and development of modern Chinese medicine, guided with component structure in Chinese medicine and aimed clinical needs. This research ideas and technology system provides strategies and methods for the development of modern Chinese medicine secondary exploitation.

In vitro study on cytotoxicity and intracellular formaldehyde concentration changes after exposure to formaldehyde and its derivatives

HeLa cells were exposed to formaldehyde and its metabolic derivatives, methanol, formic acid, and acetaldehyde, to investigate that the toxicity of formaldehyde is not caused by the chemical group. After 1 h of treatment with formaldehyde, mitochondrial assays showed that low concentrations (e.g. 10 μmol/L) of formaldehyde promoted growth of the HeLa cells, while higher concentrations (e.g. ≥62.5 μmol/L) inhibited cell growth; while all four chemicals at a concentration of 125 μmol/L affected cell growth, formaldehyde affected the largest. Reactive oxygen species concentration increased with the concentration of the exposure chemical. The endogenous formaldehyde content increased the most in the formaldehyde group, but in other three groups, it did not increase as the exposure concentration increased. Expression of dehydrogenase (formaldehyde dehydrogenase (FDH)) in the formaldehyde (10.40) and methanol (10.60) groups increased significantly compared with the control (1), while it was similar to the control in formic acid (0.90) and acetaldehyde (1.10) groups. Our results suggest that formaldehyde could affect cell activity and even enter cells. Exposure to formaldehyde changes the endogenous formaldehyde concentration in cells within 24 h, and this induces expression of FDH for formaldehyde degradation to maintain the formaldehyde balance. The toxicity of formaldehyde is not caused by the carbon atoms in the aldehyde, hydroxyl, or carboxyl groups. Formaldehyde is hypothesized to be an important signaling molecule in the regulation of cell growth and maintenance of the endogenous formaldehyde level.

Protection of glycyrrhizic acid against AGEs-induced endothelial dysfunction through inhibiting RAGE/NF-κB pathway activation in human umbilical vein endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice (Glycyrrhiza uralensis roots) is used as a traditional medicine for the treatment of diabetes mellitus and its vascular complications. Glycyrrhizic acid (GA, also known as Glycyrrhizin), a triterpenoid saponin glycoside, is considered to be a bioactive component in Licorice and is beneficial to diabetic vascular complications.

AIM OF STUDY

The present study was conducted to evaluate the potential protective activities on AGEs-induced endothelial dysfunction, including anti-apoptosis, antioxidant stress and anti-proinflammatory responses, and explore the underlying mechanism.

MATERIALS AND METHODS

Human umbilical vein endothelial cells (HUVECs) were incubated and pre-treated with GA (10(-9)-10(-6)M) or RAGE-Ab (5μg/ml) in the presence or absence of 200μg/ml AGEs. AO/EB fluorescence staining assay was performed to evaluate anti-apoptosis activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in cell supernatant were detected by kits while the intracellular reactive oxygen species (ROS) generation was determined by 2,7-dichlorodihydrofluorescin diacetate (DCFH-DA) kit. Immunocytochemistry analysis was designed to determine transforming growth factor beta1(TGF-β1) protein expression while immunofluorescence analysis for RAGE and NF-kB. The protein expressions of TGF-β1, RAGE and NF-kB were analyzed by Western blot analysis.

RESULTS

Pretreatment with GA at a concentration of 10(-8)-10(-6)M significantly reduced the AGEs-induced apoptosis in HUVECs. GA significantly increased antioxidant enzyme SOD activity and decreased peroxide degradation product MDA level in a dose-dependent manner. Furthermore, GA also remarkably inhibited the overgeneration of AGEs-induced ROS. Both immunocytochemistry analysis and western blot analysis showed that GA significantly decreased the protein expression of poinflammatory cytokine TGF-β1 in a similar manner which RAGE-Ab did. Additionally, AGEs-induced RAGE and NF-kB protein expressions were down-regulated significantly by the pretreatment with GA or RAGE-Ab.

CONCLUSION

These findings provide evidences that GA possesses protective activity on AGEs-induced endothelial dysfunction, including anti-apoptosis, anti-inflammation and antioxidant stress, via inhibiting RAGE/NF-kB pathway. GA might be an alternative for the prevention and treatment of diabetic vascular complications in an appropriate dosage.

[Chemical constituents of Nauclea officinalis]

In order to study the chemical constituents in the water extract of the stem of Nauclea officinalis, column chromatography over D101 macroporous resin and silica gel and an automatic purification system were used to isolate and purify the chemical constituents from the extract. Nine compounds were obtained. By analysis of the physicochemical properties and spectral data, their structures were identified as naucleamide G (1), 3, 4-dimethoxyphenol-beta-D-apiofuranosyl (1-->6)-beta-D-glucopyranoside (2), kelampayoside A (3), 3alpha, 5alpha-tetrahydrodeoxycordifoline lactam (4), naucleamide A-10-O-beta-D-glucopyranoside (5), pumiloside (6), 3-epi-pumiloside (7), strictosamide (8) and vincosamide (9), separately. Among them, compound 1 is a new compound, compound 2 was found in plants of the genus Nauclea for the first time, and compounds 3 and 4 were isolated from this plant for the first time.

Acid volatile sulfides and simultaneously extracted metals in a metal-polluted area of Taihu Lake, China

There were similar distribution characteristics for acid volatile sulfides (AVS) and simultaneously extracted metals (SEM) in surface sediments, and the concentrations of AVS and SEM decreased from the deposition area to the center of the bay (lake). The ratio of AVS to SEM was <1 in the surface sediments, indicating that heavy metals in surface sediments may be bioavailable. The concentration of AVS increased with sediment depth, followed by a decrease with large variation, while the concentration of SEM remained constant. By comparing the concentration of SEM with total metals, it was shown that extracted Cu and Ni decreased with sediment depth, indicating increasing association of Cu and Ni with sulfides in deeper sediment layers. The lower extracted ratios for Pb and Zn compared with sulfidic sediment illustrated that AVS should not have strong control on sediment Pb and Zn. The molar ratio of AVS and reactive iron showed that heavy metals were dynamic and active in sediments in this lake.

Effects of exogenous organic chelators on phytochelatins production and its relationship with cadmium toxicity in wheat (Triticum aestivum L.) under cadmium stress

Phytochelatins (PCs) have been proposed as a potential biomarker for metal toxicity. In this study, cadmium (Cd) toxicity, PCs production and their relationship in wheat under Cd stress were examined using various exogenous organic chelator-buffered nutrient solutions. Single Cd stress produced strong toxic effects, as indicated by decreases of growth parameters, high level of lipid peroxidation in leaf and overproduction of PCs in root. Exogenous organic chelators with proper dose more or less reduced Cd toxicity by increasing growth parameters and decreasing lipid peroxidation in leaves. Of organic chelators (EDTA, DTPA, citric acid, malic acid and oxalic acid), EDTA was the most effective in decreasing Cd toxicity in plants, followed by DTPA and citric acid. Simultaneously, the concentrations of Cd-induced PCs in roots decreased, and the greatest decrease was caused by application of EDTA and DTPA. Linearly positive relationships were observed between Cd toxicity and root PCs concentrations under the influences of organic chelators, particularly EDTA, DTPA and citric acid. Furthermore, present results provide stronger evidence that PCs synthesis in plant cells was related to free Cd ion concentrations, not total Cd, and demonstrate that the levels of PCs production in plants correlated well with toxic effects caused by the bioavailable Cd levels.

Effects of interactions between cadmium and zinc on phytochelatin and glutathione production in wheat (Triticum aestivum L.)

It has been proposed that phytochelatins (PCs) act as a biomarker for the evaluation of metal toxicity. Little attention has been paid to the effects on metal combinations and glutathione (GSH), the most abundant cellular thiol. In the present study the effects of interactions between cadmium (Cd) and zinc (Zn) on PC and GSH production were examined in wheat tissue over 14 days' exposure. The results showed that the presence of Zn alleviated Cd toxicity, accompanied by a reduction of Cd uptake. Cd and Zn exposure increased PC-SH levels in concentration-, tissue- and time-dependent manners. Of the two metals, Cd was more effective than Zn in PC-SH production. Interactions of Cd and Zn with respect to PC-SH production may be synergistic or inhibitory, strongly depending on duration of exposure and concentration of the metal combinations. Cd also stimulated GSH production in concentration-, tissue- and time-dependent manners, whereas Zn had no significant effects on GSH levels. Compared to the presence of Cd alone, the presence of Zn reduced GSH levels in a tissue-dependent manner over the growth period. The results of the study suggest that metal interactions should be highly considered in the application of PCs and GSH as potential biomarkers for the evaluation of metal toxicity, as most metal-polluted natural environments are contaminated with more than one metal.