Effects of polystyrene nanoplastics on lead toxicity in dandelion seedlings.

Increasing rates of commercialization and industrialization have led to the comprehensive evaluation of toxic effects of microplastics on crop plants. However, research on the impact of functionalized polystyrene nanoplastics on the toxicity of heavy metals remains limited. This study investigated the effects of polystyrene, carboxy-modified polystyrene, and amino-modified polystyrene on lead (Pb) toxicity in dandelion seedlings. The results showed that carboxy -modified polystyrene with a negative charge absorbed more Pb2+ than polystyrene and amino-modified polystyrene, and their maximum adsorption amounts were 5.328, 0.247, and 0.153 µg g-1, respectively. The hydroponic experiment demonstrated that single amino-modified polystyrene was more toxic to dandelion seedlings than polystyrene and carboxy-modified polystyrene. The presence of Pb2+ was found to increase antioxidant enzymes (superoxide dismutase and catalase) and non-antioxidant enzymes (glutathione and ascorbic acid) activities in response to excessive reactive oxygen species in dandelion leaves and roots treated with polystyrene and carboxy-modified polystyrene, while it did not change much when amino-modified polystyrene was added. Interestingly, compared with single Pb2+, the addition of amino-modified polystyrene with positive charges induced an obvious decrease in the above parameters; however, they declined slightly in the treatments with polystyrene and carboxy-modified polystyrene despite a stronger adsorption capacity for Pb2+. Similarly, the bioactive compounds, including flavonoids, polyphenols, and polysaccharides in dandelion, showed a scavenging effect on O2- and H2O2, thereby inhibiting the accumulation and reducing medicinal properties. This study found that the effects of microplastics on the uptake, distribution, and toxicity of heavy metals depended on the nanoparticle surface charge.

Experimental study on treatment of heavy metal-contaminated soil by manganese-oxidizing bacteria.

There are many studies on the treatment of heavy metals by manganese-oxidizing bacteria and the reaction is good; the problem of compound pollution of heavy metals in soil has been difficult to solve. In this study, the application of manganese-oxidizing bacteria in soil was studied. The tolerance of manganese-oxidizing strains (Pseudomonas taiwanensis) to environmental conditions and the treatment effect of heavy metals As, Pb, and Cd in aqueous solution were investigated, and the effect of iron-manganese ratio on the treatment effect was discussed. The results showed that the suitable pH conditions for the growth of P. taiwanensis were 5-9, and the salt tolerance was 6% (by sodium chloride). The tolerant concentrations for heavy metals As(V) and Mn(II) were 500 mg L-1 and 120 mg L-1, respectively. The strains were enriched by nutrient broth medium. After the logarithmic phase, the bacterial suspension was mixed with ATCC#279 medium at a ratio of 1:10, and a certain amount (10 mg L-1) of Mn(II) was added. The results of As, Pb, and Cd removal in the composite polluted water phase were 22.09%, 30.75%, and 35.33%, respectively. The molar ratio of manganese and iron affected the removal efficiency of single arsenic, the highest efficiency is 68%, and the ratio of iron to manganese is 1:5. However, when the soil was treated by the same method, the results showed that not all metals were passivated, such as Cu. At the same time, for As, Pb, and Cd, the treatment effects in soil were worse than those in water, perhaps more consideration should be given to environmental conditions, such as soil moisture and temperature, when manganese-oxidizing bacteria are used to treat soil.

Baicalin relieves lipopolysaccharide-evoked inflammatory injury through regulation of miR-21 in H9c2 cells.

Myocarditis is a common heart disease which lacks effective treatment till now. Baicalin possesses plenty of activities, including anti-inflammation. In this investigation, we attempted to investigate the influences of Baicalin on Lipopolysaccharide (LPS)-evoked H9c2 cells.Cells viability, apoptosis, and expressions of apoptosis-associated proteins were, respectively, measured utilizing CCK-8 assay, flow cytometry and western blot. The levels of IL-6 and TNF-α were detected through enzyme-linked immunosorbent assay, western blot and qRT-PCR. miR-21 expression was detected through qRT-PCR and was silenced using cell transfection. The expressions of NF-κB and PDCD4/JNK pathways related proteins were measured through western blot. We found that LPS stimulation induced cell apoptosis and upregulation of IL-6 and TNF-α. Baicalin treatment effectively suppressed LPS-induced inflammation and apoptosis. The NF-κB and PDCD4/JNK pathways were blocked by Baicalin. Additionally, the enhanced expression of miR-21 triggered by LPS was further elevated by Baicalin. Further study revealed that the inhibiting effects of Baicalin on LPS-evoked injury were largely attenuated by knockdown of miR-21. Moreover, the associated NF-κB and JNK pathways, which were suppressed by Baicalin treatment, were then activated by knockdown of miR-21. Our present study revealed that Baicalin alleviated LPS-evoked inflammatory injury via suppressing the NF-κB and PDCD4/JNK pathways through regulating miR-21 expression.

The triptolide-induced apoptosis of osteoclast precursor by degradation of cIAP2 and treatment of rheumatoid arthritis of TNF-transgenic mice.

This study aims to discuss the effect of triptolide (TPL) on rheumatoid arthritis (RA) and the mechanism related to osteoclast precursor (OCP) and osteoclast (OC). TNF-transgenic RA mice were treated with different doses of TPL by gavage. After the administration was finished, the curative effects were evaluated and compared, and the OCP apoptosis rates, the OC number, and the OC differentiation ability in vitro were detected. Finally, splenocytes of wild-type mice were cultured in vitro and induced to differentiate into OCP, and the cell apoptosis rate, cIAP2, and apoptotic effectors expression level were detected after cIAP2 overexpression and TPL administration. After TPL administration, the RA symptoms in the TPL groups were all better, the apoptosis rate of OCP was higher, and the amount of OC in vitro were lower than that in the control group (all P < 0.05), and all of the changes in the high-dose group were more obvious than the low-dose group. In splenocytes cells cultured in vitro, cIAP2 overexpression could decrease the apoptosis rate of OCPs and increase the OC number, and TPL treatment could down-regulate the cIAP2 and promote OCP apoptosis and OC reduction. In conclusion, TPL could induce OCP apoptosis and inhibit OC formation to effectively treat RA by mediating cIAP2 degradation.

In vitro and in vivo evaluation of capsaicin-loaded microemulsion for enhanced oral bioavailability.

BACKGROUND: Capsaicin, as a food additive, has attracted worldwide concern owing to its pungency and multiple pharmacological effects. However, poor water solubility and low bioavailability have limited its application. This study aims to develop a capsaicin-loaded microemulsion to enhance the oral bioavailability of the anti-neuropathic-pain component, capsaicin, which is poorly water soluble. RESULTS: In this study, the microemulsion consisting of Cremophor EL, ethanol, medium-chain triglycerides (oil phase) and water (external phase) was prepared and characterized (particle size, morphology, stability and encapsulation efficiency). The gastric mucosa irritation test of formulated capsaicin was performed in rats to evaluate its oral feasibility, followed by the pharmacokinetic study in vivo. Under these conditions, the encapsulated capsaicin revealed a faster capsaicin release in vitro coupled with a greater absorption in vivo when compared to the free capsaicin. The oral bioavailability of the formulated capsaicin-loaded microemulsions was 2.64-fold faster than that of free capsaicin. No significant irritation was observed on the mucosa from the pathological section of capsaicin-loaded microemulsion treated stomach. CONCLUSION: These results indicate that the developed microemulsion represents a safe and orally effective carrier for poorly soluble substances. The formulation could be used for clinical trials and expand the application of capsaicin.

Effect of Myrtol standardized on mucus hypersecretion and clearance of Pseudomonas aeruginosa in a rat model of chronic obstructive pulmonary disease.

This study aimed to investigate the effect of Myrtol standardized (GeloMyrtol forte) in the treatment of chronic obstructive pulmonary disease (COPD) in an animal model. A total of 93 experimental rats were randomly divided into 6 groups: control (n = 6), exposure to cigarette smoke (CS, n = 6), CS plus Myrtol standardized treatment (CS + M, n = 6), Pseudomonas aeruginosa (PA) infection (PA, n = 25), CS + PA (n = 25), and CS + PA + M (n = 25). For all 62 CS rats, they were exposed to cigarette smoke for a period of 12 weeks. During this time period the 31 CS + M rats (CS + M; CS + PA + M) received 300 mg/kg/day Myrtol standardized intragastrically always 30 min prior to smoke exposure. For CS + PA and CS + PA + M rats, intratracheal PA inoculation was performed after the 12 weeks of smoke exposure. All intratracheal PA inoculations were followed by a post-infection examination at 6, 12, 24, 48 and 72 h in each 5 rats. All study animals were euthanized and their lungs were excised; the left lung was homogenized for determination of bacterial load and measurements of TNF-alpha and IL-6, the right lungs were preserved for histo- and immunohistochemical examinations (e. g. MUC5AC). The lungs from CS rats were pathologically similar to those of COPD patients with the characteristics of goblet cell metaplasia and MUC5AC hypersecretion. CS animals had a significantly greater number of MUC5AC positive cells in the bronchial epithelial cells, and significantly increased expression levels of TNF-alpha and IL-6 after PA infection. However, the administration of Myrtol standardized significantly (p = 0.002) attenuated MUC5AC hypersecretion, measured as integrity optical density (IOD), in CS + M rats (45.98 +/- 6.25) as compared to CS alone (65.55 +/- 11.18) rats. The same applies at different time points between CS + PA rats (65.15 +/- 11.94, 75.88 +/- 7.42, 81.2 +/- 6.49, 75.14 +/- 6.85 and 67.32 +/- 10.61, respectively) and CS + PA + M rats (47.08 +/- 4.78, 54.22 +/- 6.59, 65.4 +/- 6.12, 59.98 +/- 4.96 and 48.43 +/- 7.29, respectively). Similar effects were found in the production of IL-6 and TNF-alpha in the CS + PA + M lungs. Similarly the bacterial load of 10,980 +/- 4,253 CFU in CS + PA + M was significantly lower compared to 42,400 +/- 3,296 CFU in CS + PA lungs after 72 h PA infection. In conclusion, this experimental study demonstrates a significant therapeutic effect of Myrtol standardized in treating common pathological conditions, such as airway mucus hypersecretion and defect of mucociliary functions in COPD.