Asperuloside ameliorates lipopolysaccharide-induced primary human periodontal ligament cell injury by decreasing TLR4 expression and NF-κB activation

Comparative study of Scleromitrion diffusum and Oldenlandia corymbosa: Microscopy, TLC, HPLC, and antioxidant activity

Quality control of herbal medicines is crucial, especially the role of herbal drug identification. This is essential for preventing the misuse of herbs, which can affect efficacy or cause toxicity. Scleromitrion diffusum is a common herb, yet it is often mistaken for Oldenlandia corymbosa. This study analyzed the morphology, microscopy, thin-layer chromatography (TLC), and high-pressure liquid chromatography (HPLC) using two markers, asperuloside and scandoside methyl ester, to distinguish between S. diffusum and O. corymbosa with the analysis included 10 samples of S. diffusum and 10 samples of O. corymbosa collected from the Taiwan market. By quantifying the total polyphenols and flavonoids, we investigated the antioxidant activity, including the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging effect, 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+) scavenging effect, and reducing power to further elucidate the biological effects of the two herbs. The results of this study revealed notable differences in microscopy and suggested a TLC method for distinguishing between the two herbs in the market. In HPLC, the ratios of asperuloside and scandoside methyl ester differed between the two herbs. S. diffusum contained a higher asperuloside content. In contrast, O. corymbosa contained higher concentrations of scandoside methyl esters. With more total polyphenols and flavonoids in S. diffusum than those in O. corymbosa, the antioxidant activity of S. diffusum was superior to that of O. corymbosa. This study provides a comprehensive understanding for the identification and quality evaluation of S. diffusum in the market. RESEARCH HIGHLIGHTS: The study consolidates and clarifies the morphological and microscopic differences between Scleromitrion diffusum and Oldenlandia corymbosa - a common adulterant species of S. diffusum on the Taiwan markets. Using Asperuloside and Scandoside methyl ester as two chemical markers, the study proposes a TLC method for rapidly testing S. diffusum and O. corymbosa on the market. Through HPLC analysis, our results showed that S. diffusum and O. corymbosa had a clear difference in the ratio of two markers, Asperuloside and Scandoside methyl ester: Asperuloside/Scandoside methyl ester in S. diffusum is higher than that in O. corymbosa. Through phytochemicals contents, including total phenols content, flavonoids content, and antioxidant activity, including DPPH, ABTS•+ scavenging activity, and reducing power, S. diffusum showed slightly higher levels of phenols and flavonoids as well as a better antioxidant activity than O. corymbosa.

Increased expression of angiopoietin-like protein 4 regulates matrix metalloproteinase-13 expression in Porphyromonas gingivalis lipopolysaccharides-stimulated gingival fibroblasts and ligature-induced experimental periodontitis

BACKGROUND

Angiopoietin-like protein 4 (ANGPTL4) is produced in chronic or acute inflammation. Although ANGPTL4 increases in the periodontal ligament fibroblasts during hypoxia, the involvement and role of ANGPTL4 in periodontitis have not been elucidated.

OBJECTIVE

In this study, we investigated whether ligature-induced experimental periodontitis and/or Porphyromonas gingivalis lipopolysaccharides (Pg-LPS) would upregulate ANGPTL4 expression and whether ANGPTL4 would somehow involve in the expression of matrix metalloproteinases (MMPs) which are key molecules in the process of periodontal tissue destruction.

METHODS

Experimental periodontitis was induced in 6-week-old male Sprague-Dawley rats by placing a nylon suture around the neck of the maxillary second molar. Two weeks after the induction of periodontitis, the periodontal tissue was excised and analyzed by histological/immunohistochemical staining and gene expression analyses. Human gingival fibroblasts (hGFs) were stimulated with Pg-LPS. The gene expression of ANGPTLs and receptors involved in ANGPTL4 recognition were observed. We also confirmed the changes in gene expression of MMPs upon stimulation with human ANGPTL4. Furthermore, we downregulated ANGPTL4 expression by short interfering RNA in hGFs and investigated the effect of Pg-LPS on MMP production.

RESULTS

Induction of periodontitis significantly increased the expression of ANGPTL4 in the gingiva. Pg-LPS significantly increased the gene and protein expression of ANGPTL4 in hGFs but not the gene expression of other ANGPTLs or ANGPTL receptors. Recombinant human ANGPTL4 significantly increased MMP13 gene expression in hGFs. We also confirmed that MMP13 expression was increased in the gingiva during experimental periodontitis. Pg-LPS induced MMP13 gene expression in hGFs. These results suggest the pivotal role of ANGPTL4 in periodontitis.

CONCLUSION

Periodontitis increases ANGPTL4 expression in the gingiva, further suggesting that increased ANGPTL4 may be a factor involved in enhancing MMP13 expression.

Protective effects of asperuloside against cyclophosphamide-induced urotoxicity and hematotoxicity in rats

Cyclophosphamide (CP) is a highly efficacious chemotherapy drug for treating cancers and autoimmune disorders, but it is also notable for its deleterious side effects including urotoxicity in cancer patients, which has been extensively linked to CP-induced oxidative/inflammatory cascades. Herein, we investigated the protective effects of asperuloside (ASP) against CP-induced urotoxicity. Rats received oral administration of ASP (20 and 40 mg/kg bw/day) for 35 days and were injected with weekly CP (100 mg/kg bw, i.p.) for 4 weeks to induce acute bladder toxicity. CP acutely altered haematological parameters and significantly reduced body weight gain, bladder glutathione peroxidase, reduced glutathione, catalase, and superoxide dismutase activities. Furthermore, CP caused an upward surge in bladder malondialdehyde, nuclear factor-kappa B, tumour necrosis factor-α, interleukin-1β, and interleukin 6 concentrations. ASP supplementation ameliorated CP-induced haematological derangement and bladder urotoxicity through the restoration of oxidative and inflammatory parameters in CP-treated rats. These findings suggested that ASP could be valorised as a possible therapeutic agent against chemotherapy-related toxicities as well as oxidative damage disorders.

α-Cyperone Ameliorates Lipopolysaccharide-Induced Inflammation and Apoptosis of Periodontal Ligament Stem Cells via Blocking the Toll-Like Receptor 4/NF-κB Signaling

Periodontitis is a long-lasting inflammatory microbial sickness that could cause damage to the periodontal ligament, gums, cementum and alveolar bone directly. Cyperus rotundus is a common traditional Chinese medicine clinically with many pharmacological activities, α-Cyperone is a bioactive ingredient abundant in Cyperus rotundus, few studies have focused on its anti-fungal and anti-oxidative stress activities in mice, during this research, we firstly investigated the impact of α-Cyperone on PDLSCs inflammatory by LPS stimulation. Our findings illustrated that α-Cyperone exerted no influence on PDLSCs viability at concentrations lower than 60 μM, and the release of inflammatory cytokines decreased with an increase in LPS concentration. Meanwhile, we found that α-Cyperone effectively restrained LPS-induced PDLSC cell apoptosis by CCK-8 cell viability assay and TUNEL-positive staining. Furthermore, the TLR4 expression and NF-κB kinase activation were greatly repressed by α-Cyperone treatment in LPS-induced PDLSCs inflammatory model. Subsequently, enhanced TLR4 expression was observed to reverse the suppressed release of inflammatory cytokines and decreased apoptosis effects mediated by α-Cyperone in LPS-cotreated PDLSCs, indicating that the deactivation of TLR4 and downstream NF-κB were implicated in favoring α-Cyperone-triggered protective effects of LPS in PDLSCs.

Synthesis, activity and mechanism for double-ring conjugated enones

The relationship between TLR4 and inflammation-related diseases has been paid more and more attention. The studies have shown that TLR4/NF-κB signaling pathway plays an important role in the transmission of inflammatory signals. A large number of pro-inflammatory factors, chemokines, adhesion factors, TLR4 and its ligands interact with each other, and jointly promote the development of diseases. In this work, 8 target compounds were synthesized to screen the inhibitory activity of TLR4 in vitro. The results of TLR4 inhibition test in vitro showed that the double-ring conjugated enones had a good inhibitory activity, and the IC₅₀ value of compound 4f was 0.56 ± 0.10 μM, and it was superior to the positive control methotrexate. To further study the anti-inflammatory effect and mechanism of double-ring conjugated enones by using LPS induced rat synovial cell inflammation model. The results of the mechanism test showed that compound 4f could effectively promote the apoptosis of rat synovial cells, and the mechanism might be related to the up-regulation of the expression of apoptosis-related protein Caspase-3. In addition, compound 4f could significantly inhibit the increase of inflammatory factors TNF-α, IL-1β and IL-6 in rat synovial cells induced by LPS, showing a good anti-inflammatory activity. In the TLR4/NF-κB signaling pathway test of rat synovial cells, compound 4f can effectively regulate the expression levels of TLR4, MyD88, NF-κB and IκB related proteins in TLR4/NF-κB signaling pathway, which may be due to its inhibition of LPS-induced inflammation in rat synovial cells. At the same time, it inhibits the abnormal proliferation of cells and its important mechanism promoted of apoptosis.