Paederosidic acid protect bone mass in lipopolysaccharide-treated rats by reducing oxidative stress and inflammatory.

Paederosidic acid (PA) has shown beneficial effects in anti-inflammatory studies, but it is unclear whether PA has positive impacts on bone loss induced by lipopolysaccharide (LPS). This study aims to investigate the influence of PA on bone loss in LPS-treated rats. The study assesses changes in the viability and osteogenic potential of MC3T3-E1 cells, as well as osteoclast differentiation in RAW264.7 cells in the presence of LPS using CCK-8, ALP staining, AR staining, and Tartrate-resistant acid phosphatase (TRAP) staining. In vitro experiments indicate that LPS-induced inhibition of osteoclasts (OC) and Superoxide Dismutase 2 (SOD2) correlates with heightened levels of inflammation and oxidative stress. Furthermore, PA has demonstrated the ability to alleviate oxidative stress and inflammation, enhance osteogenic differentiation, and suppress osteoclast differentiation. Animal experiments also show that PA significantly upregulates SOD2 expression while downregulating TNF-α expression (all, p < 0.05), leading to the restoration of impaired bone metabolism, improved bone strength, and increased bone mineral density (all, p < 0.05), compared to the control group. The collective experimental findings strongly suggest that PA can enhance osteogenic activity in the presence of LPS by reducing inflammation and oxidative stress, hindering osteoclast differentiation; hence mitigating bone loss in LPS-treated rat models.

Structure-based virtual screening for discovery of paederosidic acid from Paederia scandens as novel P2Y14R antagonist.

BACKGROUND: The activation of P2Y14 receptor (P2Y14R) promotes osteoclast formation and causes neuropathic pain, exhibiting possible link to osteoarthritis (OA). Given lack of P2Y14R antagonist, the present study aims to search a novel P2Y14R antagonist with low toxicity and high activity from natural products as a possible drug candidate in treatment of OA. METHODS: The role of P2Y14R on OA was verified using P2Y14R knockout (KO) rats. Molecular docking virtual screening strategy and activity test in P2Y14R stably-expressed HEK293 cells were used to screen target compound from natural product library. The MM/GBSA free energy calculation/decomposition technique was used to determine the principal interaction mechanism. Next, the binding of target compound to P2Y14R was examined using cellular thermal shift assay and drug affinity responsive target stability test. Finally, the therapeutic effect of target compound was performed in monosodium iodoacetate (MIA)-induced OA mouse model. To verify whether the effect of target compound was attributed to P2Y14R, we establish the osteoarthritis model in P2Y14R KO mice to perform pharmacodynamic evaluation. Importantly, to investigate the potential mechanism by which target compound attenuate OA, expressions of the major transcription factors involved in osteoclast differentiation were detected by western blot, while markers of nerve damage in dorsal root ganglion (DRG) were evaluated by RT-qPCR and immunofluorescence techniques. RESULTS: Deficiency of P2Y14R alleviated pain behavior and cartilage destruction in MIA-induced OA rats. 14 natural compounds were screened by Glide docking-based virtual screening, among which paederosidic acid exhibited the highest antagonistic activity to P2Y14R with IC50 of 8.287 µM. As a bioactive component extracted from Paederia scandens, paederosidic acid directly interacted with P2Y14R to enhance the thermostability and decrease the protease sensitivity of target protein, which significantly inhibited receptor activator for nuclear factor-κB ligand (RANKL)-mediated osteoclastogenesis. More importantly, paederosidic acid suppressed osteoclast formation by downregulating expressions of NFAT2 and ATP6V0D2, as well as relieved neuropathic pain by decreasing expressions of CGRP, CSF1 and galanin in DRG. CONCLUSIONS: Paederosidic acid targeted P2Y14R to improve OA through alleviating osteoclast formation and neuropathic pain, which provided an available strategy for developing novel drug leads for treatment of OA.

Antitumor activity of paederosidic acid in human non-small cell lung cancer cells via inducing mitochondria-mediated apoptosis.

This study was aimed to investigate antitumor activity of paederosidic acid (PA) in human non-small cell lung cancer cells and explore the related mechanisms. The anti-proliferative effects of PA on A549 cells were evaluated by MTT method and the IC50 values were calculated. Furthermore, the PA-induced apoptosis in A549 cells was determined by fluorescence microscope via staining with DAPI and by flow cytometer via staining with FITC conjugated Annexin V/PI. The expression of apoptosis-related or signaling proteins was investigated by Western blotting. Our results demonstrated that PA showed significant anti-tumor activity on lung cancer in vitro; the mechanisms were involved in inducing mitochondria-mediated apoptosis via up-regulation of caspase-3, caspase-8, caspase-9, Bid, Bax, down-regulation of Bcl-2 and stimulating the release of Cyto-C from mitochondria. In addition, JNK phosphorylation levels significantly increased concomitantly with decrease in Akt phosphorylation after treatment with PA in A549 cells. However, JNK siRNA-transfected cells diminished PA-induced caspase-3, 8 and 9, Bid and Bax activaton while enhanced the Bcl-2 activation. Collectively, these results indicated that PA-induced JNK activation played an important functional role in apoptosis.

Anticonvulsant and sedative effects of paederosidic acid isolated from Paederia scandens (Lour.) Merrill. in mice and rats.

This study was designed to evaluate the anticonvulsant and sedative effects of paederosidic acid isolated from Paederia scandens (Lour.) Merrill. in mice and rats. In the present study, anticonvulsant activities of paederosidic acid were evaluated by maximal electroshock and pentylenetetrazole-induced seizures in male mice. Then, pentobarbital sodium-induced sleeping time and locomotor activity tests in mice were used to evaluate the sedative effects of paederosidic acid. Finally, the mechanism of paederosidic acid was explored by evaluating the contents of Glu and GABA in the brain, and Western blot was used to measure GAD65 expression in the mouse brain. Paederosidic acid (5, 10, 20, and 40 mg/kg, ip) had significant anticonvulsant and sedative effects. Moreover, paederosidic acid increased brain gamma-aminobutyric acid and decreased glutamic acid in the brain, and it up-regulated expressions of GAD 65. In conclusion, our results suggest that paederosidic acid may be a promising future therapeutic agent for treatment of epilepsy.