Chemical constituents from the deep sea-derived Streptomyces xiamenensis MCCC 1A01570 and their effects on RXRα transcriptional regulation.

From the deep sea-derived Streptomyces xiamenensis MCCC 1A01570, eight cyclic dipeptides (1-8) and five phenolics (9-13) were obtained. Cyclo-(I-Pro-D-Leu) (4) could moderately promote the gene transcriptional function of nuclear receptor RXRα, while 2, 3, and 13 showed weak reduction in RXRα gene transcriptional activities induced by 9-cis-retinoid acid (RA). These compounds might have beneficial effects against intractable diseases with relation to RXRα, such as cancer and metabolic diseases, due to their potential activities on regulating the transcriptional activation function of RXRα. In addition, 1-6, 8, 10, and 12 (20 µM) showed mild in vitro cytotoxicity against three cancer cell lines of ECA-109, Hela-S3 and PANC-1 with the inhibition rates arranging from 50% to 65%.

Andrastone A From the Deep-Sea-Derived Fungus Penicillium allii-sativi Acts as an Inducer of Caspase and RXRα-Dependent Apoptosis.

Two new (1, 2) and one known (3) meroterpenoids were isolated from the deep-sea-derived fungus Penicillium allii-sativi. The relative structures of new compounds were determined on the basis of an extensive analysis of the NMR and MS data, and the absolute configurations were established by ECD calculations. Andrastone A (1) is a rare andrastin bearing an unusual cyclopentan-1,3-dione. It shows a selectively antiproliferative effect against HepG2 tumor cells with an IC50 value of 7.8 µM. Mechanism study showed that apoptosis via Caspase and RXRα pathways are responsible for the inhibitory effect.

Attenuation of Remifentanil-Induced Hyperalgesia by Betulinic Acid Associates with Inhibiting Oxidative Stress and Inflammation in Spinal Dorsal Horn.

Remifentanil-induced hyperalgesia (RIH) is known to be associated with oxidative stress and inflammation. Betulinic acid (BA) was reported to reduce visceral pain owing to its anti-oxidative and anti-inflammatory potential. Here, we -explored whether BA can attenuate RIH through inhibiting oxidative stress and inflammation in spinal dorsal horn. Sprague-Dawley rats were randomly divided into 4 groups: Control, Incision, RIH, and RIH pre-treated with BA. After pretreated with BA (25 mg/kg, i.g.) for 7 days, rats were subcutaneously infused with remifentanil (40 µg/kg) for 30 min during right plantar incision surgery to induce RIH. The paw withdrawal mechanical threshold (PWMT), paw withdrawal thermal latency (PWTL), spinal oxidative stress and inflammatory mediators were determined. Intraoperative remifentanil infusion induced postoperative hyperalgesia, as evidenced by the significant decrease in PWMT and PWTL (p < 0.01), and the significant increase in oxidative stress and inflammation evidenced by up-regulations of malondialdehyde, 3-nitrotyrosine, interleukin-1ß and tumour necrosis factor-α (p < 0.01) in spinal dorsal horn and matrix metalloproteinase-9 (MMP-9) activity (p < 0.01) in dorsal root ganglion, as well as a decrease in manganese superoxide -dismutase activity (p < 0.01) compared with control and -incision groups. All these results mentioned above were markedly reversed by pre-treatment with BA (p < 0.01) compared with RIH group. These findings demonstrated that BA can effectively attenuate RIH, which associates with potentially inhibiting oxidative stress and subsequently down-regulating MMP-9-related pro-inflammatory cyokines in spinal dorsal horn.