Oroxin B alleviates osteoarthritis through anti-inflammation and inhibition of PI3K/AKT/mTOR signaling pathway and enhancement of autophagy.

Background: Osteoarthritis (OA) is a common aging-related degenerative joint disease with chronic inflammation as its possible pathogenesis. Oroxin B (OB), a flavonoid isolated from traditional Chinese herbal medicine, possesses anti-inflammation properties which may be involved in regulating the pathogenesis of OA, but its mechanism has not been elucidated. Our study was the first to explore the potential chondroprotective effect and elucidate the underlying mechanism of OB in OA. Methods: In vitro, primary mice chondrocytes were stimulated with IL-1ß along with or without the administration of OB or autophagy inhibitor 3-methyladenine (3-MA). Cell viability assay was measured with a cell counting kit-8 (CCK-8). The phenotypes of anabolic-related (Aggrecan and Collagen II), catabolic-related (MMP3, MMP13, and ADAMTS5), inflammation-related (iNOS, COX-2, TNF-α, IL-6, and IL-1ß), and markers of related signaling pathways in chondrocytes with different treatment were detected through western blot, RT-qPCR, and immunofluorescent staining. In vivo, the destabilized medial meniscus (DMM) operation was performed to establish the OA mice model. After knee intra-articular injection with OB for 8 weeks, the mice's knee joints were obtained for subsequent histological staining and analysis. Results: OB reversed the expression level of anabolic-related proteins (Aggrecan and Collagen II) and catabolic-related (MMP3, MMP13, and ADAMTS5) in IL-1ß-induced chondrocytes. Mechanistically, OB suppressed the inflammatory response stimulated by IL-1ß, as the inflammation-related (iNOS, COX-2, TNF-α, IL-6, and IL-1ß) markers were downregulated after the administration of OB in IL-1ß-induced chondrocytes. Besides, the activation of PI3K/AKT/mTOR signaling pathway induced by IL-1ß could be inhibited by OB. Additionally, the autophagy process impaired by IL-1ß could be rescued by OB. What's more, the introduction of 3-MA to specifically inhibit the autophagic process impairs the protective effect of OB on cartilage. In vivo, histological staining revealed that intra-articular injection of OB attenuated the cartilage degradation, as well as reversed the expression level of anabolic and catabolic-related proteins such as Aggrecan, Collagen II, and MMP13 induced in DMM-induced OA models. Conclusions: The study verified that OB exhibited the chondroprotective effect by anti-inflammatory, inhibiting the PI3K/AKT/mTOR signaling pathway, and enhancing the autophagy process, indicating that OB might be a promising agent for the treatment of OA.

[Application of rapid PCR to authenticate Ranae Oviductus].

Rapid allele-specific PCR primer was designed base on Cytb 155 A/T single nucleotide polymorphism, DNA was extracted by alkaline lysis and the PCR reaction systems including denatured and annealing temperature and cycle numbers were optimized. The results were performed to authenticate Ranae Oviductus and its 4 adulterants. When 100×SYBR Green I was added in the PCR product at 90 ℃ denatured 3 s, 62 ℃ annealing 20 s and 32 cycle. Ranae Oviductus visualized strong green fluorescence under 365 nm UV lamp whereas adulterants appeared negative. The whole process can be completed in 40 minutes．The established method provides the technical support for authentication of the Ranae Oviductus.

The effect of N-acetylcysteine on exacerbations of chronic obstructive pulmonary disease: A meta-analysis and systematic review.

N-acetylcysteine (NAC) is an antioxidant and anti-inflammatory. Its effects on chronic obstructive pulmonary (COPD) outcomes, including exacerbation of and changes in lung function parameters, are controversial. To investigate the effects of NAC on COPD exacerbation and changes in lung function parameters in patients with COPD. A meta-analysis of randomized controlled trials retrieved from PubMed and Medline databases (12 trials; 2691 patients). High-dose [relative ratio (RR) = 0.90, 95% confidence interval (CI) = 0.82-0.996, P = 0.041] and low-dose (RR = 0.83, 95% CI = 0.69-0.99, P = 0.043) NAC reduced COPD exacerbation prevalence. Long-term (≥6 months), but not short-term, NAC reduced exacerbation prevalence (RR = 0.85, 95% CI = 0.74-0.98, P = 0.024). NAC did not affect exacerbation rate, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), or inspiratory capacity (IC). Long-term NAC therapy may reduce risk of COPD exacerbation.

Repeated intra-nigrostriatal injection of phorbol myristate acetate induces microglial senescence in adult rats.

Phorbol myristate acetate (PMA), as a potent tumor promoter, may induce microglial senescence. The present study investigated the effect of PMA infection on microglial senescence. From 58 male Sprague­Dawley rats, 10 were randomly selected and divided into a PMA injection group, containing five rats (0.5 µg/µl PMA) and a control group, containing five rats (commensurable 0.9% saline). Immunofluorescent staining of Iba­1 and enzyme­linked immunosorbent assay analyses of the expression levels of tumor necrosis factor (TNF)­α and interleukin (IL)­1 ß were performed in these two groups. The remaining 48 rats were randomly divided into the following three groups, each containing 16 rats: Repeated injection control group (commensurable normal saline, once a week for 4 weeks), single PMA injection group (0.5 µg/µl PMA, once in the first week) and repeated injection PMA group (0.5 µg/µl PMA, once a week for 4 weeks). The expression levels of p21, detected using double immunofluorescence staining with Iba­1, and ß­galactosidase, via double immunohistochemical staining of Iba­1, were examined in these three groups. The results indicated that a single injection of PMA did not change the microglial morphology and had no significant effects on the expression levels of TNF­α and IL­1ß, compared with the control group (P>0.05). Following four repeated injections of PMA, the microglia in the substantia nigra presented with features of senescence, characterized by increased expression levels of ß-galactosidase (P<0.001) and p21 (P<0.001), compared with the repeated injection control group. In conclusion, repeated intra-nigrostriatal treatment with PMA induced microglial senescence with increased expression levels of ß-galactosidase and p21 in the substantia nigra of the rats.

[Erythromycin inhibits elastin peptides-induced differentiation of CD4⁺T cells into Th17 cells].

OBJECTIVE: To investigate the effect of erythromycin on differentiation into T helper 17 (Th17) cells from CD4⁺T cells exposed to elastin peptides. METHODS: The CD4⁺T cells from spleen of male BALB/c mice by magnetic bead sorting were randomly divided into the control group (group A), the elastin peptides group (group B) and erythromycin group(group C). The cells in group B and C were cultured in serum-free medium supplemented with 30 µg/mL elastin peptides. The cells in group C were additionally administrated with erythromycin at a dose of 100 µg/mL. All of the CD4⁺T cells were cultured in serum-free culture solution for 24 hours. The number of the Th17 cells was detected by flow cytometry and the expression of retinoic acid related orphan nuclear receptor γt (RORγt) mRNA was measured by fluorescence quantitative PCR in each group. The expressions of NF-κB(p65) and signal transducer and activator of transcription 3 (STAT3) were analyzed by Western blotting. RESULTS: The Th17 cells in group B [(11.32 ± 2.34)%] increased as compared with that in group A [(5.21 ± 1.36)%], and the expression of RORγt mRNA in group B was higher than that in group A. Furthermore, the expressions of NF-κB(p65) and STAT3 proteins in group B increased significantly as compared with those in group A. However, compared with group B, group C presented with the significantly decreased expressions of Th17 cells, RORγt mRNA, NF-κB(p65) and STAT3 proteins. CONCLUSION: Erythromycin can suppress the differentiation into Th17 cells from CD4⁺T cells exposed to elastin peptides.

A novel mutation of the nicotinic acetylcholine receptor gene CHRNA4 in sporadic nocturnal frontal lobe epilepsy.

SUMMARY: Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is known to be partly caused by mutations in the transmembrane domain (TM) 1-3 of the genes of the neuronal nicotinic acetylcholine receptor (nAChR) alpha4-subunit (CHRNA4), beta2-subunit (CHRNB2) and alpha2-subunit (CHRNA2). The more common cases of sporadic nocturnal frontal lobe epilepsy (NFLE) that are not differentiated from ADNFLE by phenotype have been found to be associated with the mutation of CHRNA4 reported in ADNFLE. In order to assess the genetic defects in NFLE, we performed a mutation screening in 33 unrelated patients with sporadic NFLE by amplifying and sequencing bidirectionally TM 1-3 of CHRNA4, CHRNB2 and CHRNA2 which contain the mutations reported in ADNFLE. In screening CHRNA4, we identified a novel mutation in one patient that causes a alpha4-R308H amino acid exchange outside the TM, and in the second intracellular loop between the third and fourth transmembrane domains. The mutation was not observed in 400 control chromosomes. No mutations were present in parts of CHRNB2 and CHRNA2.