[Mechanism of Tibetan medicine Pterocephalus hookeri extract in treatment of rheumatoid arthritis based on serum metabonomics].

Ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF/MS) was used to investigate the effect of Pterocephalus hookeri on serum metabolism of adjuvant arthritis(AA) model rats induced by complete Freund's adjuvant. After the AA model was properly induced, the serum of rats was collected 30 days after treatment. UPLC-Q-TOF-MS chromatograms were collected and analyzed by principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). The results revealed that compared with the control group, the model group showed increased content of 12 biomarkers in the serum(P<0.05) and reduced content of the other nine biomarkers(P<0.05). P. hookeri extract could recover the above-mentioned 19 biomarkers to a certain range. Pathway enrichment showed that these markers mainly involved eight metabolic pathways, including valine, leucine, and isoleucine degradation, arachidonic acid metabolism, arginine and proline metabolism, glycerol phospholipid metabolism, primary bile acid biosynthesis, bile acid biosynthesis, tryptophan metabolism, and unsaturated fatty acid biosynthesis. The findings of this study demonstrate that P. hookeri extract can regulate metabolic disorders and promote the regression of metabolic phenotype to the normal level to exert the therapeutic effect on AA rats. This study is expected to provide a certain scientific basis for the biological research on the treatment of rheumatoid arthritis by P. hookeri.

Glucocorticoid-induced dose-related and site-specific bone remodelling, microstructure, and mechanical changes in cancellous and cortical bones.

The study investigated the effects of long-term glucocorticoid (GC) administration on bone remodelling, microstructure, and biomechanical strength in cortical and cancellous (trabecular) bones. Thirty-one female Sprague-Dawley rats were randomly divided into three dexamethasone (Dex) dosage groups, 1.0, 2.5, and 5.0 mg/kg twice a week for 8 weeks, and one control group treated with saline. At the end of the experiment, the tibia of one side and the fourth lumbar vertebrae were processed into sections for a histomorphometric analysis, while the femur of the same side and the fifth vertebrae were isolated for a biomechanical test. A dose-dependent decline in bone formation was observed in both trabecular and cortical (periosteal and endosteal) bones. In contrast, bone resorption was inhibited only in cancellous bone in the two higher dose groups and not dose-related. The ratio of Node/Termini increased, while marrow star volume (MSV) decreased in all Dex groups in metaphyseal trabecular bones, both of which were dose-dependent. Subendosteal cortex porosity increased in parallel with non-uniform trabecular distribution, but cortical thickness remained unchanged. Interestingly, there were no significant changes in microstructure or mechanical strength in lumbar trabecular bone. The cortical elastic load was dose-independently reduced in all three Dex groups when compared with the control group. In summary, bone remodelling was dose-dependently inhibited in cancellous bones but enhanced in intracortical bones. The non-uniform distribution of trabecular bone and increased porosity in the inner edge of cortical bone were both in parallel with GC dosage, and the porosity increase was more likely to occur, leading to reduced cortical mechanical strength.

Pterocephanoside A, a new iridoid from a traditional Tibetan medicine, Pterocephalus hookeri.

This work obtained and identified pterocephanoside A (1), one new iridoid glucoside derivative with rare structure of three iridoid glycosides linked to cyclopenta[c]pyran-3(1H)-one, and 10 known iridoids (2-11) from Pterocephalus hookeri through silica gel column chromatography and semi-preparative HPLC. The structure of the new compound was confirmed by 1D and 2D NMR and HRMS data analysis. Compounds 1 and 2 were isolated from this plant for the first time. The iridoids mostly possessed seco-iridoid subtype and iridoid subtype skeletons from P. hookeri. Compounds 1, 3, 4, and 6-11 showed weak anti-inflammatory activity.

The development of bone microstructure, metabolism and biomechanics in lumbar vertebra under short-term glucocorticoid exposure.

Abstracts Objective: This study investigated the characteristics of bone microstructure, metabolism, and biomechanics in rat's lumbar vertebra undergoing short-term glucocorticoid administration. Methods: Forty 4-month-old female Sprague-Dawley rats were treated with either vehicle (Cont) or prednisone acetate (Pre) at 3.5 mg/kg/day, respectively for periods of 7 days and 21 days. The lumbar vertebras were processed for MicroCT scan, histomorphometry analysis, mechanical compression test, in addition to Dual-Energy X-ray absorptiometry scan, respectively. Results: The connective density (Conn. D) along with trabecular connection nodes decreased while trabecular termini increased in Pre at day 21 when compared to Cont at day 21 as well as Pre at day 0. The mineralizing surface (MS/BS), mineral apposition rate (MAR), bone formation rate (BFR), osteoblast surfaces (Ob.S/BS) were lower in Pre at day 21 than that in Cont at day 21, Pre at day 0 and Pre at day 7. Only the bending stiffness of compression test decreased in Pre group at day 21 compared to age-matched control. Conclusion: The results suggested that excess prednisone significantly inhibited bone formation and slightly depressed bone resorption in the lumbar vertebra of intact rats for the duration of 21 days. Accordingly, the trabecular spatial microstructure made an adjustment yet failed to maintain the anti-compression mechanical property.

Salvianolic acid B stimulates osteogenesis in dexamethasone-treated zebrafish larvae.

AIM: Our previous studies show that salvianolic acid B (Sal B) promotes osteoblast differentiation and matrix mineralization. In this study, we evaluated the protective effects of Sal B on the osteogenesis in dexamethasone (Dex)-treated larval zebrafish, and elucidated the underlying mechanisms. METHODS: At 3 d post fertilization, wild-type AB zebrafish larvae or bone transgenic tg (sp7:egfp) zebrafish larvae were exposed to Sal B, Dex, or a mixture of Dex+Sal B for 6 d. Bone mineralization in AB strain larval zebrafish was assessed with alizarin red staining, and osteoblast differentiation in tg (sp7:egfp) larval zebrafish was examined with fluorescence scanning. The expression of osteoblast-specific genes in the larvae was detected using qRT-PCR assay. The levels of oxidative stress markers (ROS and MDA) in the larvae were also measured. RESULTS: Exposure to Dex (5-20 µmol/L) dose-dependently decreased the bone mineralization area and integral optical density (IOD) in wild-type AB zebrafish larvae and the osteoblast fluorescence area and IOD in tg (sp7:egfp) zebrafish larvae. Exposure to Dex (10 µmol/L) significantly reduced the expression of osteoblast-specific genes, including runx2a, osteocalcin (OC), alkaline phosphatase (ALP) and osterix (sp7), and increased the accumulation of ROS and MDA in the larvae. Co-exposure to Sal B (0.2-2 µmol/L) dose-dependently increased the bone mineralization area and IOD in AB zebafish larvae and osteoblast fluorescence in tg (sp7:egfp) zebrafish larvae. Co-exposure to Sal B (2 µmol/L) significantly attenuated deleterious alterations in bony tissue and oxidative stress in both Dex-treated AB zebafish larvae and tg (sp7:egfp) zebrafish larvae. CONCLUSION: Sal B stimulates bone formation and rescues GC-caused inhibition on osteogenesis in larval zebrafish by counteracting oxidative stress and increasing the expression of osteoblast-specific genes. Thus, Sal B may have protective effects on bone loss trigged by GC.

[Study on effect of total flavonoids of Oldenlendia difflusa on ulcerative colitis and its immunological mechanism].

OBJECTIVE: To observe the effect of total flavonoids of Oldenlendia difflusa (FOD) on NF-kappaB and IL-8, TNF-alpha, IL-10 expressions of ulcerative colitis (UC) model rats, and explore its immunological mechanism of anti-UC. METHOD: Sixty Kunming male mice with the average weight of (20 +/- 2) g were randomly divided into six groups. The control group (cont) was orally administered with distilled water. Whereas the remaining five groups were fed with 4% dextran sulphate sodium (DSS) solution for seven days to induce acute UC, and orally administered with the following drugs: distilled water (for the DSS group), SASP at dose of 500 mg x kg(-1) x d(-1) for the DSS + SASP group, FOD at dose of 60 mg x kg(-1) x d(-1) for the DSS + FOD-H group, FOD at dose of 40 mg x kg(-1) x d(-1) for the DSS + FOD-M group, and FOD at dose of 26.7 mg x kg(-1) x d(-1) for the DSS + FOD-L group. During the modeling and drug administration, the mice were scored for DAI. Seven days later, the mice were put to death, and their colonic tissue samples were collected to evaluate colonic mucosal lesions. The NF-kappaB p65, IL-8, TNF-alpha, IL-10 expressions were tested by immunohistochemical staining and ELISA. RESULT: Seven-day feeding with 4% DSS solution could successfully induce acute UC in mice. Compared with the cont group, the DSS group showed significantly higher DAI and colonic mucosal lesions, remarkable increase in NF-kappaB p65, IL-8, TNF-alpha expression in colonic tissues, and notable decrease in IL-10 expression (P < 0.05). FOD could prevent acute UC in mice included by DSS. Seven-day administration of 60 mg x kg(-1) x d(-1) or 40 mg x kg(-1) x d(-1) FOD could completely or partially resist the above mentioned changes caused by DSS. Compared with the DSS group, the DSS + FOD-H group and the DSS + FOD-M group showed reduction in colonic mucosal lesions, down-regulation in IL-8, TNF-alpha and NF-kappaB p65 expressions and up-regulation in IL-10 expression (P < 0.05). CONCLUSION: FOD could significantly resist UC in mice. Its mechanism may be related to the inhibition of NF-kappaB p65 activation, the reduction of IL-8 and TNF-alpha expressions and the increase in the anti-inflammatory factor IL-10.

Chlorogenic acid, a natural product as potential inhibitor of COVID-19: virtual screening experiment based on network pharmacology and molecular docking.

Chlorogenic acid (CGA) is a potential inhibitor of Coronavirus Disease 2019 (COVID-19). ACE2 and its co-expressed proteins are SARS-CoV-2 receptors, which have been linked to SARS-CoV-2 infection and considered as the key target of SARS-CoV-2 in entering target cells. Here, network pharmacology was used to investigate the mechanism by which CGA affected COVID-19. A total of 70 potential targets related to the treatment of COVID-19 were obtained, among which NFE2L2, PPARG, ESR1, ACE, IL6, and HMOX1 might be the main potential targets. Finally, CGA and potential target proteins were scored by molecular docking, and the prediction results of network pharmacology were preliminarily verified. Moreover, CGA had potential anti-SARS-CoV-2 activity via integrating three common receptors in clinical practice compared with clinical trial drugs registered for the treatment of COVID-19, as shown by molecular docking. The mechanism of CGA against COVID-19 was initially investigated using network pharmacology, followed by molecular docking.

Effect of androgen on bone metabolism in hyperuricemic rats.

Introduction: This study aimed to investigate the effect of androgen on bone metabolism in hyperuricemic rats. Material and methods: Forty male Wistar rats were randomly divided into four groups: sham operation group, simple hyperuricemic group, hyperuricemic castration group, and simple castration group. A rat model of chronic hyperuricemia was established using potassium oxonate and ethambutol. Blood was sampled from the vena angularis at week 0, 4, 6, 8 and 12 after surgery to detect for uric acid, calcium, phosphorus and alkaline phosphatase, and investigate the effect of androgen on bone metabolism in hyperuricemic rats. Results: From the 4th week, compared with the sham operation group, the differences in uric acid levels between the simple hyperuricemic group and hyperuricemia castration group were statistically significant (p < 0.05), suggesting the successful establishment of the model of hyperuricemia. At the 6th week, uric acid levels decreased in the two hyperuricemic groups, and the difference from the sham operation group decreased (p = 0.05), showing that the modeling method had deteriorated. At the 8th week, the differences in uric acid levels between the two castration groups and sham operation group were statistically significant (p < 0.05). At the 12th week, the differences in serum levels of phosphorus between the simple hyperuricemic group and hyperuricemic castration group were statistically significant (p < 0.05). Conclusions: Androgen can induce bone metabolism changes in rats with hyperuricemia.

Autophagy plays a protective role in cell death of osteoblasts exposure to lead chloride.

Lead (Pb) is a toxic heavy metal widespreadly used in industrial field. Prior studies showed that Pb exposure had detrimental effects on osteoblasts. The mechanisms underlying Pb-induced damage are complex. Autophagy can protect cells from various cytotoxic stimuli. In the present study, the aim of our research was to investigate whether Pb could activate autophagy to play a protective role against osteoblasts apoptosis. Our results indicated that PbCl2 induced autophagy and autophagic flux in MC3T3-E1 murine osteoblastic cell by RT-PCR, western blot, as well as fluorescence microscopy analysis of GFP-LC3, AO and MDC staining. Pb increased the apoptosis of osteoblasts, evidenced by western blot and Hoechst 33258 staining assessment. In addition, inhibiting autophagy by 3-MA further increased the osteoblasts apoptosis after Pb exposure, showed by flow cytometry and Hoechst 33258 staining. Furthermore, phosphorylation of mTOR and p70S6K was inhibited by Pb exposure, indicating that Pb might induce autophagy in osteoblasts via inhibiting mTOR pathway. Altogether, these evidence suggested that Pb exporsure promoted autophagy flux in osteoblasts. The activation of autophagy by Pb played a protective role in osteoblasts apoptosis, which might be mediated through the mTOR pathway.