M13, an anthraquinone compound isolated from Morinda officinalis promotes the osteogenic differentiation of MSCs by targeting Wnt/β-catenin signaling

BACKGROUND

Morinda officinalis (MO) is a herb used in Traditional Chinese Medicine (TCM) for the treatment of osteoporosis. M13, a MO-based anthraquinone compound is known to suppress osteoclast activity. However, whether M13 promotes MSCs osteogenic differentiation and its potential mechanism remains unknown.

PURPOSE

To examine the influence of M13 on MSCs proliferation and osteogenic differentiation and elucidate the underlying mechanism.

METHODS/STUDY DESIGNS

The effect of M13 exposure on MSCs proliferation was assessed via CCK8 assay, clone formation assay, immunofluorescence, RT-qPCR, and Western blot. The M13-mediated osteogenesis in vitro and ex vivo were evaluated via ALP and Alizarin red S staining, osteogenesis-associated gene (Runx2, Col1a1 and Opn) expression, and fetal limb explants culture. Molecular docking was employed for target signal pathway screening. The potential signaling mechanisms of M13-promoted MSCs osteogenic differentiation were analyzed by introducing XAV939 (Wnt/β-catenin signaling inhibitor).

RESULTS

M13 induced certain obvious positive effects on MSCs proliferation and osteogenic differentiation. Treatment with M13 enhanced MSCs viability and clone numbers. Meanwhile, M13 promoted osteogenic gene expression, enhanced ALP intensity and Alizarin red S staining in MSCs. In terms of mechanism, M13 strongly interacted with the docking site of the WNT signaling complex, thereby activating the Wnt/β-catenin pathway. Furthermore, the M13-mediated osteogenic effect was partially inhibited by XAV939 both in vitro and ex vivo, which confirmed that the Wnt/β-catenin axis is a critical regulator of M13-induced osteogenic differentiation of MSCs.

CONCLUSION

Our study elucidated for the first time that M13 significantly promoted osteogenic differentiation of MSCs via stimulation of the Wnt/β-catenin pathway in vitro and ex vivo.Our findings offered new additional evidence to support the MO or M13-based therapy of osteoporosis.

Anti-neuroinflammatory 3-hydroxycoumaronochromones and isoflavanones enantiomers from the fruits of Ficus altissima Blume

A phytochemical study on the fruits of Ficus altissima Blume (lofty fig) led to the isolation and structural elucidation of three pairs of enantiomeric 3-hydroxycoumaronochromones and two pairs of enantiomeric isoflavanones, including eight undescribed compounds. Their structures were determined based on a comprehensive analysis of NMR and HR-ESI-MS spectroscopic data, calculated ¹³C NMR-DP4 plus analysis and the comparisons of experimental measurements of ECD with calculated ECD spectra by TDDFT or ECD plots in reported protocols. The inhibitory effects of the isolated enantiomers on NO production stimulated by LPS in microglial BV-2 cells were evaluated. Among them, ficusaltin D exhibited the most potent anti-neuroinflammatory activity, which inhibited the production of NO and the expression of iNOS, IL-6 and IL-1β and suppressed the NF-κB nuclear translocation in LPS-induced BV-2 cells, while its enantiomer displayed cytotoxicity.

Filtration efficiency of N95 filtering facepiece respirators during multi-cycles of '8-hour simulated donning + disinfection'

BACKGROUND

Aerosol-borne diseases such as COVID-19 may outbreak occasionally in various regions of the world, inevitably resulting in short-term shortage and corresponding reuse of disposable respirators.

AIM

To investigate the effective disinfection methods, reusable duration and frequency of N95 respirators.

METHODS

Based on the self-built respirator simulation test system, and under combinations of experimental conditions of three N95 respirators × 0-200 nm NaCl aerosols × three simulated breathing flow rates (15, 50 and 85 L/min) × two disinfection methods (dry heating and ultraviolet (UV) radiation), this study continuously measured the changes in filtration efficiency of all respirators during multi-cycles of '8-h simulated donning + disinfection' until the penetration reached ≥5%.

FINDINGS

Multi-cycles of dry heating and UV radiation treatments on the reused (i.e., multiple 8-h donning) N95 respirators had a minimal effect (<0.5%) on the respirator filtration efficiency, and even at 85 L/min, all tested N95 respirators were able to maintain filtration efficiencies ≥95% for at least 30 h or four reuse cycles of '8-h donning + disinfection', while a lower breathing flow rate (15 L/min) plus the exhalation valve could further extend the N95 respirator's usability duration up to 140 h or 18 reuse cycles of '8-h donning + disinfection'. As the respirator wearing time extended, aerosol penetration slowly increased in a quadratic function with a negative second-order coefficient, and the penetration increment during each cycle of 8-h donning was less than 0.9%.

CONCLUSION

Multi-cycles of N95 respirator reuse in combination with dry heating or UV irradiation disinfection are feasible.

[Investigation of the occurrence of musculoskeletal disorders at shoulder, neck and elbow of digestive endoscopy operators]

Objective: To investigate the effect of endoscopic operation volume on musculoskeletal disorders (MSDs) of shoulder, neck and elbow. Methods: From December 2019 to March 2020, random sampling was used to select 200 gastroenterologists from hospitals at or above the municipal level in Sichuan Province as the research object. Gastroenterologists were divided into 108 eadoscop in the low operation group (The operation volume is less than 5 000 cases) and 92 eadoscop in the high operation group (The operation volume is more than 5 000 cases) according to the operation volume. MSDS was investigated by UCLA shoulder scoring system, Tanaka Jingjiu cervical spondylosis scale and improved An and Morrey elbow scoring system, and the chi-square test was used to compare the basic conditions of different body parts in the two groups. The basic condition of each part of the two groups was tested and compared. Results: Compared with the low operation group, the age and working years of the high operation group were longer, and the difference was statistically significant (P<0.001). The most painful part between the two groups was the shoulder, accounting for 25.9% (28/108) and 37.0% (34/92), respectively. Occasional shoulder pain was the most (41.9%, 26/62) and normal function was the most (32.3%, 20/62) ; The forward flexion angle exceeds 150° at most (40.3%, 25/62). Slight pain often occurred in the neck, accounting for 57.7% (15/26), the occasional impact of pain on the upper limbs accounted for 61.5% (16/26), and the impact on the fingers accounted for 53.8% (14/26) ; 65.0% (15/26) had mild disturbance to the sense of signs; Normal tendon reflex accounted for 88.5% (23/26) ; The influence of opponents was weakness, discomfort and no dysfunction, accounting for 53.8% (14/26) ; Endoscopists with normal muscle strength (2 points) and mild decline accounted for 50.0% (13/26) respectively, and there was no significant difference among the groups (P=0.234、1.000、1.000、0.050、0.680、0.539、0.431、0.239). The elbow score scale showed that mild loss accounted for 55.0% (11/20), mild instability accounted for 65% (13/20), and mild pain accounted for 55.0% (11/20) . Conclusion: MSDs is a health problem faced by endoscopists, and targeted preventive measures should be taken for its possible causes.

AB0139 DEEP IMMUNE PHENOTYPING OF T LYMPHOCYTE SUBSETS IN SYSTEMIC SCLEROSIS PATHOPHYSIOLOGY AND FOLLOWING RESPONSE TO TARGETED CYTOTOXIC TREATMENT

Background

Abnormalities in T lymphocyte populations are associated with the pathogenesis of many autoimmune diseases, such as systemic sclerosis (SSc). Various studies report on the aberrations of different T cell cytotoxic (CTL) and helper (Th) subsets that appear to be linked with inflammatory and/or fibrotic manifestations of patients with SSc. Since T cells seem to play a pivotal role in the pathophysiology of SSc, targeting the pathogenic T cell subsets might be a promising therapeutic option.

Objectives

Here we set out to comprehensively compare T lymphocyte phenotypes between SSc patients and healthy donors. We further test the in-vitro efficacy of a combination of anti-CD3/CD7 immunotoxins (CD3/CD7-IT), that have been developed to eliminate activated CD4+ and CD8+ T cells, to study specific sensitivity of T-cell subpopulations to CD3/CD7-IT.

Methods

30 SSc patients and 15 age and sex matched healthy donors were included. Of these patients, lymphocyte populations were quantified by 17-parameter flow cytometry of peripheral blood mononuclear cells (PBMCs) to identify CD4+ T helper cells (Th1, Th2, Th17, T peripheral helper), CD8+ naïve, memory, effector CTLs and senescent/exhausted subsets. We next developed a cell killing assay to evaluate the effect of T cell depletion. To address this, patients’ (N=6) PBMCs were first activated for 24 hours in the presence of phytohemagglutinin, followed by CD3/CD7-IT addition for 48 hours. Subset-specific T cell depletion was assessed by using a combination of CellTiter-Glow luminescent cell viability assay and multi-parameter flow cytometric (FCM) quantification of CD3/CD7-IT-induced cell death.

Results

Frequencies of effector CD8+ CTLs,Th2 and T peripheral helper cells were elevated in SSc patients compared to healthy controls. Furthermore, SSc patients exhibited lower percentages of the anti-fibrotic Th1 subset. A striking expansion of the senescent CD4+CD28- and CD8+CD28- populations was noted in patients, while these subsets were barely detectable in healthy controls. In-vitro adittion of anti-T cell immunotoxins effectively depleted 50 % of patients’ CD8+ T cells (including the CD8 effector subset) and 62% of CD4+ T cells (including Th2 and T peripheral helper cells). No difference in cytolytic sensitivity between different T cell subsets was observed.

Conclusion

Our findings demonstrate that deep FCM immunephenotyping reveals pathophysiological differences in peripheral T cell subsets of SSc patients. Strikingly, the developed cytolytic assays show that CD3/CD7-IT is able to target the potential disease-associated T cell subsets in an in-vitro setting.

References

Not applicable

Disclosure of Interests

None declared

Antiproliferative Amaryllidaceae alkaloids from the bulbs of Hymenocallis littoralis (Jacq.) Salisb

Seven undescribed Amaryllidaceae alkaloids classified into four types, including the plicamine-type, secoplicamine-type, belladine-type and pretazettine-type, along with another three alkaloids that have not been isolated from plant material and seven known alkaloids, were isolated from the bulbs of Hymenocallis littoralis (Jacq.) Salisb. The structures were elucidated on the basis of various spectroscopic methods (UV, IR, MS, NMR, ECD). The isolated alkaloids were screened for antiproliferative activity against four human tumour cell lines (HepG2, HeLa, SPC-A-1, FaDu) through MTT assay, and some alkaloids exhibited potent cytotoxicity. Meanwhile, cell morphological assessment, flow cytometric analysis, Western blot analysis, clone formation and scratch wound assays were utilized for an undescribed belladine-type alkaloid and two known alkaloids, which had antiproliferative effects on the HepG2 cell line via induction of apoptosis in a dose-dependent manner. A pair of diastereoisomers of Amaryllidaceae alkaloids exhibited significant differences in antiproliferative activity. In addition, the alkaloids also possessed the potential to inhibit tumour cell migration.

Untargeted lipidomics analysis in women with intrahepatic cholestasis of pregnancy: a cross-sectional study

OBJECTIVE

To compare the plasma lipid profiles in women with normal pregnancies and those with mild or severe intrahepatic cholestasis of pregnancy (ICP). Our goal was to reveal lipidome-wide alterations in ICP and delve into the pathogenesis of ICP from a lipid metabolism perspective.

DESIGN

Cross-sectional study, including women with normal pregnancies, women with mild ICP and women with severe ICP.

SETTING

Gansu Provincial Hospital.

POPULATION

Women with ICP were recruited from October 2019 to March 2020 in Gansu, China.

METHODS

Untargeted lipidomics was used to analyse differentially expressed plasma lipids in controls, in women with mild ICP and in women with severe ICP (n = 30 per group). For lipidomics, liquid chromatography and Q-Exactive Plus Orbitrap mass spectrometry were performed.

MAIN OUTCOME MEASURES

Differentially expressed lipids.

RESULTS

Thirty-three lipids were differentially expressed in the severe and mild ICP groups, compared with the control group, and 20 of those were sphingolipids (ceramide, six species; sphingomyelin, 14 species). All differentially expressed sphingolipids in women with mild ICP were also differentially expressed in women with severe ICP; the fold change and significance of the differential expression were positively correlated with disease severity.

CONCLUSIONS

We systematically characterized the lipidome-wide alterations in mild and severe ICP groups. The results indicated a link between ICP and disordered sphingolipid homeostasis.

TWEETABLE ABSTRACT

Abnormal sphingolipid metabolism is involved in the pathogenesis of ICP.