Therapeutic Effect of Human Bone Marrow- and Adipose-Derived Stem Cells on Intervertebral Disc Degeneration: A Comparative Study on Rats.

BACKGROUND: Intervertebral disc degeneration (IVD) is a pain-inflicting disorder, posing a serious threat to the elderly, and new therapies are urgently needed. In this study, we examined the potential therapeutic effect of mesenchymal stem cells (MSCs) transplantation on IVD. METHODS: Both human adipose-derived stem cells (hADSCs) and human bone marrow mesenchymal stem cells (hBMSCs) provided by a volunteer were non-contact co-cultured with the human nucleus pulposus cells (hNPCs) to determine the efficacy of hNPCs-oriented differentiation. Flow cytometry was used to characterize the purity of hADSCs/hBMSCs. We determined the expression of surface antigen molecules, such as CD73, CD105, CD90, CD31, HLA-DR, CD34 and CD45, using flow cytometry. Osteogenic and lipogenic differentiations demonstrated by the cells were identified with Alizarin red and Oil red O staining, respectively, and changes in type II collagen and proteoglycan levels were detected by immunofluorescence. Myeloid cell-related mRNA and protein expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. The therapeutic effect of hADSCs and hBMSCs on IVD was evaluated in experimental rats, in which degeneration was induced by needling the annulus fibrosus of the caudal intervertebral disc. RESULTS: As evidenced by the presence of hNPCs-like morphology, both hBMSCs and hADSC could effectively differentiate into hNPCs. Using flow cytometry assays, we found high expression of type II collagen (COL2) and aggrecan (ACAN) protein in the hNPCs-like tissue. Treatment with hADSCs and hBMSCs attenuated IVD progression in the rats, and most importantly, there was no significant difference between the therapeutic effects of both types of cells on IVD, on the basis of the COL2 and SRY-Box Transcription Factor 9 (SOX9) protein expression and the histological results. Findings from the animal studies also suggested that both hADSCs and hBMSCs transplantation could be applied in IVD treatment. CONCLUSIONS: In summary, both hADSCs and hBMSCs can attenuate the progression of IVD by delaying, rather than completely reversing the deterioration of disc degeneration, and there is no significant difference between hADSCs and hBMSCs on the therapeutic effects.

Therapeutic silencing of lncRNA RMST alleviates cardiac fibrosis and improves heart function after myocardial infarction in mice and swine.

Rationale: Cardiac fibrosis is an adverse consequence of aberrant fibroblast activation and extracellular matrix (ECM) deposition following myocardial infarction (MI). Recently, long noncoding RNAs (lncRNAs) have been reported to participate in multiple cardiac diseases. However, the biological functions of lncRNA rhabdomyosarcoma 2-associated transcript (RMST) in cardiac fibrosis remain largely unknown. Methods: The role of RMST in regulating cardiac fibroblast (CF) proliferation, fibroblast-to-myofibroblast transition (FMT), and ECM production, which were induced by transforming growth factor-ß1, was evaluated through immunofluorescence staining, cell contraction assay, cell migration assay, qRT-PCR, and western blot. The therapeutic effect of RMST silencing was assessed in murine and porcine MI models. Results: The present study showed that RMST expression was upregulated and associated with cardiac fibrosis in murine and porcine MI models. Further loss-of-function studies demonstrated that RMST silencing in vitro significantly inhibited CF proliferation, FMT, and ECM production. Accordingly, RMST knockdown in vivo alleviated cardiac fibrosis and improved cardiac contractile function in MI mice. Moreover, RMST acted as a competitive endogenous RNA of miR-24-3p. miR-24-3p inhibition abolished, while miR-24-3p agomir reproduced, the RMST knockdown-mediated effects on CF fibrosis by regulating the lysyl oxidase signaling pathway. Finally, the therapeutic potential of RMST knockdown was evaluated in a porcine MI model, and local RMST knockdown significantly inhibited cardiac fibrosis and improved myocardial contractile function in pigs after MI. Conclusion: Our findings identified RMST as a crucial regulator of cardiac fibrosis, and targeting RMST may develop a novel and efficient therapeutic strategy for treating fibrosis-related cardiac diseases.

tsRNA-04002 alleviates intervertebral disk degeneration by targeting PRKCA to inhibit apoptosis of nucleus pulposus cells.

BACKGROUND: Intervertebral disk degeneration (IDD) is a degenerative disease that underlies various musculoskeletal and spinal disorders and is positively correlated with age. tRNA-derived small RNAs (tsRNA), as a new small noncoding RNAs, its function in IDD is unclear. Herein, our goal was to find the key tsRNA that affects IDD independently of age and explore the underlying mechanisms. METHODS: Small RNA sequencing was performed in nucleus pulposus (NP) tissues of traumatic lumbar fracture individuals, young IDD (IDDY) patients, and old IDD (IDDO) patients. The biological functions of tsRNA-04002 in NP cells (NPCs) were investigated by qRT-PCR, western blot, and flow cytometry analysis. The molecular mechanism of tsRNA-04002 was demonstrated by luciferase assays and rescue experiments. Furthermore, the therapeutic effects of tsRNA-04002 on IDD rat model were used and evaluated in vivo. RESULTS: Compared with fresh traumatic lumbar fracture patients, a total of 695 disordered tsRNAs is obtained (398 down-regulated tsRNAs and 297 up-regulated tsRNAs). These disordered tsRNAs were mainly involved in Wnt signaling pathway and MAPK signaling pathway. tsRNA-04002 was an age-independent key target in IDD, which was both lower expressed in IDDY and IDDO groups than control group. Overexpression of tsRNA-04002 restrained inflammatory cytokines IL-1ß and TNF-α expression, increased the COL2A1, and inhibited the NPCs apoptosis. Furthermore, we determined that PRKCA was the target gene of tsRNA-04002 and was negatively regulated by tsRNA-04002. The rescue experiment results suggested that the high expression of PRKCA reversed the inhibitory effect of tsRNA-04002 mimics on NPCs inflammation and apoptosis, and promotive effect of COL2A1. Moreover, tsRNA-04002 treatment dramatically ameliorated the IDD process in the puncture-induced rat model, together with the blockade of PRKCA in vivo. CONCLUSION: Collectively, our results substantiated that tsRNA-04002 could alleviate IDD by targeting PRKCA to inhibit apoptosis of NPCs. tsRNA-04002 may be a novel therapeutic target of IDD progression.

Therapeutic delivery of microRNA-125a-5p oligonucleotides improves recovery from myocardial ischemia/reperfusion injury in mice and swine.

Rationale: Clinical application of mesenchymal stem cells (MSCs) and MSC-derived exosomes (MSC-Exos) to alleviate myocardial ischemia/reperfusion (I/R) injury is compromised by the low cell engraftment rate and uncontrolled exosomal content. As one of their active ingredients, single-component microRNA therapy may have more inherent advantages. We sought to find an ideal microRNA candidate and determine whether it could reproduce the cardioprotective effects of MSCs and MSC-Exos. Methods: Cardiac function and myocardial remodeling in MSC, MSC-Exo, or microRNA oligonucleotide-treated mouse hearts were investigated after I/R injury. The effects of microRNA oligonucleotides on cardiac cells (macrophages, cardiomyocytes, fibroblasts, and endothelial cells) and their downstream mechanisms were confirmed. Large animals were also employed to investigate the safety of microRNA therapy. Results: The results showed that microRNA-125a-5p (miR-125a-5p) is enriched in MSC-Exos, and intramyocardial delivery of their modified oligonucleotides (agomir) in mouse I/R myocardium, as well as MSCs or MSC-Exos, exerted obvious cardioprotection by increasing cardiac function and limiting adverse remodeling. In addition, miR-125a-5p agomir treatment increased M2 macrophage polarization, promoted angiogenesis, and attenuated fibroblast proliferation and activation, which subsequently contributed to the improvements in cardiomyocyte apoptosis and inflammation. Mechanistically, Klf13, Tgfbr1, and Daam1 are considered the targets of miR-125a-5p for regulating the function of macrophages, fibroblasts, and endothelial cells, respectively. Similar results were observed following miR-125a-5p agomir treatment in a porcine model, with no increase in the risk of arrhythmia or hepatic, renal, or cardiac toxicity. Conclusions: This targeted microRNA delivery presents an effective and safe strategy as a stem cell and exosomal therapy in I/R cardiac repair.

Comparison of lung image quality between CT Ark and Brilliance 64 CT during COVID-19.

AIM: This study is to compare the lung image quality between shelter hospital CT (CT Ark) and ordinary CT scans (Brilliance 64) scans. METHODS: The patients who received scans with CT Ark or Brilliance 64 CT were enrolled. Their lung images were divided into two groups according to the scanner. The objective evaluation methods of signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were used. The subjective evaluation methods including the evaluation of the fine structure under the lung window and the evaluation of the general structure under the mediastinum window were compared. Kappa method was used to assess the reliability of the subjective evaluation. The subjective evaluation results were analyzed using the Wilcoxon rank sum test. SNR and CNR were tested using independent sample t tests. RESULTS: There was no statistical difference in somatotype of enrolled subjects. The Kappa value between the two observers was between 0.68 and 0.81, indicating good consistency. For subjective evaluation results, the rank sum test P value of fine structure evaluation and general structure evaluation by the two observers was ≥ 0.05. For objective evaluation results, SNR and CNR between the two CT scanners were significantly different (P<0.05). Notably, the absolute values ​​of SNR and CNR of the CT Ark were larger than Brilliance 64 CT scanner. CONCLUSION: CT Ark is fully capable of scanning the lungs of the COVID-19 patients during the epidemic in the shelter hospital.

Does vessel length impact transluminal attenuation gradient in 320-slice coronary CT angiography? Correlation with invasive angiography.

OBJECTIVES: This study aimed to investigate the influence of vessel length on transluminal attenuation gradient (TAG) and establish a new index, VLN-TAG (VLN-TAG (HU/100 mm2) = TAG (HU/10 mm)/vessel length (10 mm)), to estimate the diagnostic value using 320-slice computed tomography (CT). METHODS: A total of 150 coronary arteries from 52 patients who underwent single-beat scanning using 320-slice CT and invasive coronary angiography (ICA) within 2 weeks were retrospectively enrolled. TAG was obtained from the major three epicardial vessels, and its interrelation with the measured length of the vessels was evaluated by Pearson correlation and regression analyses. The changes in TAG and VLN-TAG were compared with the corresponding stenosis severities ascertained by ICA using repeated measures ANOVA. RESULTS: TAG had a significant interrelation with the measured length of the vessels (r = 0.644, p < 0.001). Neither TAG nor VLN-TAG with different stenosis degrees of < 50, 50-70, and 70-99% on ICA had significant difference among the three groups. Plaque composition had no influence on VLN-TAG in all groups. The combined TAG or VLN-TAG and coronary computed tomography angiography (CCTA) assessment did not significantly change the area under the curve compared with using CCTA only. In the calcified vessels group, adding VLN-TAG to CCTA improved the specificity (92.86 vs 85.71%). CONCLUSIONS: Vessel length is an important factor impacting TAG. TAG does not offer an incremental diagnostic value compared with CCTA only for detecting coronary stenosis. KEY POINTS: • Transluminal attenuation gradient (TAG) does not improve the diagnostic value of CCTA. Vessel length impacts TAG, but VLN-TAG does not improve the diagnostic value of CCTA. • Plaque composition had no influence on VLN-TAG in all groups of stenosis degrees. There may be a minimal improvement in specificity when VLN-TAG is applied to the calcified vessels group.

Patient-related factors that influence coronary artery density in CCTA: a retrospective clinical study.

OBJECTIVES: The aim of this study was to investigate the relationship between various patient-related factors (physical and cardiac hemodynamic parameters) and the coronary artery density on coronary CT angiography (CCTA). METHODS: A total of 64 patients (female: male ratio, 24:40; age, 58.2 years±9.3, age range, 31-81 years; mean body weight, 65.3 kg±11.6, range 40-88 kg) were effectively enrolled in this approved retrospective study. Patient-related physical factors including height, body weight (BW), body mass index (BMI), systolic blood pressure (BPsys), diastolic blood pressure (BPdis) and blood pulse pressure (Bp) were recorded, measured and calculated prior to the administration of contrast media during the CCTA. Patient-related cardiac hemodynamic parameters, including heart rate (HR), myocardial mass (MM), cardiac output (CO), ejection fraction (EF), end-diastolic dimension (EDV), end-systolic volume (ESV) and stroke volume (SV), were analysed and recorded on the multimodality workplace (MMWP). The mean attenuation values of the left main artery (LMA) were measured and calculated. The correlation of the mean attenuation in the coronary arteries with the physical and hemodynamic parameters was evaluated. The correlations between the physical factors and hemodynamic parameters were also calculated. RESULTS: A significant negative linear correlation was found between the attenuation of the left main artery (LMA) and BW (P=.001), BMI (P=.006), CO (P=.008), EDV (P=.001) and MM (P<.001). Significant linear correlations were obtained between CO and HR (P<.001), EDV and BW (P=.001) and MM and BW (P<.001). CONCLUSION: Coronary artery attenuation depends on the patient's specific physical and cardiac function status.

Multifunctional nanocomposite based on graphene oxide for in vitro hepatocarcinoma diagnosis and treatment.

Because of its unique chemical and physical properties, graphene oxide (GO) has attracted a large number of researchers to explore its biomedical applications in the past few years. Here, we synthesized a novel multifunctional nanocomposite based on GO and systemically investigated its applications for in vitro hepatocarcinoma diagnosis and treatment. This multifunctional nanocomposite named GO-PEG-FA/Gd/DOX was obtained as the following procedures: gadolinium-diethylenetriamine-pentaacetic acid-poly(diallyl dimethylammonium) chloride (Gd-DTPA-PDDA) as magnetic resonance imaging (MRI) probe was applied to modify GO by simple physical sorption with a loading efficiency of Gd(3+) up to 0.314 mg mg(-1). In order to improve its tumor targeting imaging and treatment efficiency, the obtained intermediate product was further modified with folic acid (FA). Finally, the nanocomposite was allowed to load anticancer drug doxorubicin hydrochloride via π-π stacking and hydrophobic interaction with the loading capacity reaching 1.38 mg mg(-1). MRI test revealed that GO-PEG-FA/Gd/DOX exhibit superior tumor targeting imaging efficiency over free Gd(3+). The in vitro release of DOX from the nanocomposite under tumor relevant condition (pH 5.5) was fast at the initial 10 h and then become relatively slow afterward. Moreover, we experimentally demonstrated that the multifunctional nanocomposite exhibited obviously cytotoxic effect upon cancer cells. Above results are promising for the next in vivo experiment and make it possible to be a potential candidate for malignancy early detection and specific treatment.