CD206+ M2-like macrophages protect against intervertebral disc degeneration partially by targeting R-spondin-2.

OBJECTIVE: This study aimed to explore the specific function of M2 macrophages in intervertebral disc degeneration (IDD). METHODS: Intervertebral disc (IVD) samples from normal (n = 4) and IDD (n = 6) patients were collected, and the expression of M2-polarized macrophage marker, CD206, was investigated using immunohistochemical staining. Nucleus pulposus cells (NPCs) in a TNF-α environment were obtained, and a mouse caudal IVD puncture model was established. Mice with Rheb deletions, specifically in the myeloid lineage, were generated and subjected to surgery-induced IDD. IDD-induced damage and cell apoptosis were measured using histological scoring, X-ray imaging, immunohistochemical staining, and TdT-mediated dUTP nick end labeling (TUNEL) assay. Finally, mice and NPCs were treated with R-spondin-2 (Rspo2) or anti-Rspo2 to investigate the role of Rspo2 in IDD. RESULTS: Accumulation of CD206 in human and mouse IDD tissues was detected. Rheb deletion in the myeloid lineage (RheBcKO) increased the number of CD206+ M2-like macrophages (mean difference 18.6% [15.7-21.6%], P < 0.001), decreased cell apoptosis (mean difference -15.6% [-8.9 to 22.2%], P = 0.001) and attenuated the IDD process in the mouse IDD model. NPCs treated with Rspo2 displayed increased extracellular matrix catabolism and apoptosis; co-culture with a conditioned medium derived from RheBcKO mice inhibited these changes. Anti-Rspo2 treatment in the mouse caudal IVD puncture model exerted protective effects against IDD. CONCLUSIONS: Promoting CD206+ M2-like macrophages could reduce Rspo2 secretion, thereby alleviating experimental IDD. Rheb deletion may help M2-polarized macrophages accumulate and attenuate experimental IDD partially by inhibiting Rspo2 production. Hence, M2-polarized macrophages and Rspo2 may serve as therapeutic targets for IDD.

Macrophage polarization and macrophage-related factor expression in hypertrophy of the ligamentum flavum.

PURPOSE: Owing to the unknow types of infiltrating macrophages and the corresponded factors, we aimed to investigate the specific types of infiltrating macrophages involved in HLF and the expression of macrophage-related factors. METHODS: The ligamentum flavum was obtained from patients with lumbar spinal stenosis (HLF group; n = 15) and lumbar disc herniation (non-hypertrophic ligamentum flavum [NLF] group; n = 15). Ligamentum flavum specimens were paraffin embedded, followed by histological and immunohistochemical staining to identify the macrophage type and expression of macrophage-related factors. RESULTS: The HLF group demonstrated CD206 marker expression, while the NLF group did not (P < 0.0001; n = 11). CD68 marker was expressed in both groups (P > 0.05; n = 11). CCR7 was not expressed in either group. The expression levels of the extracellular matrix proteins aggrecan (Agg), type I collagen (Coll1), and type II collagen (Coll2) were higher in the HLF group than in the NLF group (P < 0.0001; n = 11). The aging markers p21, p16, and p53 were expressed in the HLF group, but not in the NLF group (P < 0.0001; n = 11). The expression levels of the inflammatory factors TNF-α and IL-1ß were higher in the HLF group than in the NLF group (P < 0.0001; n = 11). Similarly, the expression level of the fibrosis factor TGF-ß1 was higher in the HLF group than in the NLF group (P < 0.0001; n = 11). CONCLUSIONS: The infiltration of M2 macrophages may be involved in HLF, while involvement of M1 macrophages may only occur early in inflammation. The expression of extracellular matrix proteins and macrophage-related factors was increased. Aging may also be associated with HLF.

miR-375 inhibits proliferation of mouse pancreatic progenitor cells by targeting YAP1.

BACKGROUND/AIMS: The Hippo signaling pathway regulates expansion and differentiation of stem cells and tissue progenitor cells during organ development and tissue regeneration. Previous studies have shown that YAP1, a potent effector of the Hippo signaling pathway, plays a crucial role in pancreas development, but the function of YAP1 in pancreatic progenitor cells is less known. METHODS: The spatio-temporal expression pattern of YAP1 in mouse developing pancreata was detected by in situ hybridization. The effect of silencing YAP1 on the proliferation of pancreatic progenitor cells was analyzed by CCK-8 assay and Ki67 immunostaining. The regulation of miR-375 on YAP1 expression was determined by dual luciferase reporter assay, QRT-PCR and western blot. Finally, the influence of miR-375 on proliferation of pancreatic progenitor cells was analyzed by CCK-8 assay and Ki67 immunostaining. RESULTS: We found that YAP1 was highly expressed in embryonic and adult pancreatic progenitor cells. Knocking down YAP1 by siRNA inhibited the proliferation of pancreatic progenitor cells. The mouse YAP1 was a target gene of miR-375, and miR-375 could target the 3' UTR of YAP1 mRNA to decrease its protein and mRNA levels. Similar to silencing YAP1 by siRNA, the proliferation of pancreatic progenitor cells was inhibited significantly by miR-375. CONCLUSION: Our results indicate that YAP1 is necessary for the proliferation of pancreatic progenitor cells and miR-375 participates in regulating YAP1 expression during pancreatic progenitor cells differentiation.

A clinical study of C arm-guided selective spinal nerve block combined with low-temperature plasma radiofrequency ablation of dorsal root ganglion in the treatment of zoster-related neuralgia.

Background: This study evaluated the analgesic efficacy and psychological response of low-temperature plasma ablation of dorsal root ganglion (DRG) combined with selective spinal nerve block in patients with acute or subacute zoster-related neuralgia (ZRN). Methods: Totally 90 ZRN patients were randomly and evenly divided into three groups. Treatment was given to Group A using C arm-guided selective spinal nerve block (C-SSVB), Group B using C-SSVB and pulsed radiofrequency (PRF), and Group C using C-SSVB and low-temperature plasma ablation of the DRG. The outcomes were examined using the Visual Analog Scale (VAS). Anxiety and depression of patients were evaluated using the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). Quality of life was assessed using the Pittsburgh Sleep Quality Index (PSQI) and postoperative Satisfaction scale. In addition, data on adverse events and medication usage rates were collected. Results: The 90 patients were eligible for this study. The three treatments reduced VAS scores with no significant difference between groups A and B at the same time points; however, group B tended to have numerically lower VAS scores. Comparatively, group C had significantly reduced VAS scores on day 1 and 1 month after treatment compared with the other two groups. In terms of the decreasing SAS, SDS and PSQI scores, all the three treatments improved the anxiety, depression and sleep quality of the patients. In addition, significant alleviation in anxiety was found in group C compared with group A at all- time points. However, there was no statistically significant difference among the three groups in treatment-related adverse events that mainly focused on puncture pain at the surgical-site, skin numbness and medication usage rates. Conclusions: C-SSVB and LTPRA of DRG will be considered as a promising treatment option for ZRN patients if those results can be confirmed after further validation.

Influence of macrophage polarization in herniated nucleus pulposus tissue on clinical efficacy after lumbar discectomy.

Background: Low back pain or sciatic pain because of lumbar intervertebral disc herniation (LDH) is caused by mechanical compression and/or an inflammatory component on the nerve root. However, it is difficult to define to what extent each component contributes to the pain. This study attempted to explore the effects of macrophage polarization on clinical symptoms in patients experiencing LDH after surgery, and investigated the association between macrophage cell percentages and clinical efficacy. Methods: This study retrospectively harvested nucleus pulposus (NP) tissue samples from 117 patients. Clinical symptoms and efficacy using the visual analog scale (VAS) and Oswestry Disability Index (ODI) were evaluated at different time points preoperatively and postoperatively. CD68, CCR7, CD163, and CD206 were selected as macrophage phenotypic markers. Results: Seventy-six samples showed positive expression of macrophage markers in NP samples of patients with LDH, whereas 41 patients displayed negative results. No significant differences were detected between the two groups, involvement of several demographic data, and preoperative clinical findings. With respect to the macrophage-positive group, no significant correlation was detected between the positive rate of the four markers and the VAS score or ODI after surgery. However, patients with NP samples positive for CD68 and CCR7 expression showed significantly lower VAS scores 1 week after surgery compared with those in the negative group. Moreover, the improvement in VAS score showed a strong positive correlation with CD68- and CCR7-positive cell percentages. Conclusions: Our results indicated that pro-inflammatory M1 macrophages may be associated with the reduction of chronic pain after surgery. Therefore, these findings contribute to better personalized pharmacological interventions for patients with LDH, considering the heterogeneity of pain.

Effectiveness of acupuncture therapy for postherpetic neuralgia: an umbrella review protocol.

INTRODUCTION: Several systematic reviews and meta-analysis indicate that acupuncture and related therapies may be a valuable adjunctive technique to pharmacological interventions for pain management of postherpetic neuralgia (PHN). However, the robustness of the results of these studies has not been evaluated. The aim of this proposed umbrella review is to provide more reliable evidence of the effectiveness of acupuncture therapy for PHN based on medical references for healthcare decision makers. METHODS AND ANALYSIS: PubMed, EMBASE, The Cochrane Library, Web of Science, Chinese BioMedical Literature Database, VIP Database for Chinese Technical Periodicals, China National Knowledge Infrastructure and Wan fang Database will be used to retrieve reviews. The time of publication will be limited from inception to March 2021. Two reviewers will screen all retrieved articles independently to identify their eligibility and extract the data. The quality will be assessed independently by two trained reviewers using Assessment of Multiple Systematic Reviews-2 for methodological quality, Risk of Bias in Systematic Review for level of bias, Preferred Reporting Items for Systematic Reviews and Meta-Analysis for reporting quality and Grading of Recommendations Assessment, Development and Evaluation for the quality of evidence. Any disagreements will be settled by discussion or the involvement of a third reviewer. ETHICS AND DISSEMINATION: The protocol of this review does not require ethical approval because the research will be based on publicly available data. The findings will be disseminated through publication in peer-reviewed international journals or presentation in academic conference. PROSPERO REGISTRATION NUMBER: CRD42020173341. REPORTING CHECKLIST: PRISMA-P, 2015.

[Therapeutic effect and mechanism of silver needle heat conduction therapy combined with loxoprofen sodium patch in patients with knee osteoarthritis].

OBJECTIVE: To observe the clinical efficacy of silver needle heat conduction therapy combined with loxoprofen sodium patch in the treatment of knee osteoarthritis (KOA). METHODS: A total of ninety-two patients with KOA were randomly and equally divided into loxoprofen sodium group and silver needle heat conduction therapy + loxoprofen sodium (combination) group, with 46 cases in each group. Patients of the combination group were treated with silver needle heat conduction therapy combined with loxoprofen sodium patch, while those of the loxoprofen sodium group were treated with loxoprofen sodium patch. The treatment was conducted for 4 weeks. The Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), bone metabolism index ï¼»including bone gla protein (BGP), bone-specific alkaline phosphatase (BALP), tartrate resistant acid phosphatase isomer (TRACP)-5bï¼½, and inflammation factors ï¼»including the tumor necrosis factor-α (TNF-α), transforming growth factor-ß (TGF-ß), interleukin-1ß (IL-1ß)ï¼½ were observed before and after treatment. The therapeutic effect was assessed after the treatment. RESULTS: After the treatment, the total scores of WOMAC, the levels of serum TRACP-5b, TNF-α and IL-1ß were significantly decreased (P<0.01), while the levels of serum BGP, BALP, and TGF-ß were significantly increased (P<0.01) in the two groups compared with their own pre-treatment. Silver needle plus loxoprofen sodium was more effective in reducing WOMAC score, TRACP-5b, TNF-α, IL-1ß level (P<0.01), and up-regulating BGP, BALP, and TGF-ß level (P<0.01) than loxoprofen. Of the 46 cases in the loxoprofen sodium and combination groups, 33 and 41 were effective, with the effective rate being 71.7% and 89.1%, respectively. The comprehensive therapeutic effect of the combination group was significantly superior to that of the loxoprofen group (P<0.05). CONCLUSION: Silver needle heat conduction therapy combined with loxoprofen sodium can effectively treat KOA, its mechanism may be related to alleviating inflammation and improving bone metabolism.

[The roles of miR-17-92 cluster in mammal development and tumorigenesis].

MicroRNAs (miRNAs) are a new class of small, non-coding RNAs that regulate gene expression. The base pairing interactions between miRNAs and their target mRNAs, often within the 3'-untranslated region (UTR) of target genes, result in the degradation of target mRNAs or repression of their translation. MiRNAs regulate a diverse range of physiological processes, including cell differentiation and proliferation, mammalian development and human disease. Many studies have shown that miR-17-92 cluster, which encodes miR-17-5p, miR-17-3p, miR-18a, miR-19a, miR-20a, miR-19b-1, and miR-92-1, is expressed in many mammalian tissues. This cluster contributes to the development of heart, lung, blood vessel, and immune system. In addition, it can induce tumorigenesis, such as lymphoma and vascularized tumor as an oncogene. However, miR-17-92 cluster proved to suppress breast cancer cell proliferation and tumor colony formation as a tumor suppressor. This paper reviews the roles of miR-17-92 cluster in mammal development and the relationship between miR-17-92 cluster and tumorigenesis.

Complete disassociation of adult pancreas into viable single cells through cold trypsin-EDTA digestion.

The in vitro isolation and analysis of pancreatic stem/progenitor cells are necessary for understanding their properties and function; however, the preparation of high-quality single-cell suspensions from adult pancreas is prerequisite. In this study, we applied a cold trypsin-ethylenediaminetetraacetic acid (EDTA) digestion method to disassociate adult mouse pancreata into single cells. The yield of single cells and the viability of the harvested cells were much higher than those obtained via the two commonly used warm digestion methods. Flow cytometric analysis showed that the ratio of ductal or BCRP1-positive cells in cell suspensions prepared through cold digestion was consistent with that found in vivo. Cell culture tests showed that pancreatic epithelial cells prepared by cold digestion maintained proliferative capacity comparable to those derived from warm collagenase digestion. These results indicate that cold trypsin-EDTA digestion can effectively disassociate an adult mouse pancreas into viable single cells with minimal cell loss, and can be used for the isolation and analysis of pancreatic stem/progenitor cells.

MiR-18a regulates expression of the pancreatic transcription factor Ptf1a in pancreatic progenitor and acinar cells.

The basic helix-loop-helix (bHLH) transcription factor Ptf1a plays stage-specific roles in the developing pancreas. During early pancreatic development, low levels of Ptf1a preferentially promote the differentiation of pancreatic progenitor cells into endocrine cells, whereas high levels of Ptf1a shift pancreatic progenitors towards an exocrine cell fate. In adults, Ptf1a is essential for the production of exocrine enzymes by pancreatic acinar cells. In this paper, we show that Ptf1a expression is repressed by miR-18a in pancreatic progenitors and acinar cells via its binding to the 3'UTR of Ptf1a mRNA. Furthermore, overexpression of miR-18a exerts little effect on pancreatic progenitors and acinar cells. These results indicate that miR-18a plays a fine-tuning role in regulating pancreatic progenitors and exocrine cells through the repression of Ptf1a expression.

MicroRNA-19b downregulates insulin 1 through targeting transcription factor NeuroD1.

MiR-17-92 cluster miRNAs are disclosed to contribute to the development of multiple organs and tumorigenesis, but their roles in pancreas development remains unclear. In this study, we found that miR-19b, a member of miR-17-92, was highly expressed in the pancreatic progenitor cells, and miR-19b could target the 3' UTR of NeuroD1 mRNA to decrease its protein and mRNA levels. Functional analysis showed that miR-19b exerted little effect on the proliferation of pancreatic progenitors, whereas it inhibited the expression of insulin 1, but not insulin 2 in MIN6 cells. These results suggest that miR-19b can downregulate insulin 1 expression through targeting transcription factor NeuroD1, and thus regulate the differentiation and function of ß-cells.