Mutations in COMP cause familial carpal tunnel syndrome

Hepatoprotective Activity of Nature-Derived Polyphenols Studied by Mass Spectrometry Based Multi-OMICS Approach

The aim of this study was to examine the hepatoprotective activity of multicomponent mixtures of natural origin in the BALB/C mouse model, with subacute liver failure (SALF) induced by the administration of toxin carbon tetrachloride (CCl4). The hepatoprotective activity of activated hydrolytic lignin (BP-Cx-1), humic acid peloids (HA), and isoflavones from kudzu Pueraria lobata roots (IFL) was evaluated using mass spectrometry (MS)-based omics technologies. Our MS-based approach revealed new insights into the molecular mechanisms of the hepatoprotective activity of multicomponent mixtures of natural origin. Significant differences were observed in the proteome and metabolome profiles of the urine and liver of BALB/c mice with SALF between a control group with CCl4 administration, intact controls, and groups receiving potential hepatoprotectors of natural origin (BP-Cx-1, HA, IFL). Proteomic and metabolomics analyses demonstrated that among the hepatoprotectors, IFL possessed the highest hepatoprotective potential, which correlated well with the relative effectiveness of the drugs recorded during in vitro studies. These results correlate with the relative effectiveness of the drugs recorded in previous in vitro and in vivo studies. The leading IFL activity may be attributed to a higher content of active polyphenolic components compared to heterogeneous HA and BP-Cx-1. Enrichment with active components by fractionation is a direction that can be explored for developing hepatoprotective agents based on natural complex polyphenols.

Maladaptive Peripheral Ketogenesis in Schwann Cells Mediated by CB1R Contributes to Diabetic Neuropathy

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes. Although studies have previously investigated metabolic disruptions in the peripheral nervous system (PNS), the exact metabolic mechanisms underlying DPN remain largely unknown. Herein, a specific form of metabolic remodeling involving aberrant ketogenesis within Schwann cells (SCs) in streptozotocin (STZ)-induced type I diabetes mellitus is identified. The PNS adapts poorly to such aberrant ketogenesis, resulting in disrupted energy metabolism, mitochondrial damage, and homeostatic decompensation, ultimately contributing to DPN. Additionally, the maladaptive peripheral ketogenesis is highly dependent on the cannabinoid type-1 receptor (CB1R)-Hmgcs2 axis. Silencing CB1R reprogrammed the metabolism of SCs by blocking maladaptive ketogenesis, resulting in rebalanced energy metabolism, reduced histopathological changes, and improved neuropathic symptoms. Moreover, this metabolic reprogramming can be induced pharmacologically using JD5037, a peripheral CB1R blocker. These findings revealed a new metabolic mechanism underlying DPN, and promoted CB1R as a promising therapeutic target for DPN.

Establishment of a Magnetically Controlled Scalable Nerve Injury Model

Animal models of peripheral nerve injury (PNI) serve as the fundamental basis for the investigations of nerve injury, regeneration, and neuropathic pain. The injury properties of such models, including the intensity and duration, significantly influence the subsequent pathological changes, pain development, and therapeutic efficacy. However, precise control over the intensity and duration of nerve injury remains challenging within existing animal models, thereby impeding accurate and comparative assessments of relevant cases. Here, a new model that provides quantitative and off-body controllable injury properties via a magnetically controlled clamp, is presented. The clamp can be implanted onto the rat sciatic nerve and exert varying degrees of compression under the control of an external magnetic field. It is demonstrated that this model can accurately simulate various degrees of pathology of human patients by adjusting the magnetic control and reveal specific pathological changes resulting from intensity heterogeneity that are challenging to detect previously. The controllability and quantifiability of this model may significantly reduce the uncertainty of central response and inter-experimenter variability, facilitating precise investigations into nerve injury, regeneration, and pain mechanisms.

Thrombospondins: Conserved mediators and modulators of metazoan extracellular matrix

This review provides a personal overview of significant scientific developments in the thrombospondin field during the course of my career. Thrombospondins are multidomain, multimeric, calcium-binding extracellular glycoproteins with context-specific roles in tissue organisation. They act at cell surfaces and within ECM to regulate cell phenotype and signalling, differentiation and assembly of collagenous ECM, along with tissue-specific roles in cartilage, angiogenesis and synaptic function. More recently, intracellular, homeostatic roles have also been identified. Resolution of structures for the major domains of mammalian thrombospondins has facilitated major advances in understanding thrombospondin biology from molecule to tissue; for example, in illuminating molecular consequences of disease-causing coding mutations in human pseudoachrondroplasia. Although principally studied in vertebrates, thrombospondins are amongst the most ancient of animal ECM proteins, with many invertebrates encoding a single thrombospondin and the thrombospondin gene family of vertebrates originating through gene duplications. Moreover, thrombospondins form one branch of a thrombospondin superfamily that debuted at the origin of metazoans. The super-family includes additional sub-groups, present only in invertebrates, that differ in N-terminal domain organisation, share the distinctive TSP C-terminal region domain architecture and, to the limited extent studied to date, apparently contribute to tissue development and organisation. Finally, major lines of translational research are discussed, related to fibrosis; TSP1, TSP2 and inhibition of angiogenesis; and the alleviation of chronic cartilage tissue pathologies in pseudoachrondroplasia.

Inherited Variants in the COL11A, COL1A, COL5A1, COMP, GSTM1 Genes and the Risk of Carpal Tunnel Syndrome

The pathogenesis of most cases of carpal tunnel syndrome is not clearly defined. There are some aspects of the disease that suggest a potential effect of genetic predispositions. Mutations (variants) within the genes encoding various subtypes of collagen synthesis, oligomerisation in the endoplasmic reticulum and inactivation of reactive oxygen species may be involved in the development of carpal tunnel syndrome. The objective of this study was to determine the role of DNA alterations within the COL11A, COL1A, COL5A1, COMP and GSTM1 genes in the pathogenesis of carpal tunnel syndrome based on a Polish population.

STUDY DESIGN

In the discovery phase, a total of 96 patients with familial aggregation of CTS were genotyped using a Next Generation Sequencing panel in order to find possible mutations within the studied genes. The potential pathogenicity of the detected variants was investigated using the predictions of several in-silico algorithms and the TaqMan technology. In the association phase of the study, a group of 345 CTS patients and 1035 healthy controls were genotyped.

RESULTS

A total of 35 splice-site or exonic non-synonymous variants were detected by NGS. We did not identify any clearly pathogenic or likely pathogenic alternations. The 30 variants were identified as benign or likely benign. Five missense changes were predicted as VUS and selected for association study. The COL5A1 c.1595 C>T (p.Ala532Val) was detected in one out of 345 cases and three out of 1035 controls (P=1, OR=1); this indicates that the variant is a neutral alteration. Four remaining variants - c.2840 C>A, c.5395 G>A, c.1331 C>G, c.1590 C>A - were present in none out of the 345 CTS patients and none out of 1035 controls.

CONCLUSION

The main finding of this study was that there was no independent association between the variants of five examined genes and carpal tunnel syndrome. Four uncertain variants were identified that seem to be extremely rare in the Polish population.

COMP promotes pancreatic fibrosis by activating pancreatic stellate cells through CD36-ERK/AKT signaling pathways

BACKGROUND

Pancreatic fibrosis is one of the most important pathological features of chronic pancreatitis (CP) and pancreatic stellate cells (PSCs) are the key cells of fibrosis. As an extracellular matrix (ECM) glycoprotein, cartilage oligomeric matrix protein (COMP) is critical for collagen assembly and ECM stability and recent studies showed that COMP exert promoting fibrosis effect in the skin, lungs and liver. However, the role of COMP in activation of PSCs and pancreatic fibrosis remain unclear. We aimed to investigate the role and specific mechanisms of COMP in regulating the profibrotic phenotype of PSCs and pancreatic fibrosis.

METHODS

ELISA method was used to determine serum COMP in patients with CP. Mice model of CP was established by repeated intraperitoneal injection of cerulein and pancreatic fibrosis was evaluated by Hematoxylin-Eosin staining (H&E) and Sirius red staining. Immunohistochemical staining was used to detect the expression changes of COMP and fibrosis marker such as α-SMA and Fibronectin in pancreatic tissue of mice. Cell Counting Kit-8, Wound Healing and Transwell assessed the proliferation and migration of human pancreatic stellate cells (HPSCs). Western blotting, qRT-PCR and immunofluorescence staining were performed to detect the expression of fibrosis marker, AKT and MAPK family proteins in HPSCs. RNA-seq omics analysis as well as small interfering RNA of COMP, recombinant human COMP (rCOMP), MEK inhibitors and PI3K inhibitors were used to study the effect and mechanism of COMP on activation of HPSCs.

RESULTS

ELISA showed that the expression of COMP significantly increased in the serum of CP patients. H&E and Sirius red staining analysis showed that there was a large amount of collagen deposition in the mice in the CP model group and high expression of COMP, α-SMA, Fibronectin and Vimentin were observed in fibrotic tissues. TGF-β1 stimulates the activation of HPSCs and increases the expression of COMP. Knockdown of COMP inhibited proliferation and migration of HPSCs. Further, RNA-seq omics analysis and validation experiments in vitro showed that rCOMP could significantly promote the proliferation and activation of HPSCs, which may be due to promoting the phosphorylation of ERK and AKT through membrane protein receptor CD36. rCOMP simultaneously increased the expression of α-SMA, Fibronectin and Collagen I in HPSCs.

CONCLUSION

In conclusion, this study showed that COMP was up-regulated in CP fibrotic tissues and COMP induced the activation, proliferation and migration of PSCs through the CD36-ERK/AKT signaling pathway. COMP may be a potential therapeutic candidate for the treatment of CP. Interfering with the expression of COMP or the communication between COMP and CD36 on PSCs may be the next direction for therapeutic research.

Carpal tunnel syndrome

Median neuropathy at the wrist, commonly referred to as carpal tunnel syndrome (CTS), is the most common entrapment neuropathy. It is caused by chronic compression of the median nerve at the wrist within the space-limited carpal tunnel. Risk factors that contribute to the etiology of compression include female gender, obesity, work-related factors, and underlying medical conditions, such as hypothyroidism, pregnancy, and amyloidosis. The diagnosis is made on clinical grounds, although these can be confounded by anatomical variations. Electrodiagnostic studies, which are specific and sensitive in diagnosing CTS, support the diagnosis; however, a subgroup may present with normal results. The advent of imaging techniques, including ultrasound and MRI, further assists the diagnostic process. The management of CTS is divided into the nonsurgical approaches that include hand therapy, splinting and corticosteroid injection, and surgical decompression of the carpal tunnel. Although several surgical techniques have been developed, no one method is more effective than the other. Each of these management approaches are effective at providing symptom relief and are utilized at different severities of the condition. There is, however, a lack of consensus on standardized diagnostic criteria, as well as when and to whom to refer patients for surgery.

A comparative study on efficacy of modified endoscopic minimally invasive treatment and traditional open surgery for primary carpal tunnel syndrome

BACKGROUND AND OBJECTIVE

Carpal tunnel syndrome (CTS) is the most common type of median nerve entrapment neuropathy. This study aims to comparatively assess the effectiveness and clinical efficacy of modified transforaminal endoscopic minimally invasive incision of transverse carpal ligament against traditional open incision of transverse carpal ligament in the treatment of CTS.

METHOD

The clinical data of 35 patients (57 wrists) with primary CTS treated in Shanxi Bethune Hospital, China, were retrospectively analyzed. The patients were divided into observation group (21 cases, 33 wrists) and control group (14 cases, 24 wrists), respectively, who underwent modified endoscopic minimally invasive incision of transverse carpal ligament and traditional open incision of transverse carpal ligament release. The Boston Carpal Tunnel Questionnaire (BCTQ) was assessed at for points: before the operation; 2 weeks; 1 month; and 3 months after operation. The BCTQ scores of the two groups were compared on all four points. The incidence of intraoperative and postoperative complication was used as the evaluation index. The study variables were comparatively assessed before and postoperation and also between the groups.

RESULTS

The BCTQ scores at 2 weeks, 1 month and 3 months after the operation were significantly lower than preoperative BCTQ scores (P < 0.005) for both the groups. There was no significant difference in BCTQ scores between the two groups at the four assessment points (P > 0.005). The scar size and wound healing time were significantly better with modified transforaminal endoscopic minimally invasive transverse carpal ligament incision.

CONCLUSION

The clinical effects of both modified transforaminal minimally invasive incision of transverse carpal ligament and traditional open incision of transverse carpal ligament are significant, while the treatment efficacy of modified transforaminal minimally invasive transverse carpal ligament incision is better in terms of operation time, wound size, postoperative scar size and incision healing time.

A literature review of carpal tunnel syndrome and its association with body mass index, wrist ratio, wrist to palm ratio, and shape index

STUDY DESIGN

Systematic literature review of case-controlled studies.

INTRODUCTION

Carpal tunnel syndrome (CTS) is one of the most common tubular neuropathies where certain anatomical variations may be accounted for as risk factors for CTS, including body mass index (BMI), wrist ratio (WR), wrist to palm ratio (WPR), shape index (SI), and digit length.

PURPOSE OF THE STUDY

To assess case-control studies examining the association between specific anatomical variations of the wrist as risk factors for developing CTS and whether this effect is the same for both genders.

METHODS

The literature search was conducted between February-June 2020 through PubMed, Cochrane Library, CINAHL Plus and PEDro. The literature search yielded 149 potential publications, fifteen of which were filtered in accordance with eligibility criteria. The methodological quality was assessed by using the Newcastle-Ottawa Quality Assessment Form for Case-Control Studies (NOS).

RESULTS

The total number of subjects included in this review was n=4299. The largest sample was n=1117 participants and the smallest n=54. All studies included patients who had a clinical diagnosis of CTS confirmed with nerve conduction studies and or ultrasonography. CTS was significantly higher in patients with higher BMI, WR, WPR compared to control groups. BMI and WR were the only indicators that can be considered as strong risk factors.

CONCLUSIONS

Discussion: Despite the general patterns on the association of BMI, WPR, WR and SI as risk factors for the development of CTS, there were exceptions to the accepted results and conclusions.

CONCLUSION

Clinicians are recommended to conduct more research to confirm anthropometric measurements as risk factors for the development of CTS, mainly SI and WPR. When determining the cut-off values for BMI and WR, it is recommended to take into account additional risk factors such as occupation.

Identification of Copy Number Variants in a Southern Chinese Cohort of Patients with Congenital Scoliosis

Congenital scoliosis (CS) is a lateral curvature of the spine resulting from congenital vertebral malformations (CVMs) and affects 0.5–1/1000 live births. The copy number variant (CNV) at chromosome 16p11.2 has been implicated in CVMs and recent studies identified a compound heterozygosity of 16p11.2 microdeletion and TBX6 variant/haplotype causing CS in multiple cohorts, which explains about 5–10% of the affected cases. Here, we studied the genetic etiology of CS by analyzing CNVs in a cohort of 67 patients with congenital hemivertebrae and 125 family controls. We employed both candidate gene and family-based approaches to filter CNVs called from whole exome sequencing data. This identified 12 CNVs in four scoliosis-associated genes (TBX6, NOTCH2, DSCAM, and SNTG1) as well as eight recessive and 64 novel rare CNVs in 15 additional genes. Some candidates, such as DHX40, NBPF20, RASA2, and MYSM1, have been found to be associated with syndromes with scoliosis or implicated in bone/spine development. In particular, the MYSM1 mutant mouse showed spinal deformities. Our findings suggest that, in addition to the 16p11.2 microdeletion, other CNVs are potentially important in predisposing to CS.

Transcriptional changes of mouse ovary during follicle initial or cyclic recruitment mediated by extra hormone treatment

AIMS

Folliculogenesis contains gonadotropin-independent and -dependent stage. Disruption in any of this process would induce failure in retrieving capable oocytes during clinical treatment. However, there is still limited understanding of the molecular components specifically regulating this process.

MATERIAL AND METHODS

Ovaries of P3, P20 and exogenous gonadotropin-treated P22 mice were sampled and underwent RNA-seq to investigate the transcriptome variance during mouse folliculogenesis.

KEY FINDINGS

In our dataset, 1883 and 626 DEGs were captured for each stage respectively, which were further clustered into eight expression patterns. Pathway enrichment analysis identified distinct biological processes enriched in two stages, with the most prominent being the pathways related to metabolism, gene expression, cell cycle, immune system and DNA methylation. Transcriptional regulator inference yielded eight master transcription factors (i.e. Runx1, Stat3, Sox3, Pou5f1, Gata4, Foxl2, Cebpb, and Esr1) driving folliculogenesis.

SIGNIFICANCE

Our study revealed the temporal transcriptional reprogramming and gene expression dynamics during folliculogenesis mediated by extra hormone treatment, which could provide novel insights to controlled ovarian stimulation in future infertility treatment.