Effects of unfractionated heparin and rivaroxaban on the expression of heparanase and fibroblast growth factor 2 in human osteoblasts

Enoxaparin and Early Postoperative Tibial Nailing: Increased Nonunion Revision Rates

OBJECTIVES

To determine the association between postoperative enoxaparin use and the risk of requiring surgery for nonunion in patients treated with intramedullary nailing for midshaft fractures of the tibia.

METHODS

DESIGN

Retrospective cohort analysis.

SETTING

Data were sourced from the PearlDiver national database.

PATIENT SELECTION CRITERIA

Patients were identified through the PearlDiver database by using Current Procedural Terminology and International Classification of Diseases (ICD-10) codes. Included patients had undergone intramedullary nailing for midshaft fractures of the tibia between 2015 and 2020 and subsequently underwent revision surgery due to nonunion.

OUTCOME MEASURES AND COMPARISONS

The primary outcome measured in this study was the rate of nonunion following intramedullary nailing for the different types of tibial shaft fractures (closed, Type I/II open, Type III open). For each fracture subtype, the study compared nonunion rates between those who received enoxaparin in the postoperative period and those who did not receive enoxaparin at any time during the first 6 weeks postoperatively. Factors such as the timing and duration of enoxaparin therapy and demographic variables were also considered.

RESULTS

The study included 16,986 patients, average age was 49.2 years (SD 17.3); 43.1% were female. Five hundred four patients required revision surgery for nonunion (3.4%). Among patients who did not receive enoxaparin, the nonunion rates were 1.6%, 3.9%, and 6.9% for closed, Type I/II open, and Type III open fractures, respectively. For patients who received enoxaparin within the first 2 weeks, the nonunion rates were 2.6%, 4.7%, and 7.9% for closed (RR = 1.67, P < 0.0001), Type I/II open (RR = 1.21, P < 0.0001), and Type III open (RR = 1.17, P = 0.355) fractures, respectively. Logistic regression confirmed enoxaparin was independently associated with nonunion (odds ratios [OR] = 1.75, P = 0.0013 for closed fractures; OR = 1.51, P = 0.034 for Type I/II open fractures). Tobacco use was also a contributing factor (OR = 2.43, P < 0.0001 for closed fractures; OR = 2.00, P < 0.0001 for Type I/II open fractures; OR = 2.04, P = 0.0008 for Type III open fractures).

CONCLUSIONS

The postoperative use of enoxaparin was associated with an elevated risk of nonunion in patients treated with intramedullary nailing for fractures of the tibial shaft.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

NF-kB affects migration of vascular smooth muscle cells after treatment with heparin and ibrutinib

The migration of vascular smooth muscle cells (VSMCs) is one of the most important events in the remodeling of atherosclerosis plaque. The aim of study was to investigate the role of Heparin in the VSMC migration and its association with the NF-kB, collagen 1 and collagen 3 expression levels. Moreover, the incorporation of Heparin was studied in the VSMC cultures including Betulinic acid and Ibrutinib. Twelve cell groups were cultured and treated with the Heparin, Betulinic acid and Ibrutinib based on the viability and toxicity in 24-h and 48-h periods. The gene and protein expression levels were measured by RT-qPCR and western blotting techniques. The VSMC migration was determined by scratch test. In contrast with Ibrutinib (2 μM), Heparin (30 IU) increased significantly (P < 0.05) the NF-kB gene and protein expression levels and the VSMC migration during the exposure periods. Heparin (15 IU and 30 IU) also increased the collagen 1 gene expression level in the 48-h period while Heparin (5 IU and 15 IU) increased the collagen 3 gene expression levels in both periods. Incorporating Heparin into the cultures including Betulinic acid and Ibrutinib affected the collagen 1 and collagen 3 expression levels. The data suggested that the cell migration relates to NF-kB in the VSMCs treated with Heparin and Ibrutinib. Furthermore, the Heparin doses (5 IU and 15 IU) were safe for VSMCs based on the NF-kB, and collagen 3 expression levels.

Lipid and Bone Effects of Heparin Use During Hemodialysis

Unfractionated heparin (UFH) and low-molecular-weight heparins (LMWHs) are commonly prescribed anticoagulants for chronic hemodialysis (HD). The dialysis population comprises a unique group that receives heparin three times per week for a long period, with potential long-term cumulative metabolic effects such as osteoporosis and worsening lipid profile. HD patients have approximately half the number of lipases as healthy individuals, and their lipid metabolism is limited because of this decrease as well as partially inhibited function. Administration of UFH or LMWHs for anticoagulation can lead to metabolic starvation despite high triglyceride levels at the end of HD. In vitro studies indicate that UFH and LMWHs inhibit osteoblasts and promote osteoclasts. In patients on HD, long-term use of UFH or LMWHs did not worsen chronic kidney disease-mineral bone disease. Further investigation is needed to elucidate the underlining mechanisms of UFH and LMWHs and their possible influences on maintenance HD patients.

Hirudin promotes proliferation and osteogenic differentiation of HBMSCs via activation of cyclic guanosine monophosphate (cGMP)/protein kinase-G (PKG) signaling pathway

Osteoporosis is a public health problem resulting in higher susceptibility to bone fracture. Hirudin is known as a direct thrombin inhibitor, which is isolated from the salivary gland of the medicinal leech. This present study aimed to evaluate the effect of Hirudin on the proliferation and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (HBMSCs). In our study, the effect of Hirudin on the proliferation of HBMSCs was evaluated with the CCK-8 and MTT assays. The capacity of osteogenic differentiation and mineralization of HBMSCs were evaluated with ALP and alizarin red staining, respectively. cGMP content was determined by ELISA. Western blotting and qRT-PCR were used to investigate the effect of Hirudin on the expression of osteoblast-specific markers, including Runx2, osterix (OSX), osteocalcin (OCN), collagen1 (Col1). In our study, Hirudin treatment promoted cell viability. Moreover, Hirudin treatment increased ALP activity of HBMSCs and red coloration of alizarin. Interestingly, cGMP inhibitor partly reversed the effect of Hirudin on the proliferation, differentiation and mineralization of HBMSCs. In conclusion, Hirudin promoted the proliferation, differentiation and mineralization of HBMSCs via activation of cGMP signaling pathway. Hence, Hirudin contributed to bone remodeling and might represent as an effective agent for the treatment of osteoporosis.

The Heparanase Regulatory Network in Health and Disease

The extracellular matrix (ECM) is a structural framework that has many important physiological functions which include maintaining tissue structure and integrity, serving as a barrier to invading pathogens, and acting as a reservoir for bioactive molecules. This cellular scaffold is made up of various types of macromolecules including heparan sulfate proteoglycans (HSPGs). HSPGs comprise a protein core linked to the complex glycosaminoglycan heparan sulfate (HS), the remodeling of which is important for many physiological processes such as wound healing as well as pathological processes including cancer metastasis. Turnover of HS is tightly regulated by a single enzyme capable of cleaving HS side chains: heparanase. Heparanase upregulation has been identified in many inflammatory diseases including atherosclerosis, fibrosis, and cancer, where it has been shown to play multiple roles in processes such as epithelial-mesenchymal transition, angiogenesis, and cancer metastasis. Heparanase expression and activity are tightly regulated. Understanding the regulation of heparanase and its downstream targets is attractive for the development of treatments for these diseases. This review provides a comprehensive overview of the regulators of heparanase as well as the enzyme's downstream gene and protein targets, and implications for the development of new therapeutic strategies.

Lactobacillus Plantarum HFY15 Helps Prevent Retinoic Acid-Induced Secondary Osteoporosis in Wistar Rats

A rat model of secondary osteoporosis was constructed using retinoic acid as an inducer, and the genes, proteins, and bone mass of the rats were analyzed. qPCR detection of the Wnt/β-catenin and OPG/RANK/RANKL signaling pathway-related gene expression levels showed that Lactobacillus plantarum HFY15 played a positive role in regulating both pathways. HFY15 significantly increased β-catenin, Lrp5, Lrp6, Wnt10b, OPG, RANKL, and Runx2 expression and downregulated DKK1, RANK, CTSK, TRACP, and ALP expression. Enzyme-linked immunosorbent assays further confirmed the qPCR results. Tartrate-resistant acid phosphatase staining showed that HFY15 slowed retinoic acid-induced osteoclast formation. Microcomputed tomography showed that HFY15 reduced trabecular separation and increased the percent bone volume, trabecular numbers, trabecular thickness, and bone mineral density in the rats in vivo. These findings indicate that HFY15 may help prevent retinoic acid-induced secondary osteoporosis in vivo.

Rehabilitation pharmacotherapy: A scoping review

Many patients in rehabilitation facilities are affected by polypharmacy. Polypharmacy is associated with rehabilitation outcomes and functional recovery. Consequently, a combination of rehabilitation and pharmacotherapy may improve the outcomes of older people undergoing rehabilitation. A recent report described the concept of rehabilitation pharmacotherapy. The concept envisages helping frail older people and people with disabilities to achieve the highest possible body function, activity level and quality of life. There are two key tenets of rehabilitation pharmacotherapy: "pharmacotherapy in consideration of rehabilitation" and "rehabilitation in consideration of pharmacotherapy." "Pharmacotherapy in consideration of rehabilitation" includes use of drugs to treat impairment, activity limitation and participation restriction based on the International Classification of Functioning, Disability, and Health. "Rehabilitation in consideration of pharmacotherapy" refers to tailoring of rehabilitation considering the content of pharmacotherapy. With respect to drugs and motor dysfunction, anticholinergic drugs are associated with dysphagia and fractures. Increased use of potentially inappropriate medications may adversely affect the nutritional status. With respect to activities of daily living, polypharmacy and use of potentially inappropriate medications negatively affect the improvement in motor function during rehabilitation. Potent anticholinergic drugs are more likely to impede the improvement in cognitive function. In this review, we address the concept of rehabilitation pharmacotherapy and discuss its importance from the perspective of polypharmacy, the effect of drugs on disability and disease, nutritional status and activities of daily living. Geriatr Gerontol Int 2020; 20: -.

The Role of Mast Cells in Bone Metabolism and Bone Disorders

Mast cells (MCs) are important sensor and effector cells of the immune system that are involved in many physiological and pathological conditions. Increasing evidence suggests that they also play an important role in bone metabolism and bone disorders. MCs are located in the bone marrow and secrete a wide spectrum of mediators, which can be rapidly released upon activation of mature MCs following their differentiation in mucosal or connective tissues. Many of these mediators can exert osteocatabolic effects by promoting osteoclast formation [e.g., histamine, tumor necrosis factor (TNF), interleukin-6 (IL-6)] and/or by inhibiting osteoblast activity (e.g., IL-1, TNF). By contrast, MCs could potentially act in an osteoprotective manner by stimulating osteoblasts (e.g., transforming growth factor-β) or reducing osteoclastogenesis (e.g., IL-12, interferon-γ). Experimental studies investigating MC functions in physiological bone turnover using MC-deficient mouse lines give contradictory results, reporting delayed or increased bone turnover or no influence depending on the mouse model used. By contrast, the involvement of MCs in various pathological conditions affecting bone is evident. MCs may contribute to the pathogenesis of primary and secondary osteoporosis as well as inflammatory disorders, including rheumatoid arthritis and osteoarthritis, because increased numbers of MCs were found in patients suffering from these diseases. The clinical observations could be largely confirmed in experimental studies using MC-deficient mouse models, which also provide mechanistic insights. MCs also regulate bone healing after fracture by influencing the inflammatory response toward the fracture, vascularization, bone formation, and callus remodeling by osteoclasts. This review summarizes the current view and understanding of the role of MCs on bone in both physiological and pathological conditions.

Kaempferol targeting on the fibroblast growth factor receptor 3-ribosomal S6 kinase 2 signaling axis prevents the development of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic inflammatory disease that mainly affects the synovial joints. Although involvement of the fibroblast growth factor (FGF) signaling pathway has been suggested as an important modulator in RA development, no clear evidence has been provided. In this study, we found that synovial fluid basic FGF (bFGF) concentration was significantly higher in RA than in osteoarthritis (OA) patients. bFGF stimulates proliferation and migration of human fibroblast-like synoviocytes (FLSs) by activation of the bFGF-FGF receptor 3 (FGFR3)-ribosomal S6 kinase 2 (RSK2) signaling axis. Moreover, a molecular docking study revealed that kaempferol inhibited FGFR3 activity by binding to the active pocket of the FGFR3 kinase domain. Kaempferol forms hydrogen bonds with the FGFR3 backbone oxygen of Glu555 and Ala558 and the side chain of Lys508. Notably, the inhibition of bFGF-FGFR3-RSK2 signaling by kaempferol suppresses the proliferation and migration of RA FLSs and the release of activated T-cell-mediated inflammatory cytokines, such as IL-17, IL-21, and TNF-α. We further found that activated phospho-FGFR3 and -RSK2 were more highly observed in RA than in OA synovium. The hyperplastic lining and sublining lymphoid aggregate layers of RA synovium showed p-RSK2-expressing CD68⁺ macrophages with high frequency, while pRSK2-expressing CD4⁺ T-cells was observed at a lower frequency. Notably, kaempferol administration in collagen-induced arthritis mice relieved the frequency and severity of arthritis. Kaempferol reduced osteoclast differentiation in vitro and in vivo relative to the controls and was associated with the inhibition of osteoclast markers, such as tartrate-resistant acid phosphatase, integrin β3, and MMP9. Conclusively, our data suggest that bFGF-induced FGFR3-RSK2 signaling may play a critical role during the initiation and progression of RA in terms of FLS proliferation and enhanced osteoclastogenesis, and that kaempferol may be effective as a new treatment for RA.