Effects of antithrombotic drugs fondaparinux and tinzaparin on in vitro proliferation and osteogenic and chondrogenic differentiation of bone-derived mesenchymal stem cells

The effect of drugs on implant osseointegration- A narrative review

OBJECTIVE

This narrative review aims to investigate the effects of drugs on implant osseointegration, analyzing their potential positive or negative impact on the direct structural and functional connection between bone and load-carrying implants.

BACKGROUND

The review seeks to provide a comprehensive understanding of osseointegration, which refers to the successful integration of an implant with living bone, resulting in no progressive relative movement between them. Exploring the effects of drugs on implant osseointegration is crucial for optimizing outcomes and enhancing patient care in orthopedic implant procedures.

METHODS

Relevant studies on the effects of drugs on implant osseointegration were identified through a literature search. Electronic databases, including PubMed, Embase, and Google Scholar, were utilized, employing appropriate keywords and MeSH terms related to osseointegration, implants, and drug interventions. The search was limited to English studies.

DISCUSSION

This overview presents a detailed analysis of the effects of drugs on implant osseointegration. It explores drugs such as bisphosphonates, teriparatide, statins, angiotensin-converting enzyme inhibitors, beta-blockers, nitrites, and thiazide diuretics as promoters of osseointegration. Conversely, loop diuretics, non-steroidal anti-inflammatory drugs, corticosteroids, cyclosporine A, cisplatin, methotrexate, antibiotics, proton pump inhibitors (PPIs), antiepileptics, selective serotonin reuptake inhibitors (SSRIs), and anticoagulants are discussed as inhibitors of the process. The role of vitamin D3 remains uncertain. The complex relationship between drugs and the biology of implant osseointegration is emphasized, underscoring the need for further in vitro and in vivo studies to validate their effects CONCLUSION: This narrative review contributes to the literature by providing an overview of the effects of drugs on implant osseointegration. It highlights the complexity of the subject and emphasizes the necessity for more extensive and sophisticated studies in the future. Based on the synthesis of the reviewed literature, certain drugs, such as bisphosphonates and teriparatide, show potential for promoting implant osseointegration, while others, including loop diuretics and certain antibiotics, may impede the process. However, additional research is required to solidify these conclusions and effectively inform clinical practice.

Phytochemical analysis and thrombolytic profiling of Costus afer stem fractions

Background

The most commonly occurring mechanism driving ischemic heart disease, ischemic stroke, and myocardial infarction is thrombosis. It is normally characterized by platelet activation and aggregation. Thrombolytics have been used in the treatment of several forms of thrombosis, but their adverse effects have limited their usefulness. Thus, there is a need to develop alternatives from medicinal plants known to possess antithrombotic activity such as Costus afer.

Results

The phytochemical evaluations indicated the presence of flavonoids, alkaloids, cardiac glycosides, tannins, terpenoids, and saponins. The antithrombotic profiling showed that streptokinase had the highest percentage clot lysis, followed by ethylacetate fraction of the extract, which was higher than aspirin and other fractions of the extract.

Conclusion

The present findings show that C. afer stem extract and various fractions possess antithrombotic activities. However, further studies are needed to characterize the antithrombotic bioactive compounds present in the different fractions that are responsible for the activities.

Effects of Anticoagulant Medication on Bone-Healing

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A substantial proportion of patients undergoing orthopaedic care are prescribed some form of anticoagulant medication, whether for perioperative venous thromboembolism prophylaxis or chronic anticoagulation in the setting of a cardiac or other condition.

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An abundance of preclinical data suggests that many commonly used anticoagulant medications may have a harmful effect on bone-healing.

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The orthopaedic surgeon should be informed and mindful of the added variable that anticoagulation may play in the outcomes of fracture treatment and bone-healing.

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Heparin and warfarin appear to have a greater detrimental impact than low-molecular-weight heparin. Factor Xa inhibitors may confer the least risk, with some studies even suggesting the potential for enhancement of bone-healing.

Bone Microthrombus Promotes Bone Loss in Iron Accumulation Rats

In the present study, we investigated the changes of the coagulation state, bone microthrombus, microvascular bed and bone density levels in iron accumulation rats. Meanwhile,the effect of anticoagulation therapy on bone mineral density was further investigated. We established two groups: a control (Ctrl) group and an iron intervention (FAC) group. Changes in coagulation function, peripheral blood cell counts, bone microthrombus, bone vessels and bone mineral density were compared between the two groups. We designed the non-treatment group and treatment group to study the changes of bone mineral density by preventing microthrombus formation with the anticoagulant fondaparinux. We found that the fibrinogen and D-dimer contents were significantly higher, whereas the thrombin time (TT) and prothrombin time (PT) were significantly shorter in the FAC group. After ink staining, the microvascular bed in the FAC group was significantly reduced compared with that in the Ctrl group. HE and Martius Scarlet Blue (MSB) staining showed microthrombus in the bone marrow of the iron accumulation rats. Following anticoagulation therapy, the bone microcirculation vascular bed areas in the treatment group rats were significantly increased. Furthermore, the bone mineral density was increased in the treatment group compared with that in the non-treatment group. Through experiments, we found that the blood in iron accumulation rat was relatively hypercoagulable; moreover, there was microthrombus in the bone marrow, and the bone vascular bed was reduced. Additionally, anticoagulation was helpful for improving bone microcirculation, reducing microthrombus and decreasing bone loss.

miR‑204 inhibits the osteogenic differentiation of mesenchymal stem cells by targeting bone morphogenetic protein 2

Mesenchymal stem cells (MSCs) are used to investigate regeneration and differentiation. MicroRNA-204 (miR-204) in involved in the Runt-related transcription factor 2/alkaline phosphatase/bone morphogenic protein 2 (Runx2/ALP/BMP2) signaling pathway that regulates bone marrow mesenchymal stem cell (BMSC) differentiation; however, the mechanisms underlying the effects of miR-204 are yet to be determined. The aim of the present study was to investigate the effects of miR-204 on BMSC differentiation. BMSCs were derived from rat bone marrow. The expression levels of Runx2, ALP and BMP2 were measured via reverse transcription-quantitative polymerase chain reaction and western blot analyses following transfection of BMSCs with miR-204 agomir or BMP2 expression vector. The ability of the miR-204 gene to directly bind BMP2 mRNA was assessed using dual-luciferase assays. Ossification was measured via alizarin red stain assays. It was observed that the expression levels of Runx2 and ALP increased over time, whereas those of miR-204 decreased; additionally, miR-204 agomir upregulation inhibited the expression of Runx2, ALP and BMP2 in BMSCs. It was revealed that miR-204 directly interacted with BMP2 mRNA, and that transfection with miR-204 agomir suppressed ossification in BMSCs by targeting the BMP2/Runx2/ALP signaling pathway.

Heparin Differentially Impacts Gene Expression of Stromal Cells from Various Tissues

Pooled human platelet lysate (pHPL) is increasingly used as replacement of animal serum for manufacturing of stromal cell therapeutics. Porcine heparin is commonly applied to avoid clotting of pHPL-supplemented medium but the influence of heparin on cell behavior is still unclear. Aim of this study was to investigate cellular uptake of heparin by fluoresceinamine-labeling and its impact on expression of genes, proteins and function of human stromal cells derived from bone marrow (BM), umbilical cord (UC) and white adipose tissue (WAT). Cells were isolated and propagated using various pHPL-supplemented media with or without heparin. Flow cytometry and immunocytochemistry showed differential cellular internalization and lysosomal accumulation of heparin. Transcriptome profiling revealed regulation of distinct gene sets by heparin including signaling cascades involved in proliferation, cell adhesion, apoptosis, inflammation and angiogenesis, depending on stromal cell origin. The influence of heparin on the WNT, PDGF, NOTCH and TGFbeta signaling pathways was further analyzed by a bead-based western blot revealing most alterations in BM-derived stromal cells. Despite these observations heparin had no substantial effect on long-term proliferation and in vitro tri-lineage differentiation of stromal cells, indicating compatibility for clinically applied cell products.

Culture Medium Supplements Derived from Human Platelet and Plasma: Cell Commitment and Proliferation Support

Present cell culture medium supplements, in most cases based on animal sera, are not fully satisfactory especially for the in vitro expansion of cells intended for human cell therapy. This paper refers to (i) an heparin-free human platelet lysate (PL) devoid of serum or plasma components (v-PL) and (ii) an heparin-free human serum derived from plasma devoid of PL components (Pl-s) and to their use as single components or in combination in primary or cell line cultures. Human mesenchymal stem cells (MSC) primary cultures were obtained from adipose tissue, bone marrow, and umbilical cord. Human chondrocytes were obtained from articular cartilage biopsies. In general, MSC expanded in the presence of Pl-s alone showed a low or no proliferation in comparison to cells grown with the combination of Pl-s and v-PL. Confluent, growth-arrested cells, either human MSC or human articular chondrocytes, treated with v-PL resumed proliferation, whereas control cultures, not supplemented with v-PL, remained quiescent and did not proliferate. Interestingly, signal transduction pathways distinctive of proliferation were activated also in cells treated with v-PL in the absence of serum, when cell proliferation did not occur, indicating that v-PL could induce the cell re-entry in the cell cycle (cell commitment), but the presence of serum proteins was an absolute requirement for cell proliferation to happen. Indeed, Pl-s alone supported cell growth in constitutively activated cell lines (U-937, HeLa, HaCaT, and V-79) regardless of the co-presence of v-PL. Plasma- and plasma-derived serum were equally able to sustain cell proliferation although, for cells cultured in adhesion, the Pl-s was more efficient than the plasma from which it was derived. In conclusion, the cells expanded in the presence of the new additives maintained their differentiation potential and did not show alterations in their karyotype.

The effect of a new oral anticoagulant (Rivaroxaban) on implants pull-out strength. An experimental study in rats

OBJECTIVES

Thromboprophylaxis reduces the risk of surgery related deep venous thrombosis and pulmonary embolism. The classical anticoagulants (heparin and LWMH) were associated with systemic osteoporosis, poor bone healing and materials' osseointegration. There is a lack of data concerning the effect of the new orally administered anticoagulants on osseointegration. The aim of this study is to investigate the possible effect of rivaroxaban, a direct anti-Xa factor, on osseointegration.

METHODS

Twenty eight white, male, Wistar rats were divided into two groups: Group A, study group (n=14) and group B, control group (n=14). In all animals under general anesthesia one screw was inserted on the right tibia. For twenty eight days the animals of group A received intraperitoneal rivaroxaban injections 5mgr/kgr every day. The animals of group B received intraperitoneal equal amount of normal saline injections. At the end of the four weeks all animals were sacrificed and their right tibias were excised and underwent the pull-out test.

RESULTS

The mean values of pull-out test were 92,10±19,12N for the control group and 95,46±21,02N for the study group. The statistical analysis using t-test showed no significant difference (p=0,665) for the pull-out test.

CONCLUSIONS

These results indicate that Rivaroxaban hasn't got any deleterious effect on the osseointegration of implants on rats.

Lower dosage of aspirin promotes cell growth and osteogenic differentiation in murine bone marrow stromal cells

Background/purpose

The effect of aspirin on bone regeneration remains controversial. This study aimed to determine the effect of various concentrations of aspirin on cell viability, osteogenic differentiation, cell cycle, and apoptosis on ST2 cells to find an effective range of aspirin for bone regeneration induction.

Materials and methods

Cell viability was measured with MTT assay after being stimulated with aspirin for 1 day, 2 days, 3 days, 5 days, and 7 days. Alkaline phosphatase (ALP) activity was measured after cells were treated for 1 day, 3 days, and 7 days. Expression of runt-related transcription factor 2 (Runx-2) was evaluated using Western-blot analysis at 3 days and 7 days. Flow cytometry was used for cell cycle and apoptosis measurement after cells were treated for 48 hours.

Results

Lower concentrations of aspirin (1μΜ and 10μM) promoted cell growth and increased ALP levels and Runx-2 expression, while higher concentrations (100μΜ and 1000μΜ) inhibited cell growth (P < 0.05), and lost their effect on ALP activity after 3 days, while even showing an inhibitory effect on the expression of Runx-2. Aspirin at a concentration of 100μM promoted cell mitosis from the S phase to the G2/M phase, and 1000μM arrested the cell cycle in the resting phase G0/G1 (P < 0.05). Parallel apoptosis/necrosis studies showed the percentage of cells in apoptosis decreased dramatically at any dose of aspirin.

Conclusion

A lower dosage of aspirin could promote ST2 cell growth, osteogenic differentiation, and inhibit their apoptosis which indicates that aspirin can be used as an alternative for bone regeneration.

Heparin affects human bone marrow stromal cell fate: Promoting osteogenic and reducing adipogenic differentiation and conversion

Heparins are broadly used for the prevention and treatment of thrombosis and embolism. Yet, osteoporosis is considered to be a severe side effect in up to one third of all patients on long-term treatment. However, the mechanisms underlying this clinical problem are only partially understood. To investigate if heparin affects differentiation of skeletal precursors, we examined the effects of heparin on the osteogenic and adipogenic lineage commitment and differentiation of primary human bone marrow stromal cells (hBMSCs). Due to the known inverse relationship between adipogenesis and osteogenesis and the capacity of pre-differentiated cells to convert into the respective other lineage, we also determined heparin effects on osteogenic conversion and adipogenic differentiation/conversion. Interestingly, heparin did not only significantly increase mRNA expression and enzyme activity of the osteogenic marker alkaline phosphatase (ALP), but it also promoted mineralization during osteogenic differentiation and conversion. Furthermore, the mRNA expression of the osteogenic marker bone morphogenic protein 4 (BMP4) was enhanced. In addition, heparin administration partly prevented adipogenic differentiation and conversion demonstrated by reduced lipid droplet formation along with a decreased expression of adipogenic markers. Moreover, luciferase reporter assays, inhibitor experiments and gene expression analyses revealed that heparin had putative permissive effects on osteogenic signaling via the BMP pathway and reduced the mRNA expression of the Wnt pathway inhibitors dickkopf 1 (DKK1) and sclerostin (SOST). Taken together, our data show a rather supportive than inhibitory effect of heparin on osteogenic hBMSC differentiation and conversion in vitro. Further studies will have to investigate the net effects of heparin administration on bone formation versus bone resorption in vivo to unravel the molecular mechanisms of heparin-associated osteoporosis and reconcile conflicting experimental data with clinical observations.

The Effect of Low Molecular Weight Heparins on Fracture Healing

Venous Thromboembolism is a serious complication in the trauma patient. The most commonly studied and used anticoagulant treatment in prophylaxis of thrombosis is heparin. The prolonged use of unfractionated heparin has been connected with increased incidence of osteoporotic fractures. Low molecular-weight-heparins (LMWHs) have been the golden rule in antithrombotic therapy during the previous two decades as a way to overcome the major drawbacks of unfractioned heparin. However there are few studies reporting the effects of LMWHs on bone repair after fractures. This review presents the studies about the effects of LMWHs on bone biology (bone cells and bone metabolism) and underlying the mechanisms by which LMWHs may impair fracture healing process. The authors' research based on literature concluded that there are no facts and statistics for the role of LMWHs on fracture healing process in humans and the main body of evidence of their role comes from in vitro and animal studies. Further large clinical studies designed to compare different types of LMWHs, in different dosages and in different patient or animal models are needed for exploring the effects of LMWHs on fracture healing process.

Current and future treatments of secondary osteoporosis

Osteoporosis is commonly associated with menopause and ageing. It can, however, also be caused by diseases, lifestyle, genetic diseases, drug therapies and other therapeutic interventions. In cases of secondary osteoporosis, a common rule is the management of the underlying condition. Healthy habits and calcium and vitamin D supplementation are also generally advised. In cases of high risk of fracture, specific antiosteoporosis medications should be prescribed. For most conditions, the available evidence is limited. Special attention should be paid to possible contraindications of drugs used for the treatment of postmenopausal or senile osteoporosis. Bisphosphonates are the most widely used drugs in secondary osteoporosis, and denosumab or teriparatide have been also assessed in some cases. Important research is needed to develop more tailored strategies, specific to the peculiarities of the different types of secondary osteoporosis.

Identification of pro- and anti-proliferative oligosaccharides of heparins

Heparins, unfractionated heparin (UFH) and low molecular weight heparins (LMWHs), are heterogeneous mixtures of anticoagulant and non-anticoagulant oligosaccharides. In addition to their well-known anticoagulant effect, heparins have shown to mediate a wide range of non-anticoagulant effects, including the modulation of cellular growth. However, contradictory results have been reported with regard to their effects on cellular proliferation, with some studies suggesting anti-proliferative while others indicating pro-proliferative effects. This study investigated the proliferation of human colonic epithelial cancer cells in the presence of UFH and LMWHs (enoxaparin and dalteparin). In our experimental setting, all heparins caused a dose-dependent reduction in cellular growth, which correlated well with the induction of cell cycle arrest in the G₁ phase and which was not associated with significant changes in cell viability. The effects on cellular proliferation of 14 different oligosaccharides of enoxaparin obtained through ion-exchange chromatography were also assessed. Surprisingly, only two oligosaccharides showed distinctive anti-proliferative effects while the majority of oligosaccharides actually stimulated proliferation. Interestingly, the smallest oligosaccharide devoid of any anticoagulant activity showed the strongest anti-proliferative effect. Notably, heparins are currently standardised only according to their anticoagulant activity but not based on other non-anticoagulant properties. Our results indicate that slight differences in the composition of heparins' non-anticoagulant oligosaccharides, due to different origins of material and preparation methods, have the potential to cause diverse effects and highlight the need for additional characterisation of non-anticoagulant activities.

Heparin concentration is critical for cell culture with human platelet lysate

BACKGROUND AIMS

Culture media for mesenchymal stromal cells (MSCs) are generally supplemented with fetal bovine serum. Human platelet lysate (hPL) has been proven to be a very effective alternative without the risk of xenogeneic infections or immune reactions. In contrast to fetal bovine serum, hPL comprises plasma, and anticoagulants-usually unfractionated heparin (UFH)-need to be added to prevent gel formation.

METHODS

Cultures of MSCs in hPL media with various concentrations of UFH and enoxaparin, a low-molecular-weight heparin (LMWH), were systematically compared with regard to proliferation, fibroblastoid colony-forming unit frequency, immunophenotype and in vitro differentiation.

RESULTS

At least 0.61 IU/mL UFH or 0.024 mg/mL LMWH was necessary for reliable prevention of coagulation of hPL pools used in this study. Higher concentrations impaired cellular proliferation in a dose-dependent manner even without benzyl alcohol, which is commonly added to heparins as a bacteriostatic agent. Colony-forming unit frequency was also reduced at higher heparin concentrations, particularly with LMWH, whereas no significant effect was observed on cellular morphology or immunophenotype. High concentrations of heparins reduced the in vitro differentiation toward adipogenic and osteogenic lineages.

CONCLUSIONS

Heparin concentration is critical for culture of MSCs in hPL media; this is of particular relevance for cellular therapy where cell culture procedures need to be optimized and standardized.

Human embryonic stem cell-derived mesenchymal stroma cells (hES-MSCs) engraft in vivo and support hematopoiesis without suppressing immune function: implications for off-the shelf ES-MSC therapies

Mesenchymal stroma cells (MSCs) have a high potential for novel cell therapy approaches in clinical transplantation. Commonly used bone marrow-derived MSCs (BM-MSCs), however, have a restricted proliferative capacity and cultures are difficult to standardize. Recently developed human embryonic stem cell-derived mesenchymal stroma cells (hES-MSCs) might represent an alternative and unlimited source of hMSCs. We therefore compared human ES-cell-derived MSCs (hES-MP002.5 cells) to normal human bone marrow-derived MSCs (BM-MSCs). hES-MP002.5 cells had lower yet reasonable CFU-F capacity compared with BM-MSC (8±3 versus 29±13 CFU-F per 100 cells). Both cell types showed similar immunophenotypic properties, i.e. cells were positive for CD105, CD73, CD166, HLA-ABC, CD44, CD146, CD90, and negative for CD45, CD34, CD14, CD31, CD117, CD19, CD 271, SSEA-4 and HLA-DR. hES-MP002.5 cells, like BM-MSCs, could be differentiated into adipocytes, osteoblasts and chondrocytes in vitro. Neither hES-MP002.5 cells nor BM-MSCs homed to the bone marrow of immune-deficient NSG mice following intravenous transplantation, whereas intra-femoral transplantation into NSG mice resulted in engraftment for both cell types. In vitro long-term culture-initiating cell assays and in vivo co-transplantation experiments with cord blood CD34+ hematopoietic cells demonstrated furthermore that hES-MP002.5 cells, like BM-MSCs, possess potent stroma support function. In contrast to BM-MSCs, however, hES-MP002.5 cells showed no or only little activity in mixed lymphocyte cultures and phytohemagglutinin (PHA) lymphocyte stimulation assays. In summary, ES-cell derived MSCs might be an attractive unlimited source for stroma transplantation approaches without suppressing immune function.

The mechanisms of nadroparin-mediated inhibition of proliferation of two human lung cancer cell lines

OBJECTIVES

Clinical data suggest that heparin treatment improves survival of lung cancer patients, but the mechanisms involved are not fully understood. We investigated whether low molecular weight heparin nadroparin, directly affects lung cancer cell population growth in conventionally cultured cell lines.

MATERIALS AND METHODS

A549 and CALU1 cells' viability was assessed by MTT and trypan blue exclusion assays. Cell proliferation was assessed using 5-bromo-2-deoxyuridine incorporation. Apoptosis and cell-cycle distribution were analysed by flow cytometry; cyclin B1, Cdk1, p-Cdk1 Cdc25C, p-Cdc25C and p21 expressions were analysed by western blotting. mRNA levels were analysed by real time RT-PCR.

RESULTS

Nadroparin inhibited cell proliferation by 30% in both cell lines; it affected the cell cycle in A549, but not in CALU-1 cells, inducing arrest in the G(2) /M phase. Nadroparin in A549 culture inhibited cyclin B1, Cdk1, Cdc25C and p-Cdc25C, while levels of p-Cdk1 were elevated; p21 expression was not altered. Dalteparin caused a similar reduction in A549 cell population growth; however, it did not alter cyclin B1 expression as expected, based on previous reports. Fondaparinux caused minimal inhibition of A549 cell population growth and no effect on either cell cycle or cyclin B1 expression.

CONCLUSIONS

Nadroparin inhibited proliferation of A549 cells by inducing G(2) /M phase cell-cycle arrest that was dependent on the Cdc25C pathway, whereas CALU-1 cell proliferation was halted by as yet not elucidated modes.