The stimulation of angiogenesis and collagen deposition by copper

Peptides derived from the copper-binding region of lysyl oxidase exhibit antiangiogeneic properties by inhibiting enzyme activity: an in vitro study

Despite the rigorous research on abnormal angiogenesis, there is a persistent need for the development of new and efficient therapies against angiogenesis-related diseases. The role of Lysyl oxidase (LOX) in angiogenesis and cancer has been established in prior studies. Copper is known to induce the synthesis of LOX, and hence regulates its activity. Hypoxia-induced metastasis is dependent on LOX expression and activity. It has been believed that the inhibition of LOX would be a therapeutic strategy to inhibit angiogenesis. To explore this, we designed peptides (M peptides) from the copper-binding region of LOX and hypothesized them to modulate LOX. The peptides were characterized, and their copper-binding ability was confirmed by mass spectrometry. The M peptides were found to reduce the levels of intracellular copper when the cells were co-treated with copper. The peptides showed promising effect on aortic LOX, recombinant human LOX and LOX produced by human umbilical vein endothelial cells (HUVECs). The study also explores the effect of these peptides on copper and hypoxia-stimulated angiogenic response in HUVECs. It was found that the M peptides inhibited copper/hypoxia-induced LOX activity and inhibited stimulated HUVEC tube formation and migration. This clearly indicated the potential of M peptides in inhibiting angiogenesis, highlighting their role in the formulation of drugs for the same.

The effects of silver ions on copper metabolism in rats

The influence of short and prolonged diet containing silver ions (Ag-diet) on copper metabolism was studied. Two groups of animals were used: one group of adult rats received a Ag-diet for one month (Ag-A1) and another group received a Ag-diet for 6 months from birth (Ag-N6). In Ag-A1 rats, the Ag-diet caused a dramatic decrease of copper status indexes that was manifested as ceruloplasmin-associated copper deficiency. In Ag-N6 rats, copper status indexes decreased only 2-fold as compared to control rats. In rats of both groups, silver entered the bloodstream and accumulated in the liver. Silver was incorporated into ceruloplasmin (Cp), but not SOD1. In the liver, a prolonged Ag-diet caused a decrease of the expression level of genes, associated with copper metabolism. Comparative spectrophotometric analysis of partially purified Cp fractions has shown that Cp from Ag-N6 rats was closer to holo-Cp by specific enzymatic activities and tertiary structure than Cp from Ag-A1 rats. However, Cp of Ag-N6 differs from control holo-Cp and Cp of Ag-A1 in its affinity to DEAE-Sepharose and in its binding properties to lectins. In the bloodstream of Ag-N6, two Cp forms are present as shown in pulse-experiments on rats with the liver isolated from circulation. One of the Cp isoforms is of hepatic origin, and the other is of extrahepatic origin; the latter is characterized by a faster rate of secretion than hepatic Cp. These data allowed us to suggest that the disturbance of holo-Cp formation in the liver was compensated by induction of extrahepatic Cp synthesis. The possible biological importance of these effects is discussed.

Cuprous oxide nanoparticles inhibit angiogenesis via down regulation of VEGFR2 expression

Angiogenesis is a process that forms new blood capillaries from existing vessels, which is of great physiological and pathological significance. Although recent studies provide evidence that cuprous oxide nanoparticles (CO-NPs) may have biomedical potential, the mechanisms of CO-NPs in angiogenesis have not been investigated to date. We have studied the anti-angiogenic properties of CO-NPs on primary human umbilical vein endothelial cells (HUVECs). We found that CO-NPs were able to induce cell morphology changes and suppress cell proliferation, migration and tube formation in vitro and in vivo dose dependently. Furthermore, CO-NPs could induce cell apoptosis both at the early and late apoptotic stage and induce cell cycle arrest at S phase in a dose dependent manner. As signalling via the vascular endothelial growth factor receptor-2 (VEGFR2) is critical for angiogenic responses, we further explored the expression of VEGFR2 after the treatment of CO-NPs. They were found to inhibit VEGFR2 expression dose and time dependently both at the protein and mRNA level while had no effect on VEGF and VEGFR1 expression. Together, we report for the first time that CO-NPs can act as an anti-angiogenic agent by suppressing VEGFR2 expression, which may be a potential nanomedicine for angiogenesis therapy.

Inhibition of osteogenic differentiation of mesenchymal stem cells by copper supplementation

OBJECTIVES

Copper has been added to scaffolds when investigating bone repair, as an agent to promote vascularization; however, little is known concerning its effect on mesenchymal stem cells (MSCs), which are considered to be the origin of osteoblasts. In this study, we have aimed to elucidate effects of copper on osteogenic differentiation of MSCs.

MATERIALS AND METHODS

Rat bone marrow MSCs (rBMSCs) were used as a model. Their viability was assessed by MTT assay and Roche's CASY cell counter test and calcium deposition was evaluated by staining with alizarin red S. Fluorescent phalloidin F-actin stain was used to evaluate cytoskeletal changes, protein expressions were investigated by western blotting and mRNA levels were analysed using Q-PCR. A rat model for ectopic bone formation was used to assess effects of copper on MSCs in vivo.

RESULTS

Copper supplementation resulted in inhibition of osteogenesis of rBMSCs, along with reduction in expression of a number of osteogenic genes, alkaline phosphatase activity and formation of bone nodules. Cytoskeletal changes to cells during osteogenesis was inhibited by copper supplementation. In vivo study confirmed that copper could inhibit collagen formation whilst promoting angiogenesis.

CONCLUSIONS

Our study demonstrated that copper inhibited osteogenic differentiation of rBMSCs in vitro. The findings caution appropriate use of copper and have laid a foundation for further research.

Understanding of dopant-induced osteogenesis and angiogenesis in calcium phosphate ceramics

General trends in synthetic bone grafting materials are shifting towards approaches that can illicit osteoinductive properties. Pharmacologics and biologics have been used in combination with calcium phosphate (CaP) ceramics, however, they have recently become the target of scrutiny over safety. The importance of trace elements in natural bone health is well documented. Ions, for example, lithium, zinc, magnesium, manganese, silicon, strontium, etc., have been shown to increase osteogenesis and neovascularization. Incorporation of dopants (trace metal ions) into CaPs can provide a platform for safe and efficient delivery in clinical applications where increased bone healing is favorable. This review highlights the use of trace elements in CaP biomaterials, and offers an insight into the mechanisms of how metal ions can enhance both osteogenesis and angiogenesis.

Zinc, copper, and selenium tissue levels and their relation to subcutaneous abscess, minor surgery, and wound healing in humans

Trace element involvement in wounds left to heal by secondary intention needs clarification. We have previously reported faster healing of wounds following acute surgery compared with elective excision of pilonidal sinus disease. The effect of topical zinc on the closure of the excisional wounds was mediocre compared with placebo. In contrast, parenteral zinc, copper, and selenium combined appear effective for wound healing in humans. We have investigated zinc, copper, and selenium with respect to (a) impact of acute versus chronic pilonidal sinus and (b) regional concentrations within granulating wounds treated topically with placebo or zinc in 42 (33 males) pilonidal disease patients. Baseline serum and skin concentrations of copper correlated (r S = 0.351, p = 0.033, n = 37), but not of zinc or selenium. Patients with abscesses had elevated serum C-reactive protein (CRP) and copper levels (+29 %; p < 0.001) compared with the elective patients consistent with the strong correlation between serum copper and CRP (r S = 0.715, p < 0.0005, n = 41). Seven days after elective surgery, serum CRP and copper levels were elevated (p = 0.010) versus preoperative values. The copper concentration in wound edges was higher than in periwound skin (p < 0.0005) and wound base (p = 0.010). Selenium levels were increased in wound edge compared to wound base (p = 0.003). Topical zinc oxide treatment doubled (p < 0.050) zinc concentrations in the three tissue localizations without concomitant significant changes of copper or selenium levels. In conclusion, copper and selenium are mobilized to injured sites possibly to enhance host defense and early wound healing mechanisms that are complementary to the necessity of zinc for matrix metalloproteinase activity.

Non-hepatic tumors change the activity of genes encoding copper trafficking proteins in the liver

To assess the statistical relationship between tumor growth and copper metabolism, we performed a metaanalysis of studies in which patients with neoplasms were characterized according to any of the copper status indexes (atomic copper serum concentration, serum oxidase activity, ceruloplasmin protein content). Our metaanalysis shows that in the majority of cases (more than 3100 patients), tumor growth positively correlates with the copper status indexes. Nude athymic CD-1 nu/nu mice with subcutaneous tumors of human origin, C57Bl/6J mice with murine melanoma and Apc(Min) mice with spontaneously developing adenomas throughout the intestinal tract were studied to experimentally determine the relationship between tumor progression, liver copper metabolism, and copper status indexes. We showed that the copper status indexes increased significantly during tumor growth. In the liver tissue of tumor-bearing mice, ceruloplasmin gene expression, as well as the expression of genes related to ceruloplasmin metallation (CTR1 and ATP7B), increased significantly. Moreover, the presence of an mRNA splice variant encoding a form of ceruloplasmin anchored to the plasma membrane by glycosylphosphatidyl inositol, which is atypical for hepatocytes, was also detected. The ATP7A copper transporter gene, which is normally expressed in the liver only during embryonic copper metabolism, was also activated. Depletion of holo-ceruloplasmin resulted in retardation of human HCT116 colon carcinoma cell growth in nude mice and induced DNA fragmentation in tumor cells. In addition, the concentration of cytochrome c increased significantly in the cytosol, while decreasing in the mitochondria. We discuss a possible trans-effect of developing tumors on copper metabolism in the liver.

Hepatocellular carcinoma in a non-cirrhotic patient with Wilson's disease

We report the exceptional case of hepatocellular carcinoma in a non-cirrhotic patient, whose Wilson’s disease was diagnosed at the unusual age of 58 years. The liver histology revealed macrovesicular steatosis with fibrosis, but no cirrhosis. The disease was treated with D-penicillamine for 3 years until acute discomfort in the right upper quadrant led to detection of multifocal hepatocellular carcinoma, which was successfully resected. The histological examination confirmed the malignant nature of the 4 lesions, which were classified according to Edmondson and Steiner as poorly differentiated hepatocellular carcinoma grade 3. The non-tumoral parenchyma showed 80% steatosis with ballooned cells, lobular inflammation, septal fibrosis but no cirrhosis. Hepatocellular carcinoma is rare in Wilson’s disease, especially in the absence of cirrhosis. The literature’s 28 published cases are reviewed and the contributory role of copper in the hepatocarcinogenic process is discussed.

Bone formation controlled by biologically relevant inorganic ions: role and controlled delivery from phosphate-based glasses

The role of metal ions in the body and particularly in the formation, regulation and maintenance of bone is only just starting to be unravelled. The role of some ions, such as zinc, is more clearly understood due to its central importance in proteins. However, a whole spectrum of other ions is known to affect bone formation but the exact mechanism is unclear as the effects can be complex, multifactorial and also subtle. Furthermore, a significant number of studies utilise single doses in cell culture medium, whereas the continual, sustained release of an ion may initiate and mediate a completely different response. We have reviewed the role of the most significant ions that are known to play a role in bone formation, namely calcium, zinc, strontium, magnesium, boron, titanium and also phosphate anions as well as copper and its role in angiogenesis, an important process interlinked with osteogenesis. This review will also examine how delivery systems may offer an alternative way of providing sustained release of these ions which may effect and potentiate a more appropriate and rapid tissue response.

Time-dependent morphological and biochemical changes following cutaneous thermal burn injury and their modulation by copper nicotinate complex: an animal model

BACKGROUND

Thermal tissue injury is partly mediated by reactive oxygen metabolites. Oxygen free radicals are contributory to local tissue damage following thermal injury and accordingly an interventional therapy using antioxidants may be beneficial. Copper nicotinate complex can scavenge reactive oxygen species (i.e., has antioxidant activity).

OBJECTIVES

To examine time-related morphological and biochemical changes following skin thermal injury and their modulation by copper nicotinate complex.

MATERIALS AND METHODS

An animal model composed of 80 albino rats was established. Ten rats (nonburn group) served as a control group. Seventy rats (burn group) were anesthetized, given a 10% total body surface area, full-thickness burn. Ten rats (from the postburn group) were sacrificed after 24 h (without treatment, i.e., untreated-burn group). The remaining rats were divided into three subgroups (20 rats, each) and were treated topically either with soft paraffin, moist exposed burn ointment (MEBO, a standard therapeutic treatment for burns), or copper nicotinate complex. Five animals from each subgroup were sacrificed every week over a period of 4 weeks. The morphological and biochemical changes were evaluated and compared among the different groups.

RESULTS

High levels of the plasma and skin nitiric oxide (marker of oxidative stress) were observed in the untreated-burn group. These levels were significantly low following the application of copper nicotinate complex. Low levels of plasma and skin superoxide dismutase (marker of oxidative stress) and plasma ceruloplasmin were observed in the untreated-burn group. These levels were significantly high following copper nicotinate complex treatment. The total and differential leukocyte counts were low following the onset of the thermal injury. They gradually returned to normal levels over a 4-week period following the application of MEBO or copper nicotinate complex. Compared to untreated-burn group, postburn-healing changes (resolution of the inflammatory reaction, reepithelization of the epidermis, angiogenesis, deposition of collagen fibers, and recovery of the subcellualr organelles) were significantly accelerated following the application of either MEBO or copper nicotinate complex.

CONCLUSIONS

Application of copper nicotinate complex was associated with improved healing of the thermal burns of the skin. The underlying molecular changes underlying these effects await further investigations.

Nanoneurotoxicity to nanoneuroprotection using biological and computational approaches

Nanoparticles (NPs) that are ∼100 nm in diameter can potentially cause toxicity in the central nervous system (CNS). Although NPs exhibit positive aspects, these molecules primarily exert negative or harmful effects. Thus, the beneficial and harmful effects should be compared. The prevalence of neurodegenerative diseases, such as Alzheimer disease, Parkinson disease, and some brain tumors, has increased. However, the major cause of these diseases remains unknown. NPs have been considered as one of the major potential causes of these diseases, penetrating the human body via different pathways. This review summarizes various pathways for NP-induced neurotoxicity, suggesting the development of strategies for nanoneuroprotection using in silico and biological methods. Studies of oxidative stress associated with gene expression analyses provide efficient information for understanding neuroinflammation and neurodegeneration associated with NPs. The brain is a sensitive and fragile organ, and evolution has developed mechanisms to protect it from injury; however, this protection also hinders the methods used for therapeutic purposes. Thus, brain and CNS-related diseases that are the cause of disability and disorder are the most difficult to treat. There are many obstacles to drug delivery in the CNS, such as the blood brain barrier and blood tumor barrier. Considering these barriers, we have reviewed the strategies available to map NPs using biological techniques. The surface adsorption energy of NPs is the basic force driving NP gathering, protein corona formation, and many other interactions of NPs within biological systems. These interactions can be described using an approach named the biological surface adsorption index. A quantitative structural activity relationship study helps to understand different protein-protein or protein-ligand interactions. Moreover, equilibrium between cerebrovascular permeability is required when a drug is transferred via the circulatory system for the therapy of neurodegenerative diseases. Various drug delivery approaches, such as chemical drug delivery and carrier-mediated drug delivery, have been established to avoid different barriers inhibiting CNS penetration by therapeutic substances. Developing an improved understanding of drug receptors and the sites of drug action, together with advances in medicinal chemistry, will make it possible to design drugs with greatly enhanced activity and selectivity; this may result in a significant increase in the therapeutic index.

Subcellular redistribution and mitotic inheritance of transition metals in proliferating mouse fibroblast cells

Synchrotron X-ray fluorescence microscopy of non-synchronized NIH 3T3 fibroblasts revealed an intriguing redistribution dynamics that defines the inheritance of trace metals during mitosis. At metaphase, the highest density areas of Zn and Cu are localized in two distinct regions adjacent to the metaphase plate. As the sister chromatids are pulled towards the spindle poles during anaphase, Zn and Cu gradually move to the center and partition into the daughter cells to yield a pair of twin pools during cytokinesis. Colocalization analyses demonstrated high spatial correlations between Zn, Cu, and S throughout all mitotic stages, while Fe showed consistently different topographies characterized by high-density spots distributed across the entire cell. Whereas the total amount of Cu remained similar compared to interphase cells, mitotic Zn levels increased almost 3-fold, suggesting a prominent physiological role that lies beyond the requirement of Zn as a cofactor in metalloproteins or messenger in signaling pathways.

Copper-containing mesoporous bioactive glass scaffolds with multifunctional properties of angiogenesis capacity, osteostimulation and antibacterial activity

It is of great importance to develop multifunctional bioactive scaffolds, which combine angiogenesis capacity, osteostimulation, and antibacterial properties for regenerating lost bone tissues. In order to achieve this aim, we prepared copper (Cu)-containing mesoporous bioactive glass (Cu-MBG) scaffolds with interconnective large pores (several hundred micrometer) and well-ordered mesopore channels (around 5 nm). Both Cu-MBG scaffolds and their ionic extracts could stimulate hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) expression in human bone marrow stromal cells (hBMSCs). In addition, both Cu-MBG scaffolds and their ionic extracts significantly promoted the osteogenic differentiation of hBMSCs by improving their bone-related gene expression (alkaline phosphatase (ALP), osteopontin (OPN) and osteocalcin (OCN)). Furthermore, Cu-MBG scaffolds could maintain a sustained release of ibuprofen and significantly inhibited the viability of bacteria. This study indicates that the incorporation of Cu(2+) ions into MBG scaffolds significantly enhances hypoxia-like tissue reaction leading to the coupling of angiogenesis and osteogenesis. Cu(2+) ions play an important role to offer the multifunctional properties of MBG scaffold system. This study has demonstrated that it is possible to develop multifunctional scaffolds by combining enhanced angiogenesis potential, osteostimulation, and antibacterial properties for the treatment of large bone defects.

Progress and challenges in biomaterials used for bone tissue engineering: bioactive glasses and elastomeric composites

Driven by the increasing economic burden associated with bone injury and disease, biomaterial development for bone repair represents the most active research area in the field of tissue engineering. This article provides an update on recent advances in the development of bioactive biomaterials for bone regeneration. Special attention is paid to the recent developments of sintered Na-containing bioactive glasses, borate-based bioactive glasses, those doped with trace elements (such as Cu, Zn, and Sr), and novel elastomeric composites. Although bioactive glasses are not new to bone tissue engineering, their tunable mechanical properties, biodegradation rates, and ability to support bone and vascular tissue regeneration, as well as osteoblast differentiation from stem and progenitor cells, are superior to other bioceramics. Recent progresses on the development of borate bioactive glasses and trace element-doped bioactive glasses expand the repertoire of bioactive glasses. Although boride and other trace elements have beneficial effects on bone remodeling and/or associated angiogenesis, the risk of toxicity at high levels must be highly regarded in the design of new composition of bioactive biomaterials so that the release of these elements must be satisfactorily lower than their biologically safe levels. Elastomeric composites are superior to the more commonly used thermoplastic-matrix composites, owing to the well-defined elastic properties of elastomers which are ideal for the replacement of collagen, a key elastic protein within the bone tissue. Artificial bone matrix made from elastomeric composites can, therefore, offer both sound mechanical integrity and flexibility in the dynamic environment of injured bone.

Lysyl oxidase and enhancement of cell proliferation and angiogenesis in oral squamous cell carcinoma

BACKGROUND

Lysyl oxidase (LOX) is a copper-dependent enzyme that cross-links collagen and elastin in the extracellular matrix. LOX overexpressed in various tumors. The manner in which LOX affects tumor growth remains controversial.

METHODS

Chemical treatment and gene transfection were used to induce LOX overexpression or inhibition in cell lines SAS and SVEC4-10. LOX mRNA, protein, and activity were confirmed before tube formation assay and tumorigenesis. The microvessels in the tumor section were detected by immunostaining CD31-positive endothelial cells.

RESULTS

LOX overexpression and copper induction of LOX activity increased SVEC4-10 tube formation. LOX silencing and β-aminopropionitrile inhibition of LOX activity had opposite effects. LOX overexpression increased proliferation and proliferating cell nuclear antigen expression. High LOX expression clones increased tumor size in a tumorigenesis model. The microvascular numbers were higher in LOX overexpression tumors than in control tumors.

CONCLUSION

LOX can induce cell proliferation and angiogenesis in oral squamous cell carcinoma.

Copper-releasing, boron-containing bioactive glass-based scaffolds coated with alginate for bone tissue engineering

The aim of this study was to synthesize and characterize new boron-containing bioactive glass-based scaffolds coated with alginate cross-linked with copper ions. A recently developed bioactive glass powder with nominal composition (wt.%) 65 SiO2, 15 CaO, 18.4 Na2O, 0.1 MgO and 1.5 B2O3 was fabricated as porous scaffolds by the foam replica method. Scaffolds were alginate coated by dipping them in alginate solution. Scanning electron microscopy investigations indicated that the alginate effectively attached on the surface of the three-dimensional scaffolds leading to a homogeneous coating. It was confirmed that the scaffold structure remained amorphous after the sintering process and that the alginate coating improved the scaffold bioactivity and mechanical properties. Copper release studies showed that the alginate-coated scaffolds allowed controlled release of copper ions. The novel copper-releasing composite scaffolds represent promising candidates for bone regeneration.

Copper stimulates growth of human umbilical vein endothelial cells in a vascular endothelial growth factor-independent pathway

Studies in vivo have shown that dietary copper (Cu) supplementation reverses pressure overload-induced cardiac hypertrophy in a mouse model, which is vascular endothelial growth factor (VEGF)-dependent and correlates with enhanced angiogenesis. Because Cu stimulation of endothelial cell growth and differentiation would play a critical role in angiogenesis, the present study was undertaken to examine the effect of Cu on growth of human umbilical vein endothelial cells (HUVECs) in cultures. The HUVECs were treated with CuSO4 at a final concentration of 5 μmol/L Cu element in cultures or with a Cu chelator, tetraethylenepentamine (TEPA), at a final concentration of 25 μmol/L in cultures. Cell growth and Cu effect on cell cycle were determined. In addition, the effect of Cu on VEGF and endothelial nitric oxide synthase (eNOS) mRNA levels was determined, and anti-VEGF antibody and siRNA targeting eNOS were applied to determine the role of VEGF or eNOS in the Cu effect on cell growth. Cu significantly stimulated and TEPA significantly inhibited cell growth, and the TEPA effect was blocked by excess Cu. Cu increased the number of cells in the S phase and correspondingly decreased the number in the G1 phase. Interestingly, Cu did not increase the level of VEGF mRNA, but significantly increased eNOS mRNA. Furthermore, neutralizing VEGF by anti-VEGF antibody did not suppress Cu stimulation of cell growth. However, siRNA targeting eNOS completely blocked Cu reversal of TEPA inhibition of cell growth. The data demonstrate that Cu stimulation of HUVEC cell growth is VEGF-independent, but eNOS-dependent.

Metallic ions as therapeutic agents in tissue engineering scaffolds: an overview of their biological applications and strategies for new developments

This article provides an overview on the application of metallic ions in the fields of regenerative medicine and tissue engineering, focusing on their therapeutic applications and the need to design strategies for controlling the release of loaded ions from biomaterial scaffolds. A detailed summary of relevant metallic ions with potential use in tissue engineering approaches is presented. Remaining challenges in the field and directions for future research efforts with focus on the key variables needed to be taken into account when considering the controlled release of metallic ions in tissue engineering therapeutics are also highlighted.

Bioinorganics and biomaterials: bone repair

The field of bioinorganics is well established in the development of a variety of therapies. However, their application to bone regeneration, specifically by way of localized delivery from functional implants, is in its infancy and is the topic of this review. The toxicity of inorganics is species, dose and duration specific. Little is known about how inorganic ions are effective therapeutically since their use is often the result of serendipity, observations from nutritional deficiency or excess and genetic disorders. Many researchers point to early work demonstrating a role for their element of interest as a micronutrient critical to or able to alter bone growth, often during skeletal development, as a basis for localized delivery. While one can appreciate how a deficiency can cause disruption of healing, it is difficult to explain how a locally delivered excess in a preclinical model or patient, which is presumably of normal nutritional status, can evoke more bone or faster healing. The review illustrates that inorganics can positively affect bone healing but various factors make literature comparisons difficult. Bioinorganics have the potential to have just as big an impact on bone regeneration as recombinant proteins without some of the safety concerns and high costs.

A review of the biological response to ionic dissolution products from bioactive glasses and glass-ceramics

Several inorganic materials such as special compositions of silicate glasses, glass-ceramics and calcium phosphates have been shown to be bioactive and resorbable and to exhibit appropriate mechanical properties which make them suitable for bone tissue engineering applications. However, the exact mechanism of interaction between the ionic dissolution products of such inorganic materials and human cells are not fully understood, which has prompted considerable research work in the biomaterials community during the last decade. This review comprehensively covers literature reports which have investigated specifically the effect of dissolution products of silicate bioactive glasses and glass-ceramics in relation to osteogenesis and angiogenesis. Particularly, recent advances made in fabricating dense biomaterials and scaffolds doped with trace elements (e.g. Zn, Sr, Mg, and Cu) and investigations on the effect of these elements on the scaffold biological performance are summarized and discussed in detail. Clearly, the biological response to artificial materials depends on many parameters such as chemical composition, topography, porosity and grain size. This review, however, focuses only on the ion release kinetics of the materials and the specific effect of the released ionic dissolution products on human cell behaviour, providing also a scope for future investigations and identifying specific research needs to advance the field. The biological performance of pure and doped silicate glasses, phosphate based glasses with novel specific compositions as well as several other silicate based compounds are discussed in detail. Cells investigated in the reviewed articles include human osteoblastic and osteoclastic cells as well as endothelial cells and stem cells.