The anti-osteoporotic activity of amine-carboxyboranes in rodents

Studies related to osteosarcoma and metabolism from 1990 to 2022: A visual analysis and bibliometric study

BACKGROUND

Osteosarcoma is the most common primary bone tumor, its high incidence of metastasis and poor prognosis have led to a great deal of concern for osteosarcoma. In many cancer types, metabolic processes are important for tumor growth progression, so interfering with the metabolic processes of osteosarcoma may be a therapeutic option to stall osteosarcoma progression. A key mechanism of how metabolic processes contribute to the growth and survival of various cancers, including osteosarcoma, is their ability to support tumor cell metabolism. Research related to this field is a direction of great importance and potential. However, to our knowledge, no bibliometric studies related to this field have been published, and we will fill this research gap.

METHODS

Publications were retrieved on January 1, 2023 from the 1990-2022 Science Citation Index of the Web of Science Core Collection. The Bibliometrix package in R software, VOSviewer and CiteSpace software were used to analyze our research directions and to visualize global trends and hotspots in osteosarcoma and metabolism related research.

RESULTS

Based on the search strategy, 833 articles were finally filtered. In this area of research related to osteosarcoma metabolism, we found that China, the United States and Japan are the top 3 countries in terms of number of articles published, and the journals and institutions that have published the most research in this area are Journal of bone and mineral research, Shanghai Jiao Tong University. In addition, Baldini, Nicola, Reddy, Gs and Avnet, Sofia are the top three authors in terms of number of articles published in studies related to this field. The most popular keywords related to the field in the last 30 years are "metabolism" and "expression", which will guide the possible future directions of the field.

CONCLUSION

We used Bibliometrix, VOSviewer, and Citespace to visualize and bibliometrically analyze the current status and possible future hotspots of research in the field of osteosarcoma metabolism. Possible future hotspots in this field may focus on the related terms "metabolism", "expression", and "migraation".

Are blood lipids risk factors for fracture? Integrative evidence from instrumental variable causal inference and mediation analysis using genetic data

BACKGROUND

The relationship between lipids and the risk of fracture is currently controversial and whether such association is causal remains elusive.

METHODS

We performed two-sample inverse variance weighted (IVW) Mendelian randomization (MR) analyses to evaluate causal effects of four lipids (i.e. high-density lipoprotein cholesterol [HDL], low-density lipoprotein cholesterol [LDL], total cholesterol [TC] and triglyceride [TG]) on fracture or bone mineral density (BMD) with summary statistics from large scale genome-wide association studies (up to ~190,000 for lipids, ~66,628 for BMD and ~53,000 for fracture). We validated our MR results with extensive sensitive analyses including MR-PRESSO and MR-Egger regression. Multivariable analyses were implemented to investigate whether other lipids (i.e. LDL and TG) may confound the causal effect of HDL on fracture and mediation analyses were conducted to assess indirect effects of lipids on fracture mediated by BMD.

RESULTS

The IVW MR showed there existed a statistically significant association between HDL and fracture, with the odd ratio (OR) per standard deviation change of HDL on fracture being 1.12 (95% CI: 1.02-1.22, p = 1.20E-02). HDL was also detected to be causally associated with BMD (beta = -0.116; 95% CI: -0.182 ~ -0.050, p = 5.47E-04). These associations were further confirmed by the weighted median and maximum likelihood methods, with the MR-Egger regression removing the possibility of pleiotropy and the multivariable analysis excluding the confounding effect of other lipids on HDL. Negative associations of HDL with BMD among the elderly and with BMD at the lumbar spine were also discovered. However, no causal associations were detected between other lipids (OR = 0.87, 95% CI: 0.74-1.03, p = .107 for LDL; OR = 1.03; 95% CI: 0.88-1.21, p = .696 for TC and OR = 1.04; 95% CI: 0.90-1.20, p = .610 for TG) and fracture; whereas TG was positively associated BMD (beta = 0.184; 95% CI: 0.048-0.319, p = 7.93E-03). Finally, the mediation effect of BMD was estimated to be -0.116 (95% CI: -0.182 to -0.05, p = 5.47E-04) for HDL or 0.184 (95% CI: 0.048-0.319, p = 7.93E-03) for TG, implying HDL and TG could be indirectly associated with fracture risk via the pathway of BMD.

CONCLUSION

Our study is supportive of the causal relationship between HDL and fracture but offers little direct evidence for causal associations between other lipids and fracture, and further reveals HDL and TG may have an indirect influence on fracture mediated by BMD.

Association of high-density lipoprotein, triglycerides, and homocysteine with bone mineral density in young Indian tribal women

This study investigated association between lipids and homocysteine (Hcy) with bone mineral density (BMD) in young women as opposed to previous studies on elderly women. HDL, triglyceride, and Hcy are significantly associated with BMD in young women and tobacco and alcohol consumption have no effect on this association.

PURPOSE

The present study investigates whether the association of serum lipids and homocysteine (Hcy) with bone mineral density (BMD) reported mostly in elderly population can be generalized to young or premenopausal women, consequently suggesting screening of young women with low BMD for dyslipidemia or any cardiovascular events and vice versa.

METHODS

Women (n = 293, aged 20-47 years) from Northeast India belonging to Tibeto-Burman origin were enrolled. Information about their physical and clinical attributes were collected by a structured questionnaire. Their BMDs at lumbar spine and femur were measured by dual-energy X-ray absorptiometry (DXA) and sera were profiled for lipid parameters and Hcy by auto-analyzer and ELISA, respectively. Women consuming tobacco and/or alcohol were grouped as consumers and others as non-consumers for the analysis.

RESULTS

Positive correlation of BMD with HDL (spine and femur r = 0.38, p < 0.0001) and triglyceride (spine r = 0.534, p < 0.0001; femur r = 0.423, p < 0.0001) was observed, whereas Hcy correlated negatively with BMD (spine r = - 0.189, p = 0.0026; femur r = - 0.273, p < 0.0001). LDL showed a weak negative correlation with BMD (spine r = - 0.128, p = 0.0283; femur r = - 0.199, p = 0.0006). However, after adjusting for age, BMI, and consumption, HDL, triglyceride, and Hcy continued to show significant correlation with BMD at both the sites. Logistic regression analyses indicated that HDL, triglyceride, and Hcy were significant predictors of osteopenia and osteoporosis in our study cohort; however, consumption did not contribute to its prediction.

CONCLUSION

Low levels of HDL and triglyceride and high levels of Hcy are significantly associated with osteopenia and osteoporosis in young Northeast Indian women.

The importance of boron in biological systems

Boron is an essential element for plants and probably essential for human and animal health. Boron has a broad range of physiological effects on biological systems at low concentrations, whereas it is toxic to at high concentrations. Eventhough there are many studies on boron's biological effects and toxicity, more information is needed to understand the mechanisms of its action. The aim of the current work is to review boron's function, transport and toxicity in different biological systems.

High cholesterol diet increases osteoporosis risk via inhibiting bone formation in rats

AIM

To investigate the effects of high cholesterol diet on the development of osteoporosis and the underlying mechanisms in rats.

METHODS

Female Sprague-Dawley rats were randomly separated into 3 groups: (1) the high cholesterol fed rats were fed a high cholesterol diet containing 77% normal diet food, 3% cholesterol and 20% lard for 3 months; (2) ovariectomised (OVX) rats were bilaterally ovariectomised and fed a standard diet; and (3) the control rats were fed the standard diet. Bone mineral density (BMD) of the rats was measured using dual-energy X-ray absorptiometry. Serum levels of oestradiol (E2), osteocalcin (BGP) and carboxy-terminal collagen crosslinks (CTX) were measured using ELISA. Gene expression profile was determined with microarray. Mouse osteoblast cells (MC3T3-E1) were used for in vitro study. Proliferation, differentiation and oxidative stress of the osteoblasts were investigated using MTT, qRT-PCR and biochemical methods.

RESULTS

In high cholesterol fed rats, the femur BMD and serum BGP level were significantly reduced, while the CTX level was significantly increased. DNA microarray analysis showed that 2290 genes were down-regulated and 992 genes were up-regulated in this group of rats. Of these genes, 1626 were also down-regulated and 1466 were up-regulated in OVX rats. In total, 370 genes were up-regulated in both groups, and 976 genes were down-regulated. Some of the down-regulated genes were found to code for proteins involved in the transforming growth factor beta (TGF-β)/bone morphogenic protein (BMP) and Wnt signaling pathways. The up-regulated genes were found to code for IL-6 and Ager with bone-resorption functions. Treatment of MC3T3-E1 cells with cholesterol (12.5-50 μg/mL) inhibited the cell proliferation and differentiation in vitro in a concentration-dependent manner. The treatment also concentration-dependently reduced the expression of BMP2 and Cbfa1, and increased the oxidative injury in MC3T3-E1 cells.

CONCLUSION

The results suggest a close correlation between hypercholesterolaemia and osteoporosis. High cholesterol diet increases the risk of osteoporosis, possible via inhibiting the differentiation and proliferation of osteoblasts.

Synthesis and Structural Investigation of Internally Coordinated α-Amidoboronic Acids

[structure: see text] Six new N-acyl-boroGly derivatives, along with their N-acyl-boroSar analogues, have been synthesized by modification of conventional procedures. Structural characterization of these alpha-amidoboronic acids was accomplished by extensive use of 11B and 1H NMR spectroscopy. These compounds were prepared to determine the extent of intramolecular B-O dative bond formation within the context of a five-membered (:O=C-N-C-B) ring motif. It is shown that the formation of such dative bonds depends on the nature of the substituents at both the acyl carbon and the nitrogen atoms. Computational evidence from second-order Møller-Plesset perturbation theory is provided in support of these findings.

Influence of boron supplementation on vertebral and femoral bone mass in rats on strenuous treadmill exercise. A morphometric, densitometric, and histomorphometric study

We studied the effect of boron supplement on experimental osteopenia caused by strenuous exercise in 93- d-old female Wistar rats. A control group of 15 rats was not manipulated. The exercise group of 30 rats was divided into 2 groups of 15 rats each, one that was fed a diet supplemented with 50 mg/kg of boron in the form of Na(2)B(4)O(7), and other that, did not receive a boron supplement. The length and weight were determined in the femur and fifth lumbar vertebra and the bone mineral content and density were assessed through densitometry, and trabecular bone volume, trabecular number, trabecular thickness, and trabecular separation with histomorphometry. The femur length and weight, and vertebra weight, and femur and vertebra bone mineral content and density were significantly lower and the trabecular separation was higher in the exercise group than in the others (p < 0.005 in all). The femur weight, bone mineral content and density, trabecular bone volume and trabecular thickness, were significantly higher in the exercise plus boron group (p < 0.005 to 0.0001). It was concluded that boron preserves bone mass in rats that have been exposed to intense exercise.

Mechanisms implicated in the effects of boron on wound healing

Recently, we demonstrated that boron modulates the turnover of the extracellular matrix and increases TNFalpha release. In the present study, we used an in vitro test to investigate the direct effect of boron on specific enzymes (elastase, trypsin-like enzymes, collagenase and alkaline phosphatase) implicated in extracellular matrix turnover. Boron decreased the elastase and alkaline phosphatase activity, but had no effect on trypsin and collagenase activities. The effect of boron on the enzyme activities was also tested in fibroblasts considered as an in vivo test. In contrast to the results obtained in vitro, boron enhanced the trypsin-like, collagenase, and cathepsin D activities in fibroblasts. Boron did not modify the generation of free radicals compared to the control and did not seem to act on the intracellular alkaline phosphatase activity, However, as it did enhance phosphorylation, it can be hypothesized that boron may affect living cells via a mediator, which could be TNFalpha whose transduction signal involves a cascade of phosphorylations.

Relationship between amine-carboxyboranes and TNF alpha for the regulation of cell growth in different tumor cell lines

The amine-carboxyboranes were shown to be synergistic with tumor necrosis factor alpha (TNF alpha) in cytotoxicity and inhibition of DNA synthesis in select types of cancer cells depending on the presence of a TNF alpha high affinity receptor on the membrane of the cell. Initially both TNF alpha and the amine-carboxyboranes reduce the influx of calcium but later cause a significant increase intracellularly. This influx is not linked with the amine-carboxyborane activating the calcitonin receptor in the tumor cells. Neither the agents nor TNF alpha directly inhibits DNA topoisomerase II activity but both did cause decreased phosphorylation of the enzyme by protein kinase C (PKC). The two agents caused synergistic inhibition. This event correlated with increased DNA protein linked breaks, DNA fragmentation and cell death. These protein linked breaks are additive with etoposide's effects but the latter agent's mechanism is different than phosphorylation of topoisomerase II. There was no evidence that the DNA fragmentation was caused by a calcium induced endonuclease enzyme in these cancer cells. The low-molecular weight amine-carboxyboranes appear to play an identical function as TNF alpha in its role to cause DNA breaks and fragmentation to cause apoptosis.

Role of lipids in osteoporosis

Cardiovascular disease and osteoporosis together account for most of the morbidity and mortality in our aging population despite significant improvements in treatment. Recently, converging lines of evidence suggest that these 2 diseases share an etiologic factor--that hyperlipidemia contributes not only to atherosclerotic plaque formation, but also to osteoporosis, following a similar biologic mechanism involving lipid oxidation. In vitro studies indicate that lipid products of oxidation promote osteoblastic differentiation of vascular cells and inhibit such differentiation in bone cells. Ex vivo, in vivo, and clinical studies further suggest that lipid-lowering agents reduce both atherosclerotic calcification and osteoporosis. Whether lipid-lowering agents reduce osteoporosis directly or indirectly through lipid reduction remains controversial.

Effects of boron derivatives on extracellular matrix formation

Boric acid solution (3%) dramatically improves wound healing through action on the extracellular matrix, a finding that has been obtained in vitro. Consequently, investigations are presently underway to produce boronated compounds having a therapeutical effectiveness similar to that of boric acid. On the basis of experimental results obtained with boric acid, we examined the effects of boron derivatives on extracellular matrix formation and degradation and analyzed their potential toxicity by using two biological models (chick embryo cartilage and human fibroblasts). The four boron derivatives tested in this study (triethanolamine borate; N-diethyl-phosphoramidate-propylboronique acid; 2,2 dimethylhexyl-1,3-propanediol-aminopropylboronate and 1,2 propanediol-aminopropylboronate) mimicked the effects of boric acid. They induced a decrease of intracellular concentrations in extracellular matrix macromolecules (proteoglycans, proteins)-associated with an increase of their release in culture medium and stimulated the activity of intra- and extracellular proteases. Similarly to boric acid, these actions occurred after exposure of the cells to concentrations of all boron derivatives without apparent toxic effects. The compounds were found to be more toxic than boric acid itself when concentrations were calculated according to their molecular weight. Nevertheless, these in vitro preliminary results demonstrate effects of boron derivatives that may be of therapeutic benefit in wound repair.

In vivo and in vitro effects of boron and boronated compounds

Boron is ubiquitously present in soils and water. Associated with pectin it is essential for vascular plants as a component of cell walls, and it stabilizes cell membranes. It is required for the growth of pollen tubes and is involved in membrane transport, stimulating H(+)-pumping ATPase activity and K+ uptake. However, a high boron concentration in the soils is toxic to plants and some boronated derivatives are used as herbicides. An absolute requirement for boron has not been definitively demonstrated in animals and humans. However, experiments with boron supplementation or deprivation show that boron is involved in calcium and bone metabolism, and its effects are more marked when other nutrients (cholecalciferol, magnesium) are deficient. Boron supplementation increases the serum concentration of 17 beta-estradiol and testosterone but boron excess has toxic effects on reproductive function. Boron may be involved in cerebral function via its effects on the transport across membranes. It affects the synthesis of the extracellular matrix and is beneficial in wound healing. Usual dietary boron consumption in humans is 1-2 mg/day for adults. As boron has been shown to have biological activity, research into the chemistry of boronated compounds has increased. Boronated compounds have been shown to be potent anti-osteoporotic, anti-inflammatory, hypolipemic, anti-coagulant and anti-neoplastic agents both in vitro and in vivo in animals.

Effect of boric acid solution on cartilage metabolism

Pelvic cartilage of chick embryo was used to demonstrate that presence of boron in culture medium decreases synthesis of proteoglycans, collagen and total proteins but on the other hand increases the release of these macromolecules. However, when glucose concentration in culture medium is brought to 22mM, the synthesis decrease is no longer observed, whereas release increase persists. Proteins released into the culture medium included heat shock proteins (70 hsp) and tumor necrosis factor alpha (TNF alpha). The amount of phosphorylated proteins was enhanced in presence of boron while endoprotease activity in cartilage and in culture medium was significantly augmented. The in vitro effects of boric acid may explain its in vivo effect on wound healing.