Selected physiological effects of boron compounds for animals and humans. A review

Evaluation of Possible Toxic Effects of Boric Acid in Palourde Clam (Ruditapes decussatus) Through Histological Changes and Oxidative Responses

The extensive utilization of boric acid, particularly in industrial and agricultural sectors, also engenders concerns regarding the toxicity of boron and its derivatives. Particularly, the behavior of boric acid at increasing concentrations in aquatic ecosystems remains poorly understood. In light of these concerns, this study aimed to investigate the toxicity of boric acid in bivalves, which occupy a critical position in the food chain. Specimens of Ruditapes decussatus, which had not been previously exposed to any pollutants and were cultivated under controlled conditions, were subjected to three different concentrations of boric acid (0.05 mg/L, 0.5 mg/L, and 5 mg/L) in vitro for 96 h. Following the exposure period, the specimens were assessed for histological changes (the mantle, gill, and digestive gland) and specific oxidative parameters (the gill and digestive gland), including superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase, and lipid peroxidation (LPO). The research findings indicated that boric acid primarily induced oxidative damage at the applied concentrations and increased antioxidant levels (p < 0.05). Moreover, although no significant histopathological abnormalities were observed in the examined histological sections, subtle changes were noted. This study evaluated the potential adverse effects of boric acid on bivalves, which are crucial components of the aquatic food chain, utilizing histological and specific physiological parameters following its introduction into aquatic environments. It is anticipated that the findings of this study will contribute to the development of new insights and perspectives regarding the extensive use of boric acid.

Splenic Elemental Composition of Breast Cancer-Suffering Rats Supplemented with Pomegranate Seed Oil and Bitter Melon Extract

The aim of this study was to investigate how dietary modifications with pomegranate seed oil (PSO) and bitter melon aqueous extract (BME) affect mineral content in the spleen of rats both under normal physiological conditions and with coexisting mammary tumorigenesis. The diet of Sprague-Dawley female rats was supplemented either with PSO or with BME, or with a combination for 21 weeks. A chemical carcinogen (7,12-dimethylbenz[a]anthracene) was applied intragastrically to induce mammary tumors. In the spleen of rats, the selected elements were determined with a quadrupole mass spectrometer with inductively coupled plasma ionization (ICP-MS). ANOVA was used to evaluate differences in elemental composition among experimental groups. Multivariate statistical methods were used to discover whether some subtle dependencies exist between experimental factors and thus influence the element content. Experimental factors affected the splenic levels of macroelements, except for potassium. Both diet modification and the cancerogenic process resulted in significant changes in the content of Fe, Se, Co, Cr, Ni, Al, Sr, Pb, Cd, B, and Tl in rat spleen. Chemometric analysis revealed the greatest impact of the ongoing carcinogenic process on the mineral composition of the spleen. The obtained results may contribute to a better understanding of peripheral immune organ functioning, especially during the neoplastic process, and thus may help develop anticancer prevention and treatment strategies.

Boron compounds are effective on Tribolium castaneum (Coleoptera: Tenebrionidae): Reduced lipogenesis and induced body weight loss

In the current study, we investigated the insecticidal efficacy of two borates, disodium octaborate tetrahydrate (Etidot-67) and calcium metaborate (CMB) via surface application or diet delivery on the red flour beetle, Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae). The application method did not change the boron-related mortality, but CMB was more effective than Etidot-67. At the highest dose, it took around 13 days to reach the highest mortality (≥98.1%) for CMB, while it was 19 days for Etidot-67 (≥95.8%). Both boron compounds led to a significant reduction in triglyceride levels in parallel to the downregulation of acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), the two primary genes involved in de novo lipogenesis, while they also induced body weight loss. In conclusion, the current study indicated the insecticidal potential of boron compounds but CMB is more promising and more effective in controlling T. castaneum, while lipogenesis is inhibited and weight loss is induced by boron compounds.

Evaluation of the effect of boron derivatives on cardiac differentiation of mouse pluripotent stem cells

BACKGROUND

The heart is one of the first organs to form during embryonic development and has a very important place. So much that the formation of a functional heart is completed on the 55th day of human development and the 15th day of mouse development. Myocardial, endocardial and epicardial cells, which are derived from the mesoderm layer, are the cells that form the basis of the heart. Cardiac development, like other embryonic developments, is tightly controlled and regulated by various signaling pathways. The WNT signaling pathway is the most studied of these signaling pathways and the one with the clearest relationship with heart development. It is known that boron compounds and the Wnt/β-catenin pathway are highly correlated. Therefore, this study aimed to investigate the role of boron compounds in heart development as well as its effect on pluripotency of mouse embryonic stem cells for the first time in the literature.

METHODS

Toxicity of boron compounds was evaluated by using MTS analysis and obtained results were supported by morphological pictures, Trypan Blue staining and Annexin V staining. Additionally, the possible boron-related change in pluripotency of embryonic stem cells were analyzed with alkaline phosphatase activity and immunocytochemical staining of Oct4 protein as well as gene expression levels of pluripotency related OCT4, SOX2 and KLF4 genes. The alterations in the embryonic body formation capacity of mouse embryonic stem cells due to the application boron derivatives were also evaluated. Three linage differentiation was conducted to clarify the real impact of boron compounds on embryonic development. Lastly, cardiac differentiation of mESCs was investigated by using morphological pictures, cytosolic calcium measurement, gene expression and immunocytochemical analysis of cardiac differentiation related genes and in the presence of boron compounds.

RESULTS

Obtained results show that boron treatment maintains the pluripotency of embryonic stem cells at non-toxic concentrations. Additionally, endodermal, and mesodermal fate was found to be triggered after boron treatment. Also, initiation of cardiomyocyte differentiation by boron derivative treatments caused an increased gene expression levels of cardiac differentiation related TNNT2, Nkx2.5 and ISL-1 gene expression levels.

CONCLUSION

This study indicates that boron application, which is responsible for maintaining pluripotency of mESCs, can be used for increased cardiomyocyte differentiation of mESCs.

Boron-Containing Compounds for Prevention, Diagnosis, and Treatment of Human Metabolic Disorders

The application of natural and synthetic boron-containing compounds (BCC) in biomedical field is expanding. BCC have effects in the metabolism of living organisms. Some boron-enriched supplements are marketed as they exert effects in the bone and skeletal muscle; but also, BCC are being reported as acting on the enzymes and transporters of membrane suggesting they could modify the carbohydrate metabolism linked to some pathologies of high global burden, as an example is diabetes mellitus. Also, some recent findings are showing effects of BCC on lipid metabolism. In this review, information regarding the effects and interaction of these compounds was compiled, as well as the potential application for treating human metabolic disorders is suggested.

Exploring the mechanisms underlying the toxicity of boric acid against the land snail, Theba pisana

BACKGROUND

The land snail, Theba pisana, is one of the most important threats facing agriculture around the globe. Boric acid (BOA) is currently used as a safe alternative molluscicide to control land snails in sustainable agriculture, but the mechanisms of toxicity have not yet been investigated. The present study characterizes the lethal and sub-lethal (0.5 and 1 mg g^-1 ) toxic effects of BOA-contaminated food for 14 days by examining physiological, biochemical and histopathological indicators in T. pisana to understand the mechanisms underlying its toxic action.

RESULTS

BOA was found to be lethal against T. pisana with LC₅₀ values of 24.7 and 8.05 mg g^-1 after 3 and 7 days of exposure, respectively. BOA sublethal concentrations led to a significant reduction in food consumption and growth of snails after 14 days of exposure. BOA also caused a significant increase in testosterone levels, whereas an opposite effect was observed in estradiol levels. An increase in progesterone levels in snails in the 0.5 mg g^-1 BOA group and a decrease in the 1 mg g^-1 BOA group were observed after all exposure times. Moreover, the lipid peroxidation level and catalase activity were elevated, whereas acetylcholinesterase activity was inhibited in the treated snails. Alteration in glutathione-S-transferase activity was noticed after exposure to both sublethal concentrations. In addition, BOA induced histopathological alterations in the digestive gland of T. pisana.

CONCLUSION

Our findings provide novel insights into how physiological, biochemical and histopathological alterations can be used to explore the mechanisms underlying BOA toxicity against snails. © 2022 Society of Chemical Industry.

Boron-containing compounds on neurons: Actions and potential applications for treating neurodegenerative diseases

Boron-containing compounds (BCC) exert effects on neurons. After the expanding of both the identification and synthesis of new BCC, novel effects in living systems have been reported, many of these involving neuronal action. In this review, the actions of BCC on neurons are described; the effects have been inferred by boron deprivation or addition. Also, the effects can be related to those mediated by interaction on ionic channels, G-protein coupled receptors, or other receptors exerting modification on neuronal behavior. Additionally, BCC have exhibited effects by the modulation of inflammation or oxidative processes. BCC are expanding as drugs. Deprivation of boron sources from the diet shows the role of some natural BCC. However, the observations of several new synthesized compounds suggest their ability to act with attractive potency, efficacy, and long-term action on neuronal receptors or processes related with the origin and evolution of neurodegenerative processes. The details of BCC-target interactions are currently being elucidated in progress, as those observed from BCC-protein crystal complexes. Taking all of the above into account, the expansion is presumably near to having studies on the application of BCC as drugs on specific targets for treating neurodegenerative diseases.

Chemical Element Profiling in the Sera and Brain of Bipolar Disorders Patients and Healthy Controls

Bipolar Disorder (BD) is a severe recurrent affective mood disorder characterized by a wide range of lifelong mood swings, varying between depressive and manic states. BD affects more than 1% of the world's population irrespective of nationality, ethnic origin, or socioeconomic status and is one of the main causes of disability among young people, leading to cognitive and functional impairment and raised mortality, particularly death by suicide. Trace elements play a vital role in many biochemical and physiological processes. Compelling evidence shows that element toxicity might play a crucial role in the onset and progression of neurodegenerative disorders, but their involvement in mood disorders has been scarcely studied. In the present investigation, we determined the concentration of 26 elements in the serum of BD patients before and after treatment and in postmortem brain samples from BD patients and compared them with matched controls. The only element that was reduced significantly in the serum following treatment was vanadium (V). Furthermore, the concentration of Al, B, Cu, K, Mg and V were significantly lower in the pre-frontal cortex of BD patients compared with those of the controls. A comparison of Spearman's rank correlation coefficients between the elements in the serum and brain of BD patients and control groups pointed to boron and aluminum as being involved in the disease. These results suggest that there is a disturbance in the elements' homeostasis and the inter-elements' relationship in the brain of BD patients and advocate a thorough examination of the possible involvement of chemical elements in different stages of the disease.

Effect of Boron Supplementation on Nutrient Utilization and Productive Performance of Peripartum Murrah Buffaloes

Boron (B) has been established as a beneficial micronutrient for some farm animals. However, its impact on coping negative energy balance during transition and subsequent production performance needs critical perusal. Therefore, the present study was undertaken to determine the effect of B supplementation on productive performance, apparent nitrogen (N), and mineral utilization in peripartum Murrah buffaloes. Thirty advanced pregnant buffaloes (60 days prior to expected date of calving) were allocated into three groups, i.e. control, B-200, and B-400, and supplemented with pharmacological concentration of B at 0, 200, and 400 ppm, respectively, from 45 days prior to expected date of calving till 120 days post calving. Two metabolism trials were conducted (with animals having similar expected date of calving), one during prepartum (30 days prior to the expected date of calving) and another during postpartum (90 days post calving) phase to evaluate nutrient utilization and balance of N as well as minerals. Results revealed that B supplementation decreased (P < 0.05) overall plasma nonesterified fatty acids (NEFA), whereas plasma level of β-hydroxybutyric acid, insulin, triglyceride, and glucose did not differ (P > 0.05) among the groups. Dry matter intake, nutrient digestibility, and N balance remained unaffected with B supplementation. Higher (P < 0.05) apparent absorption coefficient for magnesium (Mg) and zinc (Zn) was observed in pregnant animals, while during lactation, absorption coefficient of calcium, Mg, and Zn was increased (P < 0.05) in B-supplemented groups. Hence, it can be concluded that alteration in NEFA concentration and variation in apparent absorption coefficient of minerals with B supplementation suggest its role in energy and mineral metabolism. However, further investigations are required to determine the underlying mechanism of action for the present findings.

Adsorptive Membrane for Boron Removal: Challenges and Future Prospects

The complexity of removing boron compounds from aqueous systems has received serious attention among researchers and inventors in the water treating industry. This is due to the higher level of boron in the aquatic ecosystem, which is caused by the geochemical background and anthropogenic factors. The gradual increase in the distribution of boron for years can become extremely toxic to humans, terrestrial organisms and aquatic organisms. Numerous methods of removing boron that have been executed so far can be classified under batch adsorption, membrane-based processes and hybrid techniques. Conventional water treatments such as coagulation, sedimentation and filtration do not significantly remove boron, and special methods would have to be installed in order to remove boron from water resources. The blockage of membrane pores by pollutants in the available membrane technologies not only decreases their performance but can make the membranes prone to fouling. Therefore, the surface-modifying flexibility in adsorptive membranes can serve as an advantage to remove boron from water resources efficiently. These membranes are attractive because of the dual advantage of adsorption/filtration mechanisms. Hence, this review is devoted to discussing the capabilities of an adsorptive membrane in removing boron. This study will mainly highlight the issues of commercially available adsorptive membranes and the drawbacks of adsorbents incorporated in single-layered adsorptive membranes. The idea of layering adsorbents to form a highly adsorptive dual-layered membrane for boron removal will be proposed. The future prospects of boron removal in terms of the progress and utilization of adsorptive membranes along with recommendations for improving the techniques will also be discussed further.

Boron Compounds Exhibit Protective Effects against Aluminum-Induced Neurotoxicity and Genotoxicity: In Vitro and In Vivo Study

Genetic, neuropathological and biochemical investigations have revealed meaningful relationships between aluminum (Al) exposure and neurotoxic and hematotoxic damage. Hence, intensive efforts are being made to minimize the harmful effects of Al. Moreover, boron compounds are used in a broad mix of industries, from cosmetics and pharmaceuticals to agriculture. They affect critical biological functions in cellular events and enzymatic reactions, as well as endocrinal and mineral metabolisms. There are limited dose-related data about boric acid (BA) and other boron compounds, including colemanite (Col), ulexite (UX) and borax (BX), which have commercial prominence. In this study, we evaluate boron compounds’ genetic, cytological, biochemical and pathological effects against aluminum chloride (AlCl₃)-induced hematotoxicity and neurotoxicity on different cell and animal model systems. First, we perform genotoxicity studies on in vivo rat bone marrow cells and peripheric human blood cultures. To analyze DNA and chromosome damage, we use single cell gel electrophoresis (SCGE or comet assay) and micronucleus (MN) and chromosome aberration (CA) assays. The nuclear division index (NDI) is used to monitor cytostasis. Second, we examine the biochemical parameters (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), total antioxidant capacity (TAC) and total oxidative status (TOS)) to determine oxidative changes in blood and brain. Next, we assess the histopathological alterations by using light and electron microscopes. Our results show that Al increases oxidative stress and genetic damage in blood and brain in vivo and in vitro studies. Al also led to severe histopathological and ultrastructural alterations in the brain. However, the boron compounds alone did not cause adverse changes based on the above-studied parameters. Moreover, these compounds exhibit different levels of beneficial effects by removing the harmful impact of Al. The antioxidant, antigenotoxic and cytoprotective effects of boron compounds against Al-induced damage indicate that boron may have a high potential for use in medical purposes in humans. In conclusion, our analysis suggests that boron compounds (especially BA, BX and UX) can be administered to subjects to prevent neurodegenerative and hematological disorders at determined doses.

Elemental Analysis of Medicinal Herb Fagonia indica Burm. f. and Its Rhizospheric Soil from Six Geographical Locations of South-eastern Sindh Province, Pakistan, During Spring and Summer Seasons

This study hypothesized that seasons and geography may affect the elemental composition of Fagonia indica. The plant was sampled along with rhizospheric soil, from six hilly geographical sites of Sindh, during March (Spring) and July (Summer) and analyzed through ICP-OES. Among 20 elements detected, the elemental concentration of rhizospheric soil was significantly affected by geography rather than seasons. The rhizospheric soil elements, Fe, Mg, Hg, K, Mn, Na, Zn, Al, were hyper-concentrated, B, Ba, Cr, Cu, Pb, Sr were moderately concentrated, and As, Cd, Ni, Rb, Ti, V were concentrated in trace levels. Contrarily, elements in Fagonia indica biomass were significantly affected by both seasons and geography. K, Na, Fe, Hg, Al, Mn, Sr, Cr, Ti, V were hyperaccumulated during summer, while Mg, Zn, As, Ba, Cd, and Cu accumulated higher during spring. PCA reveals that elements with high variances were homogenously distributed to all sites except Rohri during spring, while during summer most elements were accumulated at Johi, Dadu, Jamshoro, and Karachi. In conclusion, the plant accumulates high concentration of heavy metals during summer and higher concentration of essential nutrients during spring; therefore, its collection for oral use can be recommended during spring.

Boric acid improves the behavioral, electrophysiological and histological parameters of cisplatin-induced peripheral neuropathy in rats

Boric acid (BA) has been used in many diseases because it increases the amount of reduced glutathione in the body and reduces oxidative damage. This study aims to investigate the effects of boric acid in cisplatin-induced neuropathy, in which oxidative stress is also effective in its pathophysiology. In this study, 8-10 weeks old, 170-190 g Wistar Albino rats were used. Each group contained seven rats (n = 35). Experimental groups consist of control, sham, neuropathy, treatment, and boric acid groups. For the neuropathy model, a single dose of cisplatin (3 mg/kg, i.p) was administered once a week for five weeks, and for the treatment group, boric acid was administered daily (100 mg/kg, intragastric) for five weeks. After drug administration, the rotarod test to evaluate motor performance, the tail-flick and hot/cold plate tests to evaluate sensory conduction states, the von Frey filament test to evaluate the mechanical allodynia, and the adhesive removal test to assess sensorimotor function were performed. The sciatic nerve's motoric conduction velocity was also assessed electrophysiologically. Oxidative stress parameters were also assessed biochemically in sciatic nerve tissue and serum. Hematoxylin and eosin staining was used to evaluate the sciatic nerve tissue histopathologically. The motor conduction velocity of the sciatic nerve, impaired by cisplatin, was increased considerably by boric acid (p < 0.05). It also reduced the latency time of the compound muscle action potential (CMAP), which was increased by cisplatin. (p < 0.05). The von Frey filament test results demonstrated increased pain sensitivity of the cisplatin group increased, and mechanical allodynia was observed. Boric acid significantly alleviated this condition (p < 0.05). In the cold plate, adhesive removal, and rotarod tests, boric acid attenuated the adverse effects of cisplatin (p < 0.05). Biochemically, BA reduced the level of MDA, which was raised by cisplatin, and significantly increased the level of SOD, which was lowered by cisplatin (p < 0.05). Histopathologically; BA reduced neuronal degeneration and vacuolization caused by cisplatin. As a consequence, it has been determined that boric acid alleviates the adverse effects of cisplatin. BA reduced the destructive effect of cisplatin by reducing oxidative stress, and this effect was verified electrophysiologically, behaviorally, and histopathologically.

3-Pyridinylboronic Acid Ameliorates Rotenone-Induced Oxidative Stress Through Nrf2 Target Genes in Zebrafish Embryos

Parkinson's disease (PD) is one of the most common forms of neurodegenerative diseases and research on potential therapeutic agents for PD continues. Rotenone is a neurotoxin that can pass the blood-brain barrier and is used to generate PD models in experimental animals. Boron is a microelement necessary for neural activity in the brain. Antioxidant, non-cytotoxic, anti-genotoxic, anti-carcinogenic effects of boric acid, the salt compound of boron has been reported before. Boronic acids have been approved for treatment by FDA and are included in drug discovery studies and pyridine boronic acids are a subclass of heterocyclic boronic acids used in drug design and discovery as substituted pyridines based on crystal engineering principles. The aim of our study was to determine the effect of 3-pyridinylboronic acid in rotenone-exposed zebrafish embryos, focusing on oxidant-antioxidant parameters and gene expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes gclm, gclc, hmox1a, nqo1, and PD related genes, brain-derived neurotrophic factor, dj1, and tnfα. Zebrafish embryos were exposed to Rotenone (10 μg/l); Low Dose 3-Pyridinylboronic acid (100 μM); High Dose 3-Pyridinylboronic acid (200 μM); Rotenone + Low Dose-3-Pyridinylboronic acid (10 μg/l + 100 μM); Rotenone + High Dose-3-Pyridinylboronic acid (10 μg/l + 200 μM) in well plates for 96 h post-fertilization (hpf). Our study showed for the first time that 3-pyridinylboronic acid, as a novel sub-class of the heterocyclic boronic acid compound, improved locomotor activities, ameliorated oxidant-antioxidant status by decreasing LPO and NO levels, and normalized the expressions of bdnf, dj1, tnf⍺ and Nrf2 target genes hmox1a and nqo1 in rotenone exposed zebrafish embryos. On the other hand, it caused the deterioration of the oxidant-antioxidant balance in the control group through increased lipid peroxidation, nitric oxide levels, and decreased antioxidant enzymes. We believe that these results should be interpreted in the context of the dose-toxicity and benefit-harm relationship of the effects of 3-pyridinylboronic.

Diversity of effects induced by boron-containing compounds on immune response cells and on antibodies in basal state

BACKGROUND

It has been reported that boron induces changes in the immune response, including in inflammatory processes. Recently, the effect of boric acid has been documented on the differentiation of lymphocyte clusters in mice and rats. However, the differences among boron-containing compounds (BCC) have been poorly explored.

METHODS

In this study, we analyzed the effects after oral administration of boric acid (BOR), methylboronic (MET), 3-thyenylboronic (3TB), 4-hydroxymethyl-phenylboronic (4MP) and 4-methanesulfonyl-phenylboronic (4SP) acids on the populations of lymphocytes from spleen and Peyer's patch (PP) as well as on antibodies. Groups of six male BALB/c were orally treated with 4.6 mg/kg of body weight with BOR, MET, 3TB, 4MP, and 4SP/daily for 10 days or vehicle (VEH) as a control group. After euthanasia, the spleen and small intestine were dissected. We conducted flow cytometry assays to assess B, CD3⁺ T, CD4⁺ T, and CD8⁺ T cells. Levels of IgG and IgM in serum, and IgA in intestinal fluid samples were analyzed by enzyme immunoassay.

RESULTS

In particular, we observed the effects of the administration of boronic acids on the number of lymphocytes; these changes were more notable in spleen than in PP. We found different profiles for each boron-containing compound, that is BOR induced an increase in the percentage of CD8⁺ T and CD19⁺/IgA⁺ cells in spleen, but a decrease in CD8⁺ T and B220⁺/CD19⁺ cells in PP. Meanwhile MET induced a decrease of CD4⁺ T in spleen, but induced an increase of CD4⁺ T cells and a decrease in the number of CD8⁺ T cells in PP. Boronic acids with an aromatic ring moiety induced changes in serum immunoglobulins levels, while 3TB acid induced a notable increase in S-IgA.

CONCLUSIONS

Effects in lymphocyte populations and antibodies are different for each tested compound. These results highlight the establishment of the necessary structure-activity relationship for BCC as immunomodulatory drugs. This is relevant in the biomedical field due to their attractiveness for selecting compounds to develop therapeutic tools.

A non-invasive assessment of essential trace element utilization at different trophic levels in African wildlife

The complex relationships that exist between terrestrial mammals and their habitats make African ecosystems highly interactive environments. Anthropogenic activities including climate change have altered geochemical cycles, which influence nutrient availability and deficiency at local, regional and global scales. As synergistic and antagonistic interactions occur between essential elements at both deficiency and excess concentrations, the differences in feeding strategy between trophically distinct groups of terrestrial vertebrates are likely to influence the degree to which overall nutrient needs are met or may be deficient. The overall aim of this study was to investigate and compare quantitative differences of nine essential elements in terrestrial vertebrates occupying different trophic levels within two protected areas; Tswalu Kalahari Reserve (TKR) and Manyeleti Nature Reserve (MNR) South Africa, using faeces as an analytical matrix. Results from linear mixed effects models highlight that concentrations varied widely between individuals. Overall, measured concentrations above their respective means were evident for B and Mn in herbivores, Fe in omnivores and Cu, Co, Fe, Se and Zn in carnivores. Measured concentrations of Mo and Ni did not differ significantly between trophic groups. Although site-specific differences were evident for specific elements, measured mean concentrations of B, Co, Cu, Fe, Mo, Ni, Se and Zn were significantly higher overall at the MNR study site compared to the TKR site. This is the first study to non-invasively assess essential element concentrations across trophic levels in free ranging African wildlife species within protected areas of the savannah biome. Combined with the assessment of environmental matrices, this approach can be used as an effective diagnostic tool for the assessment of animal welfare and the management of protected areas globally.

Environmental Hazards of Boron and Vanadium Nanoparticles in the Terrestrial Ecosystem-A Case Study with Enchytraeus crypticus

From the start of the 21st century, nanoecotoxicological research has been growing in fast steps due to the need to evaluate the safety of the increasing use of engineered nanomaterials. Boron (B) and vanadium (V) nanoparticles (NPs) generated by anthropogenic activities are subsequently released in the environment; therefore, organisms can be continuously exposed to these NPs for short or long periods. However, the short and long-term effects of BNPs and VNPs on soil organisms are unknown. This work aimed to recognize and describe their potential toxicological effects on the model species Enchytraeus crypticus, assessing survival and reproduction, through a longer-term exposure (56 days (d)-OECD test extension of 28 d), and avoidance behavior, through a short-term exposure (48 hours (h)). After 28 d, BNPs did not induce a significant effect on E. crypticus survival, whereas they decreased the organisms' reproduction at 500 mg/kg. From 10 to 500 mg/kg, VNPs decreased the E. crypticus survival and/or reproduction. After 56 d, 100 to 500 mg/kg BNPs and 50 to 500 mg/kg VNPs, decreased the reproduction output of E. crypticus. The estimated Effect Concentrations (EC_x) based on reproduction, for BNPs, were lower at 56 d compared with 28 d; for VNPs, an opposite pattern was found: EC_x 28 d < EC_x 56 d. BNPs did not induce an avoidance behavior, but organisms avoided the soil contaminated with 10 mg VNPs/kg. The tested NPs showed different E. crypticus apical effects at 28 d from the ones detected at 56 d, dependent on the type of NPs (B vs. V). In general, VNPs showed to be more toxic than BNPs. However, the effects of VNPs were alleviated during the time of exposure, contrarily to BNPs (which became more toxic with extended duration). The present study adds important information about NPs toxicity with ecological significance (at the population level). Including long-term effects, the obtained results contributes to the improvement of NPs risk assessment.

Moderate dietary boron supplementation improved growth performance, crude protein digestibility and diarrhea index in weaner pigs regardless to the sanitary condition

Objective

The study was conducted to investigate the impact of boron supplementation on nutrient digestibility, inflammatory responses, blood metabolites and diarrhea index, and their relevance to growth performance in weaned pigs housed in good and poor sanitary environments for 14 days after weaning.

Methods

A total of 108 male pigs (Duroc×[Yorkshire×Landrace]) weaned at 21 days of age were used in a randomized complete block design with 2×3 factorial arrangement. Pigs were assigned to three boron treatments (0, 5, and 10 mg/kg) under two environments (good and poor sanitary) to give six replicates per treatment (3 pigs per replicate). On 0, 7, and 14 days, one pig per replicate was euthanized to collect, ileum tissue samples, and rectal fecal samples.

Results

Boron supplementation quadratically influenced (p<0.001) feed intake and weight gain in pigs housed in good sanitary conditions from 1 to 14 days post-weaning where pigs offered 5 mg/kg boron optimized weight gain and feed intake. There is a quadratic interaction (p = 0.019) on feed intake for 1 to 14 days post-weaning where 5 mg/kg boron increased feed intake in good sanitary conditions. Pigs housed in the poor sanitary environment decreased (p<0.001) villus height and crypt depth in ileum at days 7 and 14. On day 7 and 14, crude protein digestibility was quadratically influenced (p<0.05) by boron supplementation. Boron supplementation linearly increased (p<0.05) plasma calcium and cholesterol levels whilst linearly (p = 0.005) reducing plasma triglyceride concentrations. Diarrhea index was quadratically influenced (p<0.05) by boron supplementations regardless of sanitary conditions where 5 mg/kg boron inclusion achieved the lowest diarrhea index.

Conclusion

Pigs offered 5 mg/kg of boron increased weight gain which may be deduced by improved dry matter, crude protein, and energy digestibility regardless of the sanitary conditions.

Assessment of consumer exposure to boron in cleaning products: a case study of Canada

Boron is an essential mineral for plants, and as such, is a normal dietary constituent for humans. Humans may be naturally exposed to boron through food and drinking water, or via anthropogenic sources such as consumer products. The World Health Organisation established an acceptable safe range of population mean intakes for boron of 1-13 mg/day. Most studies of dietary boron intake show a range of 1-2 mg/day. Consumer products have been estimated to contribute a geometric mean daily intake of 0.1 mg to total boron exposure; however, there are few published surveys of consumer exposure to boron from use of cleaning products. The Government of Canada published a draft screening assessment report of boric acid, its salts and precursors that included estimates of consumer exposure to boron found as ingredients in consumer products. The manufacturers of consumer cleaning products conducted a survey of boron content of current products and estimated exposure using the publicly available exposure tool ConsExpo Web. Dermal exposures to boron during cleaning product use were estimated to result in annual internal exposures ranging from ≪0.001 to 0.36 μg/kg bw/day based on dermal absorption of 0.5%. Using a conservative point of departure for hazard assessment (2,900 μg boron/kg bw/day), estimated margins of exposure for dermal exposures to boron from cleaning product use range from 8,056 to >1,000,000. This work demonstrates that exposure to boron from cleaning product use is very low and essentially insignificant when compared to other (e.g. dietary) sources of boron intake by Canadian consumers.

Effects of boron-containing compounds in the fungal kingdom

BACKGROUND

The number of known boron-containing compounds (BCCs) is increasing due to their identification in nature and innovative synthesis procedures. Their effects on the fungal kingdom are interesting, and some of their mechanisms of action have recently been elucidated.

METHODS

In this review, scientific reports from relevant chemistry and biomedical databases were collected and analyzed.

RESULTS

It is notable that several BCC actions in fungi induce social and economic benefits for humans. In fact, boric acid was traditionally used for multiple purposes, but some novel synthetic BCCs are effective antifungal agents, particularly in their action against pathogen species, and some were recently approved for use in humans. Moreover, most reports testing BCCs in fungal species suggest a limiting effect of these compounds on some vital reactions.

CONCLUSIONS

New BCCs have been synthesized and tested for innovative technological and biomedical emerging applications, and new interest is developing for discovering new strategic compounds that can act as environmental or wood protectors, as well as antimycotic agents that let us improve food acquisition and control some human infections.

Effects of boric acid supplementation on bone health in crossbred calves under tropical condition

INTRODUCTION

Boron (B) is thought to play key role in proper bone growth and development as well as have some role in regulation of minerals such as calcium (Ca), phosphorus (P) and magnesium (Mg) which act synergistically with vitamin D.

OBJECTIVE

Present study was planned in two phases to assess the effect of optimum and supranutritional levels of (B) in the form of boric acid (BA) supplementation on bone health of growing cross bred calves.

METHOD

During Phase-1, twenty four male crossbred calves were blocked into four groups (n = 6) on the basis of their body weight (154.83 ± 8.5 kg), age (7-9 months) and were supplemented with 0 (C), 2.6 (T-1), 5.4 (T-2) and 10.7 (T-3) g BA for appropriate B (0.175 adjustment factor to calculate B form BA) consumption i.e. 0, 100, 200 and 400 ppm in each group respectively, for 90 days. During phase 2, twenty-one male crossbred calves were divided into 3 groups (n = 7) on the basis of their body weight (103.76 ± 4.34 kg) and age (5-8 months). All the groups were on similar dietary regimen with additional supplementation of boric acid as 0 g (control); 3.6 g (200 ppm B; T-1) and 10.8 g (600 ppm B; T-2), respectively for a period of 120 d.

RESULTS

From the first experiment it is reported that plasma levels of bovine alkaline phosphatase (BALP), type I collagen cross-linked N-telopeptide (NTx) and Ca were significantly (P < 0.05) affected in T-2 and T-3 groups as compared to T-1 and control groups. Whereas, plasma osteocalcin (OCN) concentration was found to be higher in T-2 and T-3 groups as compared to control group. However, plasma concentrations (ng/mL) of tartrate resistant acid phosphatase (TRAP) remained unaltered due to dietary treatments. Based on the results, another experiment was conducted to validate the above findings and further to determine the effect of still higher i.e supranutritional levels of BA supplementation on bone health of calves. Results revealed that supplementation of BA in T-2 group had no beneficial effect on bone health as the plasma concentration of BALP, OCN, NTx, 25 (OH) vitamin D and Ca as compared to T-1 group in phase 2. Other possible attributes of bone health i.e. plasma concentration of Mg, P, parathyroid hormone (PTH), and calcitonin were not affected by BA supplementation at any levels.

CONCLUSION

Overall from present study it can be concluded that supplementation of boric acid 3.6 g/d (equivalent to 200 ppm B) in the diet of growing animals has positive effect on bone health related biomarkers (OCN, NTx and BALP) and supplementation of supranutritional level of BA i.e. 10.8 g (equivalent to 600 ppm B) level had neither additional beneficial nor harmful effect on bone health of calves.

High Content of Boron in Curative Water: From the Spa to Industrial Recovery of Borates? (Poland as a Case Study)

Boron minerals are a sought-after raw material. The European Union’s total dependence on imported borates means that this has been a critical material since 2014. Due to the increased use of borates in modern economies, data on the predicted boron demand in the coming years indicate that it may become a critical element on a global scale. Formerly, the high boron content in groundwater was the basis for qualifying it as medicinal water (boric water). Nevertheless, the current information on the potential toxicity of boron and the narrow margin between deficiency and toxicity of boron in the human body has caused a tightening of the limits of this element in water intended for human consumption. For this reason, metaboric acid has lost its position as a specific component of curative waters. However, despite the fact that boron is not currently a specific component of curative waters, it is found in measureable concentrations in Polish medicinal water considered therapeutic based on other valuable specific components. High boron content in curative water may be the cause of the problems in some spas when obtaining certificates confirming the therapeutic properties of waters. Literature data indicate that waters with high boron content (above 25 mg/L) should not be freely available for drinking in pump rooms and other places in health resorts. To identify the situation with Polish health resorts, the content of boron in 248 curative water samples was analyzed. In 154 of these samples, the boron concentration was relatively low and did not exceed 5 mg/L. However, in the remaining 94 samples, the boron content exceeded 5 mg/L, and 38 samples had boron content exceeding 30 mg/L. Ten of the 248 samples of curative water had a boron concentration above 100 mg/L, which may be a potential source of boron for industrial recovery. The highest concentration of boron was noticed in a water sample from the Wysowa health resort and was 187.6 mg/L. Unfortunately, most of water intakes with a high concentration of boron (above 100 mg/L) are low-yielding wells. Based on the data collected, Rabka appears to be the best candidate for small-scale boron production in terms of boron content and water resources values.

Pivotal role of boron supplementation on bone health: A narrative review

BACKGROUND

Boron is a trace element that plays an important role in numerous biological functions, including calcium metabolism, growth and maintenance of bone tissue. However, there are still no precise indications regarding a possible role of boron supplementation, and its amount of supplementation, to maintain bone health. So the aim of this narrative review was to consider the state of the art on the effectiveness of boron supplementation (alone or with other micronutrients) on growth and maintenance of bone in humans through control of calcium, vitamin D and sex steroid hormone metabolism in order to suggest a daily dosage of boron supplementation.

MAIN FINDINGS

This review included 11 eligible studies: 7 regarding the supplementation with boron alone and 4 regarding supplementation with boron and other nutrients. Despite the number of studies considered being low, the number of subjects studied is high (594) and the results are interesting.

CONCLUSIONS

The studies considered in this narrative review have evaluated the positive effectiveness on bone, in humans, through control of calcium, vitamin D and sex steroid hormone metabolism, considering a dietary supplementation of 3 mg/day of boron (alone or with other nutrients); this supplementation is demonstrably useful to support bone health (in order to prevent and maintain adequate bone mineral density), also considering the daily dose of 3 mg is much lower than the Upper Level indicated by EFSA in the daily dose of 10 mg.

Role of sodium tetraborate as a cardioprotective or competitive agent: Modulation of hypertrophic intracellular signals

Boron is an essential trace element in cellular metabolism; however, the molecular mechanism of boron in the heart is unclear. In this study, we examined the effect of sodium tetraborate (as boron source) as a possible protective agent or competitive inhibitor of cardiac hypertrophy in an in vitro murine model. We evaluated different previously reported sodium tetraborate concentrations and it was found that 13 μM improves viability without affecting the cellular structure. We demonstrated that cardiomyocytes pretreated with sodium tetraborate prevents cellular damage induced by isoproterenol (cardioprotective effect) by increasing proliferation rate and inhibiting apoptosis. In addition, the reduction of the expression of the α1AR and β1AR adrenergic receptors as well as Erk1/2 was notable. Consequently, the expression of the early response genes c-myc, c-fos and c-jun was delayed. Also, the expression of GATA-4, NFAT, NKx2.5 and myogenin transcription factors involved in sarcomere synthesis declined. In contrast, cardiomyocytes, when treated simultaneously with sodium tetraborate and isoproterenol, did not increase their size (cytoplasmic gain), but an increase in apoptosis levels was observed; therefore, the proliferation rate was reduced. Although the mRNA levels of α1AR and β1AR as well as Erk1/2 and Akt1 were low at 24 h, their expression increased to 48 h. Notably, the mRNA of expression levels of c-myc, c-fos and c-jun were lower than those determined in the control, while the transcription factors GATA-4, MEF2c, Nkx2.5, NFAT and CDk9 were determined in most cells. These results suggest that pretreatment with sodium tetraborate in cardiomyocytes inhibits the hypertrophic effect. However, sodium tetraborate attenuates isoproterenol induced hypertrophy damage in cardiomyocytes when these two compounds are added simultaneously.

3-Pyridinylboronic acid normalizes the effects of 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine exposure in zebrafish embryos

1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that damages dopaminergic neurons. Zebrafish has been shown to be a suitable model organism to investigate the molecular pathways in the pathogenesis of Parkinson's disease and also for potential therapeutic agent research. Boron has been shown to play an important role in the neural activity of the brain. Boronic acids are used in combinatorial approaches in drug design and discovery. The effect of 3-pyridinylboronic acid which is an important sub-class of heterocyclic boronic acids has not been evaluated in case of MPTP exposure in zebrafish embryos. Accordingly, this study was designed to investigate the effects of 3-pyridinylboronic acid on MPTP exposed zebrafish embryos focusing on the molecular pathways related to neurodegeneration and apoptosis by RT-PCR. Zebrafish embryos were exposed to MPTP (800 μM); MPTP + Low Dose 3-Pyridinylboronic acid (50 μM) (MPTP + LB) and MPTP + High Dose 3-Pyridinylboronic acid (100 μM) (MPTP + HB) in well plates for 72 hours post fertilization. Results of our study showed that MPTP induced a P53 dependent and Bax mediated apoptosis in zebrafish embryos and 3-pyridinylboronic acid restored the locomotor activity and gene expressions related to mitochondrial dysfunction and oxidative stress due to the deleterious effects of MPTP, in a dose-dependent manner.