Borax attenuates oxidative stress, inflammation, and apoptosis by modulating Nrf2/ROS balance in acrylamide-induced neurotoxicity in rainbow trout

Acrylamide (ACR) can have adverse environmental effects because of its multiple applications. Relevant scientific literatures of the existence of ACR residues in foods following processing steps have raised concern in the biochemistry, chemistry and safety of this vinyl substance. The interest has focused on the hepatotoxicity of ACR in animals and humans and on the ACR content mitigation and its detoxification. Borax (BX), as a naturally occurring antioxidant featured boron compound, was selected in this investigation to assess its possible neuro-protective potential against ACR-induced neurotoxicity. Nrf2 axis signaling pathways and detoxification response to oxidative stress after exposure to ACR in brains of rainbow trout, and the effect of BX application on reducing ACR-induced neurotoxicity were investigated. Rainbow trout were acutely exposed to ACR (12.5 mg/L) alone or simultaneously treated with BX (0.75 mg/L) during 96h. The exposed fish were sampled at 48th and 96th and oxidative stress response endpoints, 8-OHdG, Nrf2, TNF-α, caspase-3, in addition to IL-6 activities and the levels of AChE and BDNF in brain tissues of rainbow trout (Oncorhynchus mykiss) were evaluated. Samples showed decreases in the levels of ACR-mediated biomarkers used to assess neural toxicity (SOD, CAT, GPx, AChE, BDNF, GSH), increased levels of MDA, MPO, DNA damage and apoptosis. ACR disrupted the Nrf2 pathway, and induced neurotoxicity. Inhibited activities' expressions under simultaneous administration experiments, revealed the protective effects of BX against ACR-induced toxicity damage. The obtained data allow the outline of early multi-parameter signaling pathways in rainbow trout.

Therapeutic role of boron on acrylamide-induced nephrotoxicity, cardiotoxicity, neurotoxicity, and testicular toxicity in rats: Effects on Nrf2/Keap-1 signaling pathway and oxidative stress

BACKGROUND

Acrylamide (ACR) is a heat-related carcinogen used in cooking some foods as well as in other thermal treatments. The present study aims to investigate the possible protective effect of boron (BA) against ACR-induced toxicity of kidney, brain, heart, testis, and bladder tissues in rats.

METHODS

Rats have been divided into 5 equal groups: Control (saline), ACR (38.27 mg/kg), BA (20 mg/kg), BA+ ACR (10 mg/kg + ACR), and BA+ ACR (20 mg/kg BA+ACR). Kidney tissue from rats was collected and the levels of malondialdehyde (MDA), glutathione (GSH), and the activity of superoxide dismutase (SOD) were measured. In addition, the kidneys of these animals, as well as the brain, heart, testes, and bladder tissues were examined for possible histological changes. Total Nrf2 and Keap-1 protein expression in kidney, heart, and testis tissues was examined by immunohistochemistry.

RESULTS

While significant increases in MDA levels were observed in the kidneys of rats receiving ACR alone, significant decreases in antioxidant markers (SOD and GSH) were observed. Besides, kidney, brain, heart, and testicular tissues were analyzed and damage was observed in the groups receiving ACR. However, no significant histologic changes were noted in the bladder tissue. Both dosages of BA in combination with ACR improved the changes in ACR-induced antioxidant tissue parameters. Despite the fact that MDA levels were decreased with these two dosages, histological structural abnormalities were found to be greatly improved.

CONCLUSION

Our results show that BA has a strong protective effect on ACR-induced multi-organ toxicity. The study results show that BA could be a potential element to reduce ACR toxicity to which we are often exposed.

Acetaminophen-Induced Nephrotoxicity: Suppression of Apoptosis and Endoplasmic Reticulum Stress Using Boric Acid

Acetaminophen (APAP) is one of the popular and safe pain medications worldwide. However, due its wide availability, it is frequently implicated in intentional or unintentional overdoses where it can cause severe liver injury and even acute liver failure. Boron is a bioactive trace element, found naturally as boric acid (BA) and borate. In this study, the effects of boric acid on the acute renal toxicity induced by APAP in rats were researched in comparison with N-acetyl cysteine (NAC). In the study, 7 groups were formed and 2 g/kg dose of paracetamol per rat was prepared by suspending in 1% Carboxy Methyl Cellulose (CMC) solution of phosphate buffer saline (PBS). Boric acid dissolved in saline was administered to experimental animals by gavage at doses of 50, 100, and 200 mg/kg. In this study, ER stress and apoptosis formed by paracetamol-induced nephrotoxicity were investigated. This purpose determined iNOS, PERK, ATF6, NFkB p53, caspases 3, 12, bcl-2, and bcl-xL gene mRNA expression kidney tissue. Also, the levels of kidney injury molecule-1 (KIM-1), Cysteine (Cys), and IL-18 levels, which are mentioned today as kidney damage markers were compared with BUN and creatine levels. The effect of boron on kidney damage was determined by histopathologic. Data were statistically analyzed by using SPSS-20 ANOVA and stated as means and standard deviation. According to the data obtained in our study, we believe that boric acid has a protective effect on the negative effects of paracetamol on the kidney. We believe that our study will provide useful data to the literature on the possibility of a supplement to be used as an active compound in paracetamol for the prophylaxis of boric acid and it can also be converted into a useful product.

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.

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.

Inflammation and Alzheimer's Disease: Mechanisms and Therapeutic Implications by Natural Products

Alzheimer's disease (AD) is a neurodegenerative disorder with no clear causative event making the disease difficult to diagnose and treat. The pathological hallmarks of AD include amyloid plaques, neurofibrillary tangles, and widespread neuronal loss. Amyloid-beta has been extensively studied and targeted to develop an effective disease-modifying therapy, but the success rate in clinical practice is minimal. Recently, neuroinflammation has been focused on as the event in AD progression to be targeted for therapies. Various mechanistic pathways including cytokines and chemokines, complement system, oxidative stress, and cyclooxygenase pathways are linked to neuroinflammation in the AD brain. Many cells including microglia, astrocytes, and oligodendrocytes work together to protect the brain from injury. This review is focused to better understand the AD inflammatory and immunoregulatory processes to develop novel anti-inflammatory drugs to slow down the progression of AD.

Dietary inclusions of Solanum vegetables mitigate aluminum-induced redox and inflammation-related neurotoxicity in Drosophila melanogaster model

BACKGROUND

This study investigated the modulatory capacity of two Solanum green leafy vegetables; S. macrocarpon L. (African eggplant AE) and S. nigrum L. (Black nightshade BN) on dysregulation of some antioxidant, pro-apoptotic, pro-inflammatory-like, acetylcholinesterase gene expression and redox status in the Drosophila melanogaster model of aluminum-induced neurotoxicity.

METHODS

Flies were exposed to AlCl₃ (6.7 mM) alone or in combination with the leaves (0.1 and 1.0%) from both samples in their diet for seven days. Thereafter, the fly heads were rapidly separated, homogenized, and used to assay for reactive oxygen species (ROS), total thiol content, catalase, glutathione-S-transferase (GST), acetylcholinesterase (AChE) activities, and the expression of antioxidant-mediators (Hsp70, catalase, cnc/Nrf2, Jafrac1 and FOXO), acetylcholinesterase (Ace1), pro-apoptotic caspase-like (Dronc) and its regulator (reaper), as well as inflammation-related (NF-kB/Relish) genes.

RESULTS

Results showed that AlCl₃-exposed flies had significantly reduced survival rate which were ameliorated by AlCl₃ also elevated ROS, GST and reduced AChE activities in fly heads while dietary inclusions of AE and BN ameliorated survial rate and oxidative stress in AlCl₃-exposed flies. In addition, Hsp70, Jafrac1, reaper and NF-kҝB/Relish were significantly upregulated in AlCl₃-exposed fly heads, while cnc/Nrf2 and FOXO were significantly downregulated, but catalase, Dronc and Ace were, not significantly modulated. Nevertheless, these impairments in gene expression levels were ameliorated by dietary inclusions of AE and BN during AlCl₃ exposure.

CONCLUSION

These findings showed that dietary inclusions of AE and BN leaves offer protection against Al-induced neurotoxicity in D. melanogaster and thus, could serve as functional foods with neuroprotective properties.

Chenodeoxycholic Acid Ameliorates AlCl3-Induced Alzheimer's Disease Neurotoxicity and Cognitive Deterioration via Enhanced Insulin Signaling in Rats

Insulin resistance is a major risk factor for Alzheimer’s disease (AD). Chenodeoxycholic acid (CDCA) and synthetic Farnesoid X receptor (FXR) ligands have shown promising outcomes in ameliorating insulin resistance associated with various medical conditions. This study aimed to investigate whether CDCA treatment has any potential in AD management through improving insulin signaling. Adult male Wistar rats were randomly allocated into three groups and treated for six consecutive weeks; control (vehicle), AD-model (AlCl₃ 50 mg/kg/day i.p) and CDCA-treated group (AlCl₃ + CDCA 90 mg/kg/day p.o from day 15). CDCA improved cognition as assessed by Morris Water Maze and Y-maze tests and preserved normal histological features. Moreover, CDCA lowered hippocampal beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) and amyloid-beta 42 (Aβ₄₂). Although no significant difference was observed in hippocampal insulin level, CDCA reduced insulin receptor substrate-1 phosphorylation at serine-307 (pSer307-IRS1), while increased protein kinase B (Akt) activation, glucose transporter type 4 (GLUT4), peroxisome proliferator-activated receptor gamma (PPARγ) and glucagon-like peptide-1 (GLP-1). Additionally, CDCA activated cAMP response element-binding protein (CREB) and enhanced brain-derived neurotrophic factor (BDNF). Ultimately, CDCA was able to improve insulin sensitivity in the hippocampi of AlCl₃-treated rats, which highlights its potential in AD management.

Effects of boron-containing compounds on immune responses: review and patenting trends

INTRODUCTION

Boron-containing compounds induce effects on immune responses. Such effects are interesting to the biomedical field for the development of therapeutic tools to modulate the immune system.

AREAS COVERED

The scope of BCC use to modify immune responses is expanding, mainly with regard to inflammatory diseases. The information was organized to demonstrate the breadth of reported effects. BCCs act as modulators of innate and adaptive immunity, with the former including regulation of cluster differentiation and cytokine production. In addition, BCCs exert effects on inflammation induced by infectious and noninfectious agents, and there are also reports regarding their effects on mechanisms involving hypersensitivity and transplants. Finally, the authors discuss the beneficial effects of BCCs on pathologies involving various targets and mechanisms.

EXPERT OPINION

Some BCCs are currently used as drugs in humans. The mechanisms by which these BCCs modulate immune responses, as well as the required structure-activity relationship for each observed mechanism of action, should be clarified. The former will allow for the development of improved immunomodulatory drugs with extensive applications in medicine. Patenting trends involve claims concerning the synthesis and actions of identified molecules with a defined profile regarding cytokines, cell differentiation, proliferation, and antibody production.

Turning fear of boron toxicity into boron-containing drug design

BACKGROUND

Despite the historical employment of boron-containing compounds (BCCs) with medicinal purposes, the reported cases of BCC toxicity in humans during the twentieth century were driving us towards an "boron-withdrawal" period. Fortunately, the use of boric acid for specific purposes remains, and the discovery of natural BCCs with biological action attractive for therapeutic purposes as well as the introduction of some new BCCs for clinical use have reactivated the interest in studying the properties of these BCCs.

METHODS

We carried out a structured search of bibliographic databases for scientific peer-reviewed research literature regarding boron toxicity and linked that information to that about BCCs in drug design and development. A deductive qualitative content analysis methodology was applied to analyse the interventions and findings of the included studies using a theoretical outline.

RESULTS

This review recapitulates the following on a timeline: the boron uses in medicine, the data known about the toxicological profiles of some BCCs, the pharmacological properties of some BCCs that are employed in cancer and infectious disease therapies, and the known properties of BCCs recently introduced into clinical assays as well as the identification of their structure-activity relationships for toxicity and therapeutic use. Then, we discuss the use of new approaches taking advantage of some toxicological data to identify potent and efficient BCCs for prevention and therapy while limiting their toxic effects.

CONCLUSION

Data for boron toxicity can be strategically used for boron-containing drug design.

BORON PREPARATIONS IN PSYCHIATRY AND NEUROLOGY: THEIR RISE, FALL AND RENEWED INTEREST

The use of boron preparations (borax and boric acid) in medicine began long before their isolation in pure form. The mineral water of  boron-containing sources has been historically used to treat skin  diseases, to wash eyes, to disinfect wounds, etc. Also, what is of  interest in the context of this article, boron-containing waters were  used as calming, anti- anxiety, anticonvulsant and sleep-promoting  remedy. In 1777, boric acid was first isolated from the mineral water of a healing spring source in Florence. Historically, first name  of this compound was sal sedativum (“soothing salt”). However, the  discovery of boron toxicity led to the cessation of its internal use. In  recent decades, it has been found that boron is a microelement  necessary for many metabolic processes in the body. It affects  memory, cognitive functions, anxiety level, sleep, mood, regulates  calcium and magnesium exchange, metabolism of vitamin D and sex  steroids. It has been shown that some cases of treatment  resistance to standard therapy, for example in epilepsy, anxiety and depression, are related to boron deficiency. In this regard,  interest in the use of boron preparations in psychiatry and neurology, but in much smaller doses and on new scientific grounds, flared up again.

Boric acid reduces axonal and myelin damage in experimental sciatic nerve injury

The aim of this study was to investigate the effects of boric acid in experimental acute sciatic nerve injury. Twenty-eight adult male rats were randomly divided into four equal groups (n = 7): control (C), boric acid (BA), sciatic nerve injury (I), and sciatic nerve injury + boric acid treatment (BAI). Sciatic nerve injury was generated using a Yasargil aneurysm clip in the groups I and BAI. Boric acid was given four times at 100 mg/kg to rats in the groups BA and BAI after injury (by gavage at 0, 24, 48 and 72 hours) but no injury was made in the group BA. In vivo electrophysiological tests were performed at the end of the day 4 and sciatic nerve tissue samples were taken for histopathological examination. The amplitude of compound action potential, the nerve conduction velocity and the number of axons were significantly lower and the myelin structure was found to be broken in group I compared with those in groups C and BA. However, the amplitude of the compound action potential, the nerve conduction velocity and the number of axons were significantly greater in group BAI than in group I. Moreover, myelin injury was significantly milder and the intensity of nuclear factor kappa B immunostaining was significantly weaker in group BAI than in group I. The results of this study show that administration of boric acid at 100 mg/kg after sciatic nerve injury in rats markedly reduces myelin and axonal injury and improves the electrophysiological function of injured sciatic nerve possibly through alleviating oxidative stress reactions.

The in vitro protective effect of salicylic acid against paclitaxel and cisplatin-induced neurotoxicity

Paclitaxel (PAC) and cisplatin (CIS) are two established chemotherapeutic drugs used in combination for the treatment of various solid tumors. However, the usage of PAC and CIS are limited because of the incidence of their moderate or severe neurotoxic side effects. In this study, we aimed to assess the protective role of salicylic acid (SA) against neurotoxicity caused by PAC and CIS. For this purpose, newborn Sprague Dawley rats were decapitated in sterile atmosphere and primary cortex neuron cultures were established. On the 10th day SA was added into culture plates. PAC and CIS were added on the 12th day. The cytotoxicity was determined by using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Oxidative alterations were assessed using total antioxidant capacity and total oxidative stress assays in rat primary neuron cell cultures. It was shown that both concentrations of PAC and CIS treatments caused neurotoxicity. Although SA decreased the neurotoxicity by CIS and PAC, it was more effective against the toxicity caused by CIS rather than the toxicity caused by PAC. In conclusion it was clearly revealed that SA decreased the neurotoxic effect of CIS and PAC in vitro.

Cytogenetic and oxidative alterations after exposure of cultured human whole blood cells to lithium metaborate dehydrate

Boron compounds have an ability of supporting antioxidant properties in human and animal tissues. Lithium metaborate dihydrate (LiBO2·2H2O; LMD) is commonly used in nonlinear optic materials, cellular phones and pagers. But, there are limited data on the genotoxic and antioxidant effects of LMD in cultured human whole blood cells. The aim of this study was to evaluate for the genotoxicity and antioxidant/oxidant activity of LMD on human whole blood lymphocytes (n = 5). LMD was applied at various concentrations (0-1,280 µg/ml) to cultured blood samples. Antioxidant/oxidant activity was evaluated by measuring the total oxidant status (TOS) and total antioxidant capacity levels. Micronuclei and chromosomal aberration tests were used in genotoxicity studies. Our results clearly revealed that all tested concentrations of LMD were found to be non-genotoxic when compared to that of the control group. In addition, LMD exhibited antioxidant activities at low concentrations. In addition the TOS levels were not changed at all concentrations of LMD. Consequently, our results clearly demonstrated that LMD is non-genotoxic and it has an important antioxidant potential in vitro.

Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

Abstract Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007) . Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of "total Al"assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al(+3) to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)(+2) and Al(H2O)6 (+3)] that after complexation with O2(•-), generate Al superoxides [Al(O2(•))](H2O5)](+2). Semireduced AlO2(•) radicals deplete mitochondrial Fe and promote generation of H2O2, O2 (•-) and OH(•). Thus, it is the Al(+3)-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer's disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances.

Evaluating the potential role of pomegranate peel in aluminum-induced oxidative stress and histopathological alterations in brain of female rats

Studies have shown that pomegranate, Punica granatum Linn. (Lythraceae), has remarkable biological and medicinal properties. However, the effects of pomegranate peel methanolic extract (PPME) on the aluminum-induced oxidative stress and histopathological change have not been reported yet. To determine the effect of PPME (200 mg/kg bwt) on the aluminum chloride (AlCl₃; 34 mg/kg bwt)-induced neurotoxicity, aluminum accumulation in brain and oxidant/antioxidant status were determined. The change of brain structure was investigated with hematoxylin and eosin, and anti-apoptosis effects of PPME were analyzed by immunohistochemistry. The present study showed an indication of carcinogenicity in the AlCl₃-treated group representing an increase in tissue tumor markers such as tumor necrosis factor-α and angiogenin and inflammation by inducing an increase in prostaglandin E2 and prostaglandin F2α. PPME protected brain through decreasing the aluminum accumulation and stimulating antioxidant activities and anti-apoptotic proteins namely Bcl-2. Therefore, these results indicated that pomegranate peel methanolic extract could inhibit aluminum-induced oxidative stress and histopathological alternations in brain of female rats, and these effects may be related to anti-apoptotic and antioxidants activities.

Borax counteracts genotoxicity of aluminum in rat liver

This study was carried out to evaluate the protective role of borax (BX) on genotoxicity induced by aluminum (Al) in rat liver, using liver micronucleus assay as an indicator of genotoxicity. Sprague-Dawley rats were randomly separated into six groups and each group had four animals. Aluminum chloride (AlCl3; 5 mg/kg b.w.) and BX (3.25 and 13 mg/kg b.w.) were injected intraperitoneally to rats. Besides, animals were also treated with Al for 4 consecutive days followed by BX for 10 days. Rats were anesthetized after Al and BX injections and the hepatocytes were isolated for counting the number of micronucleated hepatocytes (MNHEPs). AlCl3 was found to significantly ( p < 0.05) increase the number of MNHEPs. Rats treated with BX, however, showed no increase in MNHEPs. Moreover, simultaneous treatments with BX significantly modulated the genotoxic effects of AlCl3 in rats. It can be concluded that BX has beneficial influences and has the ability to antagonize Al toxicity.

The genotoxic, hepatotoxic, nephrotoxic, haematotoxic and histopathological effects in rats after aluminium chronic intoxication

Aluminium (Al) is used in water purification and is also present in several manufactured foods and medicines. Al is known to induce a broad range of physiological, biochemical and behavioural dysfunctions in laboratory animals and humans. This investigation was carried out to investigate the effects of subchronic exposure to Al (as AlCl3) in rats. Sprague-Dawley rats were randomly separated into two groups. Group 1 rats treated with sodium chloride served as the control, group 2 rats were treated with Al (as AlCl3, 5 mg/kg body weight) intraperitonally for 10 weeks. Animals were killed and blood samples were analyzed for blood serum alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) enzyme activities and creatinine, urea (U) and uric acid (UA) levels for evaluating hepatotoxicity and nephrotoxicity. Blood parameters including red blood cells (RBCs), haemoglobin (Hb) concentration, haematocrit (Ht), platelets (PLTs) and white blood cells (WBCs) were compared between control and experimental group to assess haematoxicity. In order to determine the genotoxicity, the number of micronucleated hepatocytes (MNHEPs) was counted in isolated hepatocytes. In addition, histological alterations in liver and kidney samples were investigated. After exposure with Al, the enzymatic activities of ALP, AST, ALT and LDH, and the levels of U and UA significantly increased. RBC, WBC, PLT, Hb and Ht revealed significant decreases in experimental group compared to the control. AlCl3 caused a significant increase in MNHEPs. Furthermore, severe pathological damages were established in both liver and kidney samples. Subchronic exposure to low doses of Al can produce serious dysfunctions in rat blood, liver and kidney, and exposure to this metal can result in greater damages.

Is boron a prebiotic element? A mini-review of the essentiality of boron for the appearance of life on earth

Boron is probably a prebiotic element with special importance in the so-called "sugars world". Boron is not present on Earth in its elemental form. It is found only in compounds, e.g., borax, boric acid, kernite, ulexite, colemanite and other borates. Volcanic spring waters sometimes contain boron-based acids (e.g., boric, metaboric, tetraboric and pyroboric acid). Borates influence the formation of ribofuranose from formaldehyde that feeds the "prebiotic metabolic cycle". The importance of boron in the living world is strongly related to its implications in the prebiotic origins of genetic material; consequently, we believe that throughout the evolution of life, the primary role of boron has been to provide thermal and chemical stability in hostile environments. The complexation of boric acid and borates with organic cis-diols remains the most probable chemical mechanism for the role of this element in the evolution of the living world. Because borates can stabilize ribose and form borate ester nucleotides, boron may have provided an essential contribution to the "pre-RNA world".