Protection of arsenic-induced testicular oxidative stress by arjunolic acid

Effect of quercetin and mirtazapine on spermatogenesis and testis structure in phenylhydrazine-induced hemolytic anemia mice: An experimental study

Anemia poses a significant healthcare challenge across different socioeconomic groups and can result in reproductive system damage through the generation of free radicals and lipid peroxidation. This study examines the protective effects of quercetin (QUE) and mirtazapine (MIR) against the reproductive damage caused by phenylhydrazine (PHZ) in mice. Fifty NMRI mice, aged 8-10 weeks with an average weight of 27.0 ± 2.0 g, were randomly divided into five groups. The control group (Group 1) received oral administration of 10 mL/kg/day of normal saline. Group 2 (PHZ group) received an initial intraperitoneal dose of 8 mg/100 g body weight of PHZ, followed by subsequent doses of 6 mg/100 g every 48 h. Group 3 received PHZ along with oral QUE at a dosage of 50 mg/kg/day. Group 4 received PHZ along with oral MIR at a dosage of 30 mg/kg/day. Group 5 received PHZ along with oral QUE at a dosage of 50 mg/kg/day and MIR at a dosage of 30 mg/kg/day. The treatment duration was 35 days. Sperm samples were collected from the caudal region of the epididymis post-euthanasia to assess the total mean sperm count, sperm viability, motility, DNA damage, and morphology. Testicular tissue was employed to quantify total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) concentrations, while serum levels of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were analyzed. Additionally, various aspects, including testicular histopathology, oxidative enzyme levels, gene expression related to apoptosis and antiapoptotic pathways, and in vivo fertility index, were evaluated after 35 days. The QUE, MIR, and QUE + MIR groups showed less abnormal morphology and DNA damage, as well as better total and progressive sperm motility, motility characteristics, viability, and plasma membrane function compared to the PHZ group. QUE, MIR, and QUE + MIR administration increased TAC, SOD, and GPx activities in testicular tissue, while reducing MDA levels compared to the PHZ group. Furthermore, QUE, MIR, and QUE + MIR significantly reduced Bax, and caspase-3 expression levels, and increased Bcl-2 expression levels, compared to the PHZ group. Mice treated with QUE, MIR, and QUE + MIR exhibited an increased in vivo fertility index and plasma sex hormone levels compared to the PHZ group. These results show that QUE, MIR, and QUE + MIR might be able to improve the fertility index, boost the testicular antioxidant defense system, and control the death of germ cells. This could mean that they could be used to treat mice with PHZ-induced testicular damage.

Mitigation of arsenic poisoning induced oxidative stress and genotoxicity by Ocimum gratissimum L

Arsenic toxicity is a major problem across the world due to geogenic activity and has been supposed to generate free radicals and genotoxicity among the arsenic-poisoned population. There is a need to find suitable free radical quenching compounds for the arsenic-induced free radical-affected population. In the present study, Na3AsO3- induced oxidative stress and genotoxicity were evaluated in Oryctolagus cuniculus L, and quenching competency of Ocimum species was examined by applying enzymatic and non-enzymatic in vitro tests, comet assay, and Random Amplified Polymorphic Deoxyribonucleic acid - Polymerase Chain Reaction (RAPD-PCR) methods. In the present study, oxidative damage due to Na3AsO3 intoxication in O. cuniculus L has been confirmed followed by substantive genotoxicity, and in a further study, it has also been reported that the extract of O. gratissimum L lowers the oxidative stress in experimental animals confirmed by a decrease in Malondialdehyde (MDA) 4.78 ± 0.05 (nmol/mg protein), and an increase in Glutathione (GSH) 2.87 ± 0.50 (μmoles/mg proteins), Superoxide Dismutase (SOD) 1.78 ± 0.03(Units/mg protein), Catalase (CAT) 2.72 ± 0.02 (μmoles of H2O2 consumed/min/mg proteins) and Glutathione peroxidase (GPX) 7.43 ± 0.01 (μg of glutathione utilized/min/mg protein). A positive impact of extract of O. gratissimum L on protection of genotoxicity has been also confirmed by Random Amplified Polymorphic DNA (RAPD) based reduction in polymorphic bands of Deoxyribonucleic acid (DNA) from 6.5 to 3.16 and comet assay-based increase in head DNA % (87.86 ± 1.58), tail moment (1.07 ± 0.27) and decrease in tail DNA % (12.13 ± 1.58) & tail length (8.2 ± 1.46) at 5% P in lymphocytes. A significant level reduction in free radicals and reduction in DNA polymorphism has proved the competency of test material for the development of suitable antidotes against arsenicosis.

The Impact of Acute Low-Dose Gamma Irradiation on Biomass Accumulation and Secondary Metabolites Production in Cotinus coggygria Scop. and Fragaria × ananassa Duch. Red Callus Cultures

Cotinus coggygria Scop. (smoketree) and Fragaria × ananassa Duch. (strawberry) are two industrially important species due to their composition in bioactive compounds. In this study, we investigated the effects of acute low-dose gamma irradiation (15, 20, 25, 30, 35 and 40 Gy) on two red callus cultures established in smoketree and strawberry. The biomass production, dry weight, content of phenols, flavonoids, monomeric anthocyanins', index of anthocyanins polymerization and antioxidant activity were evaluated. For the smoketree callus, a negative correlation between irradiation doses and callus biomass accumulation was observed. For the strawberry callus, irradiation did not significantly affect the accumulation of the biomass. An increased dry weight was observed in irradiated smoketree callus, while for treated strawberry callus, a decrease was recorded. Irradiation with 30 Gy was stimulative for polyphenols' accumulation in both cultures; however, the increase was significant only in the strawberry callus. The flavonoids increased in the 30 Gy strawberry variants, while it significantly decreased in smoketree callus irradiated with 35 and 40 Gy. In irradiated strawberry callus, except for the 25 Gy variant (1.65 ± 0.4 mg C-3-GE/g DW), all treatments caused an increase in anthocyanins' accumulation. In smoketree, except for the 15 Gy variant (2.14 ± 0.66 mg C-3-GE/g DW), the irradiation determined an increase in anthocyanins synthesis, with the highest value being seen in the 20 Gy variant (2.8 ± 0.94 mg C-3-GE/g DW). According to UPLC-HRMS investigations, an unidentified compound increased by 99% at the 30 Gy dose in strawberry callus, while in smoketree, maslinic acid increased by 51% after irradiation with 40 Gy. The results of this study showed, for the first time, the differential response of two performant callus cultures to low-dose gamma irradiation, a biotechnological method that can be used to stimulate the synthesis of important flavonoids and triterpenes.

The Protective Effects of Trametes Versicolor on Arsenic-Induced Male Reproductive Toxicity through Regulation of Oxidative Stress: A Biochemical and Histopathological Survey

Exposure to arsenic is linked to a wide range of diseases, in particular male reproductive toxicities. Trametes versicolor is a traditional medicinal fungus with a remarkable potential for antioxidant activity. The purpose of this study was to examine the ameliorating effects of water and methanol extracts of T. versicolor on arsenic-induced male reproductive toxicities via the abrogation of oxidative stress. The mice were divided as follows: control: normal saline, As: arsenic (15 mg/kg), WE: water extract (400 mg/kg), ME: methanol extract (400 mg/kg), As + WE: arsenic (15 mg/kg) + water extract (100, 200, 400 mg/kg), As + ME: arsenic (15 mg/kg) + methanol extract (100, 200, 400 mg/kg), and positive control: arsenic (15 mg/kg) + vitamin C (500 mg/kg). Animals were treated via the intraperitoneal route. About 24 hr later, the mice were euthanized, and oxidative stress parameters (reactive oxygen species [ROS], lipid peroxidation, glutathione concentration, protein carbonylation, glutathione peroxidase, and superoxide dismutase activity), histopathological changes and sperm parameters (count, motility, and morphology) were examined in the testicular tissue. Arsenic caused significant pathological changes in the testicular tissue and sperm morphology and significantly reduced sperm count and motility. Moreover, arsenic mediated oxidative stress via significant increases in ROS generation, lipid peroxidation, and protein carbonyl content, as well as significant depletion in glutathione concentration and superoxide dismutase and glutathione peroxidase activities. Although, coadministration of water and methanol extracts of T. versicolor at 200 and 400 mg/kg counteracted arsenic-induced oxidative and histopathological damages and improved sperm parameters. Our study indicated that T. versicolor ameliorated arsenic-induced testis toxicity and sperm dysfunction via attenuation of oxidative damage.

Gold nanoparticle intratesticular injections as a potential animal sterilization tool: Long-term reproductive and toxicological implications

This study aimed to evaluate the gold nanoparticles (AuNPs) animal sterilizing potential after intratesticular injections and long-term adverse reproductive and systemic effects. Adult male Wistar rats were divided into control and gold nanoparticle (AuNPs) groups. The rats received 200µL of saline or AuNPs solution (16µg/mL) on experimental days 1 and 7 (ED1 and ED7). After 150 days, the testicular blood flow was measured, and the rats were mated with females. After mating, male animals were euthanized for histological, cellular, and molecular evaluations. The female fertility indices and fetal development were also recorded. The results indicated increased blood flow in the testes of treated animals. Testes from treated rats had histological abnormalities, shorter seminiferous epithelia, and oxidative stress. Although the sperm concentration was lower in the AuNP-treated rats, there were no alterations in sperm morphology. Animals exposed to AuNPs had decreased male fertility indices, and their offspring had lighter and less efficient placentas. Additionally, the anogenital distance was longer in female fetuses. There were no changes in the histology of the kidney and liver, the lipid profile, and the serum levels of LH, testosterone, AST, ALT, ALP, albumin, and creatinine. The primary systemic effect was an increase in MDA levels in the liver and kidney, with only the liver experiencing an increase in CAT activity. In conclusion, AuNPs have a long-term impact on reproduction with very slight alterations in animal health. The development of reproductive biotechnologies that eliminate germ cells or treat local cancers can benefit from using AuNPs.

Changes in heavy metal levels, reproductive characteristics, oxidative stress markers and testicular apoptosis in rams raised around thermal power plant

Male reproductive dysfunction is one of the damages in the organism caused by heavy metals. In this study, it was aimed to investigate the changes in heavy metal levels in serum and testicular tissue, and serum hormone levels, epididymal spermatozoa characteristics, tissue oxidative stress levels, testicular histology and testicular apoptosis level in rams raised in remote and near regions of a thermal power plant. A total of 75 rams were divided into 3 groups according to the regions, where they were born and raised, being far [250 km distance, group 1 (control), n = 25], close (20 km distance, group 2, n = 25) and very close (10 km distance, group 3, n = 25) to the thermal power plant. The blood along with testis and epididymis tissues was taken from the animals after slaughtering. In addition, soil and water heavy metal analyzes were also performed. The highest levels of serum Al, Cr, As, Ag, Sn and testicular Al, V, Ni, Ag, Cd, Cr, As, Pb, and the lowest levels of serum Cu, testicular Cu and Zn were determined in group 3 compared to control. Soil and water heavy metal results were similar to those found in serum and testis. The lowest serum testosterone level, tissue glutathione-peroxidase and catalase activities, spermatozoon concentration, and the highest tissue malondialdehyde level, dead spermatozoon rate, Bax apoptotic protein expression level and Bax/Bcl-2 rate alongside some testicular histopathological lesions were found in group 3 in comparison to control. Significant correlations were determined between some heavy metal levels and some parameters measured. As a result, heavy metals accumulate in the soil and water in the region close to the thermal power plant. The endocrine and exocrine reproductive potentials of rams born and grown in these regions were clearly damaged by the increased testicular heavy metals due to water drank and herbs consumed.

Spirulina ameliorates arsenic induced reproductive toxicity in male rats

Spirulina (Spirulina platensis), has numerous health benefits including antioxidant, immunomodulatory, and anti-inflammatory activities, works against heavy metal toxicity, and is often used as a food supplement in human, animals, birds and fishes. This study aimed to evaluate the protective ability of the dietary spirulina against the toxic effects of inorganic arsenic (iAs) on male reproductive parameters in rats. Seventy-two mature Long-Evans male rats, dividing into six groups (T0, T1, T2, T3, T4 and T5) (12 rats/group) were included in this study. The T3, T4 and T5 group rats were treated with three consecutive doses (1.0 g, 1.5 g and 2.0 g/kg feed) of spirulina in feed along with 3.0 mg NaAsO₂/kg body weight (BW) in drinking water (DW) daily for 90 days. Each rat of group T1 received NaAsO₂ (3.0 mg/kg BW) in DW, and those of T2 group were fed with spirulina (2.0 g/kg feed) daily for 90 days. The rats of group T0 served as the control with normal feed and water. Total arsenic (tAs) contents, reproductive parameters (testicular weight, sperm motility and morphology), and histological changes in the testicles were evaluated in these rats. Arsenic dosing significantly (p=0.003, Kruskal-Wallis test) increased the tAs contents in the testicles, decreased testes weight, sperm morphology and motility compared to the controls. The effect of arsenic dosing was also evidenced by the histological changes like decreased germinal layers in the seminiferous tubules of the treated rats. Moreover, dietary spirulina (2.0 g/kg feed) supplementation significantly (p=0.011, Kruskal-Wallis test) lowered tAs contents in testicles and increases testes weights, sperm motility and morphology. Therefore, spirulina can be used as an effective dietary supplement to ameliorate the adverse effects of arsenic induced reproductive toxicities. However, further study is required to elucidate the underlying molecular mechanisms of reduction of arsenic induced reproductive toxicity by spirulina.

Environmental arsenic exposure and its contribution to human diseases, toxicity mechanism and management

Arsenic is a well-recognized environmental contaminant that occurs naturally through geogenic processes in the aquifer. More than 200 million people around the world are potentially exposed to the elevated level of arsenic mostly from Asia and Latin America. Many adverse health effects including skin diseases (i.e., arsenicosis, hyperkeratosis, pigmentation changes), carcinogenesis, and neurological diseases have been reported due to arsenic exposure. In addition, arsenic has recently been shown to contribute to the onset of non-communicable diseases, such as diabetes mellitus and cardiovascular diseases. The mechanisms involved in arsenic-induced diabetes are pancreatic β-cell dysfunction and death, impaired insulin secretion, insulin resistance and reduced cellular glucose transport. Whereas, the most proposed mechanisms of arsenic-induced hypertension are oxidative stress, disruption of nitric oxide signaling, altered vascular response to neurotransmitters and impaired vascular muscle calcium (Ca²⁺) signaling, damage of renal, and interference with the renin-angiotensin system (RAS). However, the contributions of arsenic exposure to non-communicable diseases are complex and multifaceted, and little information is available about the molecular mechanisms involved in arsenic-induced non-communicable diseases and also no suitable therapeutic target identified yet. Therefore, in the future, more basic research is necessary to identify the appropriate therapeutic target for the treatment and management of arsenic-induced non-communicable diseases. Several reports demonstrated that a daily balanced diet with proper nutrient supplements (vitamins, micronutrients, natural antioxidants) has shown effective to reduce the damages caused by arsenic exposure. Arsenic detoxication through natural compounds or nutraceuticals is considered a cost-effective treatment/management and researchers should focus on these alternative options. This review paper explores the scenarios of arsenic contamination in groundwater with an emphasis on public health concerns. It also demonstrated arsenic sources, biogeochemistry, toxicity mechanisms with therapeutic targets, arsenic exposure-related human diseases, and onsets of cardiovascular diseases as well as feasible management options for arsenic toxicity.

Arsenic co-carcinogenesis: Inhibition of DNA repair and interaction with zinc finger proteins

Arsenic is widely present in the environment and is associated with various population health risks including cancers. Arsenic exposure at environmentally relevant levels enhances the mutagenic effect of other carcinogens such as ultraviolet radiation. Investigation on the molecular mechanisms could inform the prevention and intervention strategies of arsenic carcinogenesis and co-carcinogenesis. Arsenic inhibition of DNA repair has been demonstrated to be an important mechanism, and certain DNA repair proteins have been identified to be extremely sensitive to arsenic exposure. This review will summarize the recent advances in understanding the mechanisms of arsenic carcinogenesis and co-carcinogenesis, including DNA damage induction and ROS generation, particularly how arsenic inhibits DNA repair through an integrated molecular mechanism which includes its interactions with sensitive zinc finger DNA repair proteins.

Ameliorative Effects of Caffeic Acid Against Arsenic-Induced Testicular Injury in Mice

Arsenic (As) is an environmental pollutant with destructive effects on different body organs, including the testis. This work was aimed to assess the ameliorative role of caffeic acid (CA) against As-provoked testicular damage in mice. Twenty-four adult male mice (31 ± 9 g) were randomly allocated to four equal groups. The first group served as control and was provided basal diet and tap water. Animals in the second group received water containing 200 ppm arsenite. The third group of mice received CA (60 mg/kg body weight; i.p.) during exposure to arsenite. Animals in the fourth group received CA. At the end of the experiment period (21 days), blood and testicular tissue sampling was done for biochemical and histopathological assessments. The results showed a significant decline of testicular ferric reducing antioxidant power (FRAP), superoxide dismutase, and glutathione peroxidase (GPx), as well as plasma concentrations of testosterone and dihydrotestosterone in As-treated mice compared to controls (p < 0.05). A significant increase in testicular malondialdehyde was also detected in group 2 relative to controls. Moreover, As exposure resulted in some morphological and histopathological alterations of the testis, including hyperemia, reduced tubular diameter and thickness of epithelial cell layers of seminiferous tubules, and Leydig cell necrosis. Simultaneous administration of CA plus As increased GPx, FRAP, testosterone, and dihydrotestosterone amounts and attenuated MDA levels as well as histopathological alterations to the levels that were not significantly different from those of the control group. These results indicate that caffeic acid can be suggested as an alleviative natural compound against As-induced damage in mice testes.

Tranilast abrogates cisplatin-induced testicular and epididymal injuries: An insight into its modulatory impact on apoptosis/proliferation

Cisplatin is a chemotherapeutic agent whose therapeutic use is greatly limited by the associated organs' toxicity and particularly, testicular toxicity. Cisplatin-induced testicular damage reported being mediated through mitochondria-mediated apoptosis, inflammation, and oxidative stress. Evidence showed that tranilast (TRN) has the ability to restore the oxidative status and modulate TRAIL/caspase-8 signaling. This led us to hypothesize that TRN could abrogate cisplatin-induced testicular and epididymal injuries via inhibiting oxidative stress and modulating proliferation and TRAIL/caspase-8/cJNK signaling. Cisplatin injection induced oligospermia and abnormalities in testicular and epididymal structure along with impaired oxidative status. TRN administration (100 or 300 mg/kg) for 7 days post-cisplatin injection preserved spermatogenesis and restored testicular and epididymal architecture, but restoration was more so in TRN300 than TRN100. This was in line with the restoration of balanced oxidative status as indicated by the increased total antioxidant capacity, glutathione and superoxide dismutase activity, and the decreased malondialdehyde content in testes (p < 0.05 vs. cisplatin). TRN increased the cell proliferation revealed by the increased expression of proliferating cell nuclear antigen in a dose-dependent manner (p < 0.05 vs. cisplatin) whereas only TRN300 decreased testicular cJNK, TRAIL, and caspase-8 expression (p < 0.05 vs. cisplatin). Moreover, TRN dose-dependently inhibited the pro-inflammatory transcription factor NF-kB and the cytokine TNF-α expressions in testes. In conclusion, TRN300 was more effective than TRN100 in alleviating cisplatin-induced testicular and epididymal injuries and in enhancing spermatogenesis. This curative effect of TRN might be mediated through its antioxidant and anti-inflammatory impacts along with its modulatory impact on cJNK/TRAIL/caspase-8 signaling favoring proliferation rather than apoptosis.

Transgenerational effects in DNA methylation, genotoxicity and reproductive phenotype by chronic arsenic exposure

An emerging concern is the influences of early life exposure to environmental toxicants on offspring characteristics in later life. Since recent evidence suggests a transgenerational transference of aberrant phenotypes from exposed-parents to non-exposed offspring related to adult-onset diseases including reproductive phenotype. The transgenerational potential of arsenic a well know genotoxic and epigenetic modifier agent has not been assessed in mammals until now. In this experimental study, we evaluated the transgenerational effects of arsenic in a rat model with chronic exposure to arsenic. Rats chronically exposed to arsenic in drinking water (1 mg As₂O₃/mL) (F0) were mated to produce the arsenic lineage (F1, F2, and F3). The arsenic toxic effects on were evaluated over the four generations by analyzing the DNA methylation percentage, genotoxicity in WBC and physical and reproductive parameters, including sperm quality parameters and histopathological evaluation of the gonads. Chronic exposure to arsenic caused genotoxic damage (F0-F3) different methylation patterns, alterations in physical and reproductive parameters, aberrant morphology in the ovaries (F0 and F1) and testicles (F1-F3), and a decrease in the quality of sperm (F0-F3, except F2). Parental chronic arsenic exposure causes transgenerational genotoxicity and changes in global DNA methylation which might be associated with reproductive defects in rats. Combined with recent studies reveal that disturbances in the early life of an individual can affect the health of later generations.

Zingiber officinale ethanolic extract attenuates oxidative stress, steroidogenic gene expression alterations, and testicular histopathology induced by sodium arsenite in male rats

Arsenic (As) indelibly exists in the environment and may reach to a food chain. Flavors and herbs are recognized sources of natural antioxidants that play imperative against harmful chemical pollutants. Ginger is utilized around the world as a zesty condiment. This study assessed the ability of ginger extract (GE) as a protector to improve regenerative disabilities initiated by sodium arsenate in reproductive functions in male rats. Thirty-two Sprague-Dawley male rats weighted 240 ± 10 g were arbitrarily relegated into four experimental groups (n = 8): the control group; the GE-treated group received at 100 mg/kg BW; the As-treated group received sodium arsenite at 10 mg/kg BW; the fourth group received sodium arsenite additionally GE at mentioned doses for 4 weeks. Phytochemical results of GE revealed that GE had good antioxidative characteristics and high content of total flavonoid, tannins, alkaloids, and total phenolic components. Simultaneously, treatment of GE showed protection against oxidative stress induced by As and restoration of the serum cholesterol, testosterone, LH, and sperm parameter to normal levels. GE significantly improved the antioxidant activities (GSH, SOD, and CAT) as well as H2O2 and MDA in rats received concurrently the GE and As compared with control group. Moreover, the expression of genes controlling the cholesterol transportation and testosterone synthesis (SR-B1, StAR, CYP11A1, 3b-HSD, 17b-HSD, and CYP17a) as well as LHR showed a meaningful improvement in rats treated by GE plus As compared with their expression in the As-treated group. Besides, GE treatment exhibited significant recovered testis histopathological alterations, reduced the arsenic content in testes, and improved the sperm parameters.

Casein- and pea-enriched high-protein diet can take care of the reprotoxic effects of arsenic in male rats

Arsenic toxicity is a significant health problem featured with several incidents of male reproductive dysfunctions. We studied the protective effects of a casein- and pea-enriched formulated high-protein diet (FHPD) on arsenic-mediated testicular dysfunctions in rats. Adult male rats sustained on either a benchmark diet (n = 8) or an isocaloric FHPD (n = 8) were gavaged with arsenic trioxide (3mg/kg body wt/rat/day) for 30 consecutive days. A vehicle-fed group (n = 8) maintained on the standard diet served as control. The arsenic-treated group continued on the standard diet had a significantly reduced testicular and accessory sex organs weights. They exhibited decreased count, motility, viability and disrupted plasma membrane integrity of caudal spermatozoa with a higher incidence of gross morphological anomalies and DNA damage. Attenuated steroidogenic enzyme activities and low serum testosterone level vouched for a compromised state of testicular steroidogenesis. An increased testicular malondialdehyde and protein carbonyl contents coupled with impaired activities of antioxidant enzymes and free radical scavengers mirrored a situation of exacerbated testicular oxidative imbalance and disrupted redox homeostasis. FHPD, by and large, countermanded testicular steroidogenesis and antioxidant defence system and revoked the ill effects of arsenic. We conclude that specific protein-enriched diet may serve as prospective weaponry in encountering the arsenic-threatened testicular functions.

Arsenite induces testicular oxidative stress in vivo and in vitro leading to ferroptosis

Ferroptosis is a newly identified form of cell death characterized by accumulation of intracellular iron and requirement of lipid peroxidation. However, whether arsenite triggers testicular cell death via ferroptosis remains unclear. In this study, after administrating of adult male mice with 0.5, 5 and 50 mg/L arsenite for six months via drinking water, the results showed that arsenite caused the pathological changes in mouse testis and significantly reduced the number of sperm. Mitochondrial injuries were observed as the major ultrastructural damages induced by arsenite, and these damages were accompanied by the apparent mitochondrial oxidative damage in the testis, manifested by accumulation of iron, production of reactive oxygen species and lipid peroxidation products. We also demonstrated that arsenite significantly activated ferroptosis-related signal pathways in the mouse testis. To further verify the results obtained in the animal model, GC-2spd cells were employed as the in vitro culture system. Consistently, the results revealed arsenite remarkably triggered the ferroptotic cell death in vitro, and inhibition of ferroptosis by ferrostatin-1 could attenuate this adverse effect in cells. These findings together indicate that arsenite can trigger oxidative stress thus leading to testicular cell death by ferroptosis, suggesting that inhibition of ferroptosis would be a potential strategy for treatment of arsenite-related male reproductive toxicity.

Sodium Arsenite Injection Induces Ovarian Oxidative Stress and Affects Steroidogenesis in Rats

Oxidative stress is involved in the regulation of mammalian reproduction. The present study was conducted to detect the sodium arsenite-induced oxidative stress and alterations in the structure and steroidogenesis in rat ovary. Twenty female adult rats were injected i.p. with sodium arsenite (8 mg/kg BW, T) or 0.9% saline (C) for 16 days. The oxidative stress indexes and morphology of the liver, kidney, and ovary were detected using commercial kits and HE staining, respectively. The serum progesterone and estradiol were detected by RIA, and the ovarian steroidogenic gene expressions were detected by real-time PCR. Results showed that the ovarian activities of SOD and GSH-PX decreased (P < 0.05), while the ROS activity and MDA level increased (P < 0.05) in the T group. HE staining results showed that treatment with sodium arsenite damaged the ovarian morphology, resulting in reduced large and medium follicles and increased atretic follicles. Nonetheless, neither the liver nor kidney showed evident changes in the oxidative stress indexes or morphology after sodium arsenite treatment. The serum progesterone and estradiol levels decreased (P < 0.05) with the reduced expressions in the ovarian steroidogenic genes (StAR, P450scc, and 3β-HSD) (P < 0.05). In conclusion, sodium arsenite injection can induce ovarian oxidative stress in rats which set up an appropriate model for future studies of ovarian diseases as well as the toxic mechanism of arsenic in the reproduction.

An overview of plant-based interventions to ameliorate arsenic toxicity

The industrial and technological advancements in the world have also contributed to the rapid deterioration in the environment quality through introduction of obnoxious pollutants that threaten to destroy the subtle balance in the ecosystem. The environment contaminants cause severe adverse effects to humans, flora and fauna that are mostly irreversible. Chief among these toxicants is arsenic, a metalloid, which is considered among the most dangerous environmental toxins that leads to various diseases which affect the quality of life even when present in small quantities. Treatment of arsenic-mediated disorders still remains a challenge due to lack of effective options. Chelation therapy has been the most widely used method to detoxify arsenic. But this method is associated with deleterious effects leading various toxicities such as hepatotoxicity, neurotoxicity and other adverse effects. It has been discovered that indigenous drugs of plant origin display effective and progressive relief from arsenic-mediated toxicity without any side-effects. Further, these phytochemicals have also been found to aid the elimination of arsenic from the biological system and therefore can be more effective than conventional therapeutic agents in ameliorating arsenic-mediated toxicity. This review presents an overview of the toxic effects of arsenic and the therapeutic strategies that are available to mitigate the toxic effects with emphasis on chelation as well as protective and detoxifying activities of different phytochemicals and herbal drugs against arsenic. This information may serve as a primer in identifying novel prophylactic as well as therapeutic formulations against arsenic-induced toxicity.

Arsenic aggravated reproductive toxicity in male rats exposed to lead during the perinatal period

The aim of this study was to assess the reproductive toxic effects of arsenic on adult Wistar rats exposed to lead during the perinatal period. The pregnant rats were allowed ad libitum access to tap water containing 819 mg of lead (Pb) per L or without Pb from conception until weaning. Litter size, survival rate and developmental milestones of the pups delivered by Pb exposed dams were comparable to those of the control rats. Conversely, the pups exposed to Pb during the perinatal period exhibited significant delay in cliff avoidance, negative geotaxis, surface righting reflex, ascending wire mesh and testis descent. The control and perinatal Pb-exposed male rats were maintained on tap water containing 2.3 mg of arsenite (As) per L or without arsenite from the pubertal period (post-natal day 55) to adulthood (post-natal day 115) and assessed for reproductive end points. The results revealed that the (1) relative weights of the testis, epididymis, seminiferous tubules and ventral prostate; (2) daily sperm production; (3) epididymal sperm density and (4) numbers of motile, viable, and HOS tail swelled sperm declined significantly in the rats exposed to either Pb or As. The activity levels of testicular 3β- and 17β-hydroxysteroid dehydrogenases were also significantly decreased in the experimental rats. Significant elevation in the levels of reactive oxygen species and lipid peroxidation in association with reduced activities of antioxidant enzymes in the testis and different epididymal regions was recorded in the experimental rats. In the fertility study, although each male in the control and experimental groups produced a copulatory plug and impregnated a female, the mean conception time significantly increased in the experimental groups. The mean number of implantations decreased significantly in the females mated with the experimental males. Moreover, the results of the present study also indicate that reproductive alterations were more deteriorated in the Pb-exposed rats treated with arsenic when compared to individual exposures. In conclusion, the data clearly suggest that reproductive toxicity in male rats exposed to Pb during the perinatal period is exacerbated by As treatment during the pubertal period.

Effect of betaine versus arsenite-induced alterations of testicular oxidative stress and circulating androgenic indices in rats

The aim of this work was to study the alleviative role of betaine versus arsenite-provoked alterations in testis oxidative status and circulating androgenic indices. Twenty-four adult male rats (204.5 ± 21 g) were divided into four groups, equally. Control group was given basal diet and tap water. Group 2 rats received arsenite (100 mg/L) in drinking water. Rats in group 3 received betaine (2% of the diet) during arsenite exposure. Group 4 received betaine at 2% of the diet during study period (30 days). The results revealed significant decrease in testicular glutathione peroxidase, catalase and glutathione in arsenite-treated animals relative to controls. Significant increase in testicular malondialdehyde was also detected in arsenite-exposed group. Concurrent administration of betaine with arsenite significantly increased glutathione and catalase amounts in comparison with arsenite group. Arsenite exposure resulted in a significant decrease in plasma testosterone and dihydrotestosterone levels over control rats, whereas supplementation of betaine augmented the hormones concentrations to the levels that had no significant difference in comparison with controls. Concentration of all measured oxidative status and hormonal variables in the betaine plus arsenite and betaine groups was not significantly different relative to controls. Taken together, betaine may be proposed as an alleviative agent against arsenite-induced male reprotoxicity.

Ellagic acid: A promising protective remedy against testicular toxicity induced by arsenic

Chronic exposure to arsenic, an inducer of oxidative stress, is one of the major causes of male infertility. Therefore, the present study investigated the protective role of Ellagic acid (EA), as a natural antioxidant, against testicular toxicity evoked by arsenic. Thirty-five male Wistar rats were divided into 5 treatment groups. Group 1 served as control, group 2 were orally exposed to sodium arsenite (SA, 10 mg/kg; 21 days), groups 3 and 4 were initially exposed to SA for 7 days and then were treated with both EA (10 and 30 mg/kg) and SA up to 21 days, and group 5 was treated with EA for 14 days. After this period, biochemical and histopathological parameters were evaluated in serum samples and testicular tissue. SA markedly reduced levels of serum testosterone, total antioxidant capacity, reduced glutathione as well as the activity of antioxidant enzymes. Furthermore, SA enhanced levels of malondialdehyde, tumor necrosis factor-α, interleukin-1β and nitric oxide in testes. Treatment with EA was found to reduce testicular arsenic accumulation and oxidative stress parameters. In addition, EA improved the serum testosterone level, testicular antioxidant markers and histological parameters after exposure to SA. EA may emerge as a promising therapeutic option to protect testes from arsenic-induced toxicity through reducing oxidative stress and inflammatory responses.

Fertility in male rats: Disentangling adverse effects of arsenic compounds

Arsenic impairs male reproductive functions. However, it is not clear whether different arsenic compounds similarly affect fertility. In this study, we compared the impact of sodium arsenite and arsenate on sperm quality and fertility. After 56 d exposure, male Wistar rats were mated and pregnant females were evaluated by fertility indexes. Clearly, exposure to 10 mg/L arsenite reduced daily sperm production via H₂O₂ overproduction and germ cells loss. Animals from this group also showed a decrease in epididymal sperm counts and percentage of sperm with intact membranes. Moreover, they presented low fertility potential and high preimplantation loss. In contrast, 10 mg/L arsenate caused oxidative stress in testis, mineral imbalance in epididymis, and sperm membranes damage, with no effects on fertility. Both arsenic compounds at 0.01 mg/L altered reproductive parameters. We concluded that arsenite is more harmful than arsenate to sperm quality and male fertility, with negative influences in early pregnancy.

Arjunolic Acid Improves the Serum Level of Vitamin B12 and Folate in the Process of the Attenuation of Arsenic Induced Uterine Oxidative Stress

Continuation of prolonged treatment against arsenicosis with conventional chelating therapy is a global challenge. The present study was intended to evaluate the defensive effect of arjunolic acid against arsenic-induced oxidative stress and female reproductive dysfunction. Wistar strain adult female rats were given sodium arsenite (10 mg/kg body weight) in combination with arjunolic acid (10 mg/kg body weight) orally for two estrous cycles. Electrozymographic analysis explored that arjunolic acid co-treatment counteracted As³⁺-induced ROS production in uterine tissue by stimulating the activities of endogenous enzymatic antioxidants. Arjunolic acid was able to enhance the protection against mutagenic uterine DNA breakage, necrosis, and ovarian-uterine tissue damages in arsenicated rats by improving the ovarian steroidogenesis. The mechanisms might be coupled with the augmentation of antioxidant defense system, partly through the elimination of arsenic with the involvement of S-adenosyl methionine pool where circulating levels of vitamin B₁₂, folic acid, and homocysteine play critical roles as evidenced from our present investigation.

Medicinal plants and natural products in amelioration of arsenic toxicity: a short review

CONTEXT

Chronic arsenic toxicity (arsenicosis) is considered a serious public health menace worldwide, as there is no specific, safe, and efficacious therapeutic management of arsenicosis.

OBJECTIVES

To collate the studies on medicinal plants and natural products with arsenic toxicity ameliorative effect, active pre-clinically and/or clinically.

METHODS

Literature survey was carried out by using Google, Scholar Google and Pub-Med. Only the scientific journal articles found on the internet for last two decades were considered. Minerals and semi-synthetic or synthetic analogs of natural products were excluded.

RESULTS

Literature study revealed that 34 medicinal plants and 14 natural products exhibited significant protection from arsenic toxicity, mostly in preclinical trials and a few in clinical studies.

CONCLUSION

This research could lead to development of a potentially useful agent in clinical management of arsenicosis in humans.

Antioxidant and glucose metabolizing potential of edible insect, Brachytrupes orientalis via modulating Nrf2/AMPK/GLUT4 signaling pathway

Brachytrupes orientalis (Gryllidae) is a common edible insect species eaten by the different tribes of North East India. This study investigated the potentiality of Brachytrupes orientalis extracts in different solvent hydro-alcoholic (AEBO), hexane (HEBO) and ethyl acetate (EEBO) on glucose utilization and cell viability in high glucose (HG) treated myotubes. It has been observed that AEBO supplementation significantly increased the glucose utilization against HG exposure; however, treatment HEBO and EEBO have no significant effect. AEBO also increased the intercellular glucose-6-phosphate level and the protein expression of both phospho-AMPK and GLUT4 in HG treated myotubes in a dose dependent manner. Furthermore, supplementation with AEBO decreased the intercellular ROS production, lipid peroxidation, and up-regulated the protein expression of Nrf2 and GST. Chromatography and Spectroscopic analyses of AEBO also suggest that Ursolic acid may be one of the bioactive principles with rich potassium, sodium, calcium and magnesium content.

Silymarin Protects Mouse Liver and Kidney from Thioacetamide Induced Toxicity by Scavenging Reactive Oxygen Species and Activating PI3K-Akt Pathway

Silymarin (SMN) has been shown to possess a wide range of biological and pharmacological effects. Besides, SMN has antioxidant and free radical scavenging activities. Thioacetamide (TAA) is a well-documented liver toxin that requires oxidative bioactivation to elicit its hepatotoxic effect which ultimately modifies amine-lipids and proteins. Our study has been designed in a TAA exposed mouse model to investigate whether SMN could protect TAA-induced oxidative stress mediated hepatic and renal damage. Results suggest that TAA generated reactive oxygen species (ROS), caused oxidative stress and induced apoptosis in the liver and kidney cells via JNK as well as PKC and MAPKs signaling. All these detrimental effects of TAA could, however, be suppressed by SMN which not only scavenged ROS but also induced PI3K-Akt cell survival pathway in the liver and prevented apoptotic pathways in both the organs. Histological studies, collagen staining and DNA fragmentation analysis also supported our results. Combining, we say that SMN possess beneficial role against TAA mediated hepatic and renal pathophysiology.

Curcumin Inhibits The Adverse Effects of Sodium Arsenite in Mouse Epididymal Sperm

Background

The aim of this study was to investigate the effects of curcumin on epididy- mal sperm parameters in adult male Navel Medical Research Institute (NMRI) mice ex- posed to sodium arsenite.

Materials and Methods

In this experimental study, we divided the animals into four groups: control, sodium arsenite (5 mg/kg), curcumin (100 mg/kg) and curcumin+sodium arsenite. Exposures were performed by intraperitoneal injections for a 5-week period. After the exposure period, we recorded the animals’ body and left testes weights. The left caudal epididymis was used to count the sperm number and analyze motility, viability, morphological abnormalities, acrosome reaction, DNA integrity, and histone-protamine replacement in the spermatozoa. One-way analysis of variance (ANOVA) followed by the Tukey’s test was used to assess the statistical significance of the data with SPSS 16.0. P<0.05 was considered significant.

Results

Mice exposed to sodium arsenite showed a significant decrease in the num- ber, motility, viability, normal sperm morphology and acrosome integrity of spermato- zoa compared to the control group. In the curcumin+sodium arsenite group, curcumin significantly reversed these adverse effects to the point where they approximated the control. In addition, the application of curcumin alone had no significant difference in these parameters compared to the control and curcumin+sodium arsenite groups. However, we observed no significant differences in the body and the testis weight as well as the DNA integrity and histone-protamine replacement in the spermatozoa of the four groups.

Conclusion

Curcumin compensated for the toxic effects of sodium arsenite on a number of sperm parameters in adult mice.

Effects of Sodium Arsenite and Arsenate in Testicular Histomorphometry and Antioxidants Enzymes Activities in Rats

The main source of environmental arsenic exposure in most countries of the world is drinking water in which inorganic forms of arsenic predominate. The present study was aimed to test the impact of two different compounds of inorganic arsenic in histomorphometric and enzymatic parameters in the testes by oral exposition. Adult Wistar male rats were exposed to sodium arsenite and arsenate in drinking water, testing for each chemical form the concentrations of 0.01 and 10 mg/L per 56 days. The animals intoxicated with arsenic, mainly sodium arsenite, showed reduction in the percentage of seminiferous epithelium and in proportion and volume of Leydig cells. Moreover, there was an increase in the percentage of tunica propria, lumen, lymphatic space, blood vessels, and macrophages. The activity of superoxide dismutase (SOD) did not change among the groups. However, the activity of catalase (CAT) decreased in animals exposed to both arsenic compounds. In addition, the higher concentration of arsenic, mainly as sodium arsenite, caused vacuolization in the seminiferous epithelium. The body and testes weight as well as testosterone concentration remained unchanged among the groups. In conclusion, exposition to arsenic, mainly as sodium arsenite, caused alteration in histomorphometric parameters and antioxidant defense system in the testes.

Protective effect of taurine against potassium bromate-induced hemoglobin oxidation, oxidative stress, and impairment of antioxidant defense system in blood

Potassium bromate (KBrO3 ) is widely used as a food-additive and is a major water disinfection by-product. KBrO3 causes severe toxicity in humans and experimental animals. Bromate is considered a probable human carcinogen and a complete carcinogen in animals. We have investigated the potential role of taurine in protecting against KBrO3 -induced oxidative stress in rat blood. Animals were given taurine for 5 days prior to KBrO3 and then sacrificed. Blood was collected and used to prepare hemolysates and plasma, which were then used for the analysis of several biochemical parameters. Administration of single oral dose of KBrO3 alone induced hepato- and nephro-toxicity as evident by elevated marker levels in plasma. Lipid peroxidation and protein oxidation were increased both in plasma and erythrocytes, suggesting the induction of oxidative stress. KBrO3 increased methemoglobin, nitric oxide, and hydrogen peroxide levels. It also altered the activities of the major antioxidant enzymes and lowered the antioxidant power of blood. Administration of taurine, prior to treatment with KBrO3 , resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. These results show that taurine is effective in mitigating the oxidative insult induced in rat blood by KBrO3 .

The beneficial role of curcumin on inflammation, diabetes and neurodegenerative disease: A recent update

The concept of using phytochemicals has ushered in a new revolution in pharmaceuticals. Naturally occurring polyphenols (like curcumin, morin, resveratrol, etc.) have gained importance because of their minimal side effects, low cost and abundance. Curcumin (diferuloylmethane) is a component of turmeric isolated from the rhizome of Curcuma longa. Research for more than two decades has revealed the pleiotropic nature of the biological effects of this molecule. More than 7000 published articles have shed light on the various aspects of curcumin including its antioxidant, hypoglycemic, anti-inflammatory and anti-cancer activities. Apart from these well-known activities, this natural polyphenolic compound also exerts its beneficial effects by modulating different signalling molecules including transcription factors, chemokines, cytokines, tumour suppressor genes, adhesion molecules, microRNAs, etc. Oxidative stress and inflammation play a pivotal role in various diseases like diabetes, cancer, arthritis, Alzheimer's disease and cardiovascular diseases. Curcumin, therefore, could be a therapeutic option for the treatment of these diseases, provided limitations in its oral bioavailability can be overcome. The current review provides an updated overview of the metabolism and mechanism of action of curcumin in various organ pathophysiologies. The review also discusses the potential for multifunctional therapeutic application of curcumin and its recent progress in clinical biology.

Protective effect of arjunolic acid against atorvastatin induced hepatic and renal pathophysiology via MAPK, mitochondria and ER dependent pathways

3-Hydroxy-3-methylglutaryl-CoA reductase inhibitor, atorvastatin (ATO), is a highly effective drug used for the treatment of hypercholesterolemia and hypertriglyceridemia. Its application is restricted now-a-days due to several acute and chronic side effects. ATO induced anti hypercholesterolemia and hepatic tissue toxicity has been reported to follow different mechanisms. The present study has been carried out to investigate the protective role of arjunolic acid (AA) against ATO induced oxidative impairment and cell death in hepatic and renal tissue in mice. Administration of ATO (at a dose 30 mg/kg/day for 8 weeks) enhanced serum markers, increased reactive oxygen species (ROS) production and altered the pro oxidant-antioxidant status of liver and kidney tissues. Our experimental evidence suggests that ATO exposure induces apoptotic cell deathby the activation of caspase-3 and reciprocal regulation of Bcl-2/Bax with the concomitant reduction of mitochondrial membrane potential and increased level of cytosolic cytochrome c, Apaf1, caspase-9. Besides, ATO markedly increased the phosphorylation of MAPKs, enhanced caspase-12 and calpain level. Histological studies and DNA fragmentation analysis also support the toxic effect of ATO in these organs pathophysiology. Post treatment with AA (at a dose of 20 mg/kg body weight for 4 days), however, reduced ATO-induced oxidative stress and suppressed all these apoptotic events. Results suggest that AA could effectively and extensively counteract these adverse effects and might protect liver and kidney from ATO-induced severe tissue toxicity.

Curcumin protects rat liver from streptozotocin-induced diabetic pathophysiology by counteracting reactive oxygen species and inhibiting the activation of p53 and MAPKs mediated stress response pathways

Curcumin (CUR) is a highly pleiotropic molecule and possesses anti-inflammatory, hypoglycemic, antioxidative, wound-healing and antimicrobial activities. The present study was carried out to investigate whether CUR plays any beneficial role in streptozotocin (STZ) induced hepatic pathophysiology in diabetic rats. STZ exposure increased hepatic damage associated serum markers (ALT, ALP and LDH) as well as NO production in the liver tissue. Moreover, the same exposure enhanced ROS generation and lipid peroxidation; reduced GSH levels and antioxidant enzyme activities. Hyperglycemia induced hepatic pathophysiology also activated stress response pathways (involving phosphorylation of p38, ERK1/2 MAPKs and p53) and reduced mitochondrial membrane potential which in turn led to cellular apoptosis as evidenced from increased hepatic DNA fragmentation as well as FACS analysis. However, treatment with CUR effectively counteracts diabetes-induced, oxidative stress mediated hepatic damage and could act as a therapeutic in lessening liver dysfunction in diabetic subjects.

Alleviative effect of quercetin on rat testis against arsenic: a histological and biochemical study

The preventive effect of quercetin on arsenic stimulated reproductive ailments in male Sprague Dawely (SD) rats was investigated. Twenty rats were divided into four groups. The first group served as a control and was provided tap water. The second group of rats was treated with sodium arsenite at the dose of 50 ppm in drinking water. The third group served as a positive control and received an oral dose of quercetin (50 mg/kg). In the fourth group, quercetin (50 mg/kg) was co-administered orally with arsenic (50 ppm in drinking water). All the treatments were carried out for 49 days. Arsenic treatment resulted in adverse morphological and histopathological changes in testis of rats including reduced epithelial height and tubular diameter, and increased luminal diameter. In contrast, these adverse effects of arsenic were eliminated by co-administration of quercetin. Additionally arsenic treatment significantly increased testicular thiobarbituric acid reactive substance (TBARS) levels while catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and glutathione reductase (GSR) activities, and plasma and intra-testicular testosterone concentrations, were decreased significantly. Lipid peroxidation (LPO) was significantly suppressed and depleted antioxidant defense mechanism was restored by the quercetin co-treatment. Also quercetin treatment resulted in a marked increase in plasma and testicular testosterone concentrations. On the basis of these findings, it was concluded that quercetin may be used as a potential therapeutic drug against arsenic induced reproductive toxicity.

Protective effects of melatonin against arsenic-induced apoptosis and oxidative stress in rat testes

This study aimed to investigate the protective effects of melatonin against arsenic-induced apoptosis and oxidative stress in rat testes. A total of 27 male rats were divided into 3 groups: control (saline: 5 ml kg−1 day−1, intragastrically), arsenic (sodium arsenite (NaAsO2): 5 mg kg−1 day−1, intragastrically), and arsenic + melatonin (sodium arsenite (NaAsO2): 5 mg kg−1 day−1, intragastrically and melatonin: 25 mg kg−1 day−1, intraperitoneally) group. At the end of 30 days, the rats were killed under anesthesia. Histopathological examination showed that testicular injury mediated by arsenic was ameliorated by the administration of melatonin. The number of apoptotic germ cell was increased, and the number of proliferating cell nuclear antigen (PCNA)-positive germ cell was decreased in testis after arsenic administration. Our data indicate a significant reduction in the activity of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, and there was a rise in the expression of PCNA in testis of arsenic + melatonin group. The decreased superoxide dismutase, catalase, and glutathione peroxidase activities as well as increased malondialdehyde levels in testis due to arsenic administration were also counteracted by melatonin. These data suggested that melatonin has beneficial effects against arsenic-induced testicular damage by decreasing morphological damage, germ cell apoptosis, lipid peroxidation, and oxidative stress. Our results suggest that melatonin plays a protective role against arsenic-induced testicular apoptosis and oxidative stress.

Oxidative stress: the mitochondria-dependent and mitochondria-independent pathways of apoptosis

Oxidative stress basically defines a condition in which prooxidant-antioxidant balance in the cell is disturbed; cellular biomolecules undergo severe oxidative damage, ultimately compromising cells viability. In recent years, a number of studies have shown that oxidative stress could cause cellular apoptosis via both the mitochondria-dependent and mitochondria-independent pathways. Since these pathways are directly related to the survival or death of various cell types in normal as well as pathophysiological situations, a clear picture of these pathways for various active molecules in their biological functions would help designing novel therapeutic strategy. This review highlights the basic mechanisms of ROS production and their sites of formation; detail mechanism of both mitochondria-dependent and mitochondria-independent pathways of apoptosis as well as their regulation by ROS. Emphasis has been given on the redox-sensitive ASK1 signalosome and its downstream JNK pathway. This review also describes the involvement of oxidative stress under various environmental toxin- and drug-induced organ pathophysiology and diabetes-mediated apoptosis. We believe that this review would provide useful information about the most recent progress in understanding the mechanism of oxidative stress-mediated regulation of apoptotic pathways. It will also help to figure out the complex cross-talks between these pathways and their modulations by oxidative stress. The literature will also shed a light on the blind alleys of this field to be explored. Finally, readers would know about the ROS-regulated and apoptosis-mediated organ pathophysiology which might help to find their probable remedies in future.

Mangiferin, a natural xanthone, protects murine liver in Pb(II) induced hepatic damage and cell death via MAP kinase, NF-κB and mitochondria dependent pathways

One of the most well-known naturally occurring environmental heavy metals, lead (Pb) has been reported to cause liver injury and cellular apoptosis by disturbing the prooxidant-antioxidant balance via oxidative stress. Several studies, on the other hand, reported that mangiferin, a naturally occurring xanthone, has been used for a broad range of therapeutic purposes. In the present study, we, therefore, investigated the molecular mechanisms of the protective action of mangiferin against lead-induced hepatic pathophysiology. Lead [Pb(II)] in the form of Pb(NO₃)₂ (at a dose of 5 mg/kg body weight, 6 days, orally) induced oxidative stress, hepatic dysfunction and cell death in murine liver. Post treatment of mangiferin at a dose of 100 mg/kg body weight (6 days, orally), on the other hand, diminished the formation of reactive oxygen species (ROS) and reduced the levels of serum marker enzymes [alanine aminotranferase (ALT) and alkaline phosphatase (ALP)]. Mangiferin also reduced Pb(II) induced alterations in antioxidant machineries, restored the mitochondrial membrane potential as well as mutual regulation of Bcl-2/Bax. Furthermore, mangiferin inhibited Pb(II)-induced activation of mitogen-activated protein kinases (MAPKs) (phospho-ERK 1/2, phosphor-JNK phospho- p38), nuclear translocation of NF-κB and apoptotic cell death as was evidenced by DNA fragmentation, FACS analysis and histological assessment. In vitro studies using hepatocytes as the working model also showed the protective effect of mangiferin in Pb(II) induced cytotoxicity. All these beneficial effects of mangiferin contributes to the considerable reduction of apoptotic hepatic cell death induced by Pb(II). Overall results demonstrate that mangiferin exhibit both antioxidative and antiapoptotic properties and protects the organ in Pb(II) induced hepatic dysfunction.

A 35 kD Phyllanthus niruri protein modulates iron mediated oxidative impairment to hepatocytes via the inhibition of ERKs, p38 MAPKs and activation of PI3k/Akt pathway

It has been reported that the herb, Phyllanthus niruri, possess antioxidant, anti-infection, anti-asthmatic, anti-diuretic, anti-soresis and many more beneficial activities. The goal of our present study was to evaluate the protective role of a 35 kD protein (PNP) isolated from this herb against iron-induced cytotoxicity in murine hepatocytes. Exposure of hepatocytes to iron (FeSO4) caused elevation of reactive oxygen species (ROS) production, enhanced lipid peroxidation and protein carbonylation, depleted glutathione levels, decreased the antioxidant power (FRAP) of the cells and reduced cell viability. Iron mediated cytotoxicity disrupted mitochondrial membrane potential (Δψm) and thereby caused apoptosis mainly by the intrinsic pathway via the down-regulation of IκBα with a concomitant up-regulation of NF-kB as well as the phosphorylation of ERKs and p38 MAP kinases. In addition, iron-induced cytotoxicity disrupted the normal balance of Bcl-2 family proteins in hepatocytes. Incubation of hepatocytes with PNP, however, protected the cells from apoptosis by stabilizing the mitochondria and arresting the release of cytochrome c. It also suppressed caspase activation and cleavage of PARP. Moreover, this protein has strong free radical scavenging activity and thereby scavenged ROS extensively. Combining all, results suggest that simultaneous treatment with PNP might suppress the iron-induced cytotoxicity in hepatocytes.

Arjunolic acid: a new multifunctional therapeutic promise of alternative medicine

IMPORTANCE OF THE FIELD

In recent years, a number of studies describing the effective therapeutic strategies of medicinal plants and their active constituents in traditional medicine have been reported. Indeed, tremendous demand for the development and implementation of these plant derived biomolecules in complementary and alternative medicine is increasing and appear to be promising candidates for pharmaceutical industrial research. These new molecules, especially those from natural resources, are considered as potential therapeutic targets, because they are derived from commonly consumed foodstuff and are considered to be safe for humans.

AREAS COVERED IN THIS REVIEW

This review highlights the beneficial role of arjunolic acid, a naturally occurring chiral triterpenoid saponin, in various organ pathophysiology and the underlying mechanism of its protective action. Studies on the biochemistry and pharmacology suggest the potential use of arjunolic acid as a novel promising therapeutic strategy.

WHAT THE READERS WILL GAIN

The multifunctional therapeutic application of arjunolic acid has already been documented by its various biological functions including antioxidant, anti-fungal, anti-bacterial, anticholinesterase, antitumor, antiasthmatic, wound healing and insect growth inhibitor activities. The scientific basis behind its therapeutic application as a cardioprotective agent in traditional medicine is justified by its ability to prevent myocardial necrosis and apoptosis, platelet aggregation, coagulation and lowering of blood pressure, heart rate, as well as cholesterol levels. Its antioxidant property coupled with metal chelating property (by its two hydroxyl groups) protects different organs from metal and drug-induced organ pathophysiology. Arjunolic acid also plays a beneficial role in the pathogenesis of diabetes and its associated complications. The mechanism of cytoprotection of arjunolic acid, at least in part, results from the detoxification of reactive oxygen species (ROS) produced in the respective pathophysiology. In addition to its other biological functions, it also possesses vibrant insecticidal properties and it has the potential to be used as a structural molecular framework for the design of molecular receptors in the general area of supramolecular chemistry and nanochemistry. Esters of arjunolic acid function as organogelators which has wide application in designing thermochromic switches and sensor devices. Arjunolic acid derived crown ether is an attractive candidate for the design of molecular receptors, biomimetics and supramolecular systems capable of performing some biological functions.

HOME MESSAGE

This review would provide useful information about the recent progress of natural product research in the domain of clinical science. This review also aims to untie the multifunctional therapeutic application of arjunolic acid, a nanometer-long naturally occurring chiral triterpenoid biomolecule.

Iron induces hepatocytes death via MAPK activation and mitochondria-dependent apoptotic pathway: beneficial role of glycine

In the present study we investigated the beneficial role of glycine in iron (FeSO₄) induced oxidative damage in murine hepatocytes. Exposure of hepatocytes to 20 μM FeSO₄ for 3 hours enhanced reactive oxygen species (ROS) generation and induced alteration in biochemical parameters related to hepatic oxidative stress. Investigating cell signalling pathway, we observed that iron (FeSO₄) intoxication caused NF-κB activation as well as the phosphorylation of p38 and ERK MAPKs. Iron (FeSO₄) administration also disrupted Bcl-2/Bad protein balance, reduced mitochondrial membrane potential, released cytochrome c and induced the activation of caspases and cleavage of PARP protein. Flow cytometric analysis also confirmed that iron (FeSO₄) induced hepatocytes death is apoptotic in nature. Glycine (10 mM) supplementation, on the other hand, reduced all the iron (FeSO₄) induced apoptotic indices. Combining, results suggest that glycine could be a beneficial agent against iron mediated toxicity in hepatocytes.