Phenylarsine oxide (PAO) is a known environmental pollutant and skin keratinocytes are most seriously affected. Baicalin (BCN) was reported to have antioxidant and anti-inflammatory effects, but its protective effect against PAO toxicity is unknown. This study aimed at exploring whether baicalin can reverse the toxicity of human epidermal keratinocytes that are subjected to PAO exposure and underlying mechanisms. In silico analysis from a publicly accessible HaCaT cell transcriptome dataset exposed to chronic Arsenic showed significant differential expression of several genes, including the genes related to DNA replication. Later, we performed in vitro experiments, in which HaCaT cells were exposed to PAO (500 nM) in the existence of BCN (10-50 µM). Treatment of PAO alone induces the JNK, p38 and caspase-3 activation, which were engaged in the apoptosis induction, while the activity of AKT was significantly inhibited, which was engaged in the suppression of apoptosis. PAO suppressed SIRT3 expression and induced intracellular reactive oxygen species (ROS), causing a marked reduce in cell viability and apoptosis. However, BCN treatment restored the PAO-induced suppression of SIRT3 and AKT expression, reduced intracellular ROS generation, and markedly suppressed both caspase-3 activation and apoptosis induction. However, the protective effect of BCN was significantly attenuated after pretreatment with nicotinamide, an inhibitor of SIRT3. These findings indicate that BCN protects against cell death induced by PAO via inhibiting excessive intracellular ROS generation via restoring SIRT3 activity and reactivating downstream AKT pathway. In this study, we firstly shown that BCN is an efficient drug to prevent PAO-induced skin cytotoxicity, and these findings need to be confirmed by in vivo and clinical investigations.

CONCLUSIONS: Serendipita indica induced metabolic reprogramming in colonized plants complements phosphorus-management in improving their tolerance to arsenic stress on multifaceted biological fronts. Restoration of the anthropic damage done to our environment is inextricably linked to devising strategies that are not only economically sound but are self-renewing and ecologically conscious. The dilemma of heavy metal (HM) dietary ingestion, especially arsenic (As), faced by humans and animals alike, necessitates the exploitation of such technologies and the cultivation of healthy and abundant crops. The remarkable symbiotic alliance between plants and \'mycorrhizas\' has evolved across eons, benefiting growth/yield aspects as well as imparting abiotic/biotic stress tolerance. The intricate interdependence of Serendipita indica (S. indica) and rice plant reportedly reduce As accumulation, accentuating the interest of microbiologists, agriculturists, and ecotoxicological scientists apropos of the remediation mechanisms of As in the soil-AMF-rice system. Nutrient management, particularly of phosphorus (P), is also praised for mitigating As phytotoxicity by deterring the uptake of As molecules due to the rhizospheric cationic competition. Taking into consideration the reasonable prospects of success in minimizing As acquisition by rice plants, this review focuses on the physiological, metabolic, and transcriptional alterations underlying S. indica symbiosis, recuperation of As stress together with nutritional management of P by gathering case studies and presenting successful paradigms. Weaving together a volume of literature, we assess the chemical forms of As and related transport pathways, discuss As-P-rice interaction and the significance of fungi in As toxicity mitigation, predominantly the role of mycorrhiza, as well as survey of the multifaceted impacts of S. indica on plants. A potential strategy for simultaneous S. indica + P administration in paddy fields is proposed, followed by future research orientation to expand theoretic comprehension and encourage field-based implementation.

Arsenic (As) is a widespread metalloid with well-known toxicity. To date, numerous studies have focused on individual level toxicity (e.g., growth and reproduction) of As to typical invertebrate springtails in soils, however, the molecular level toxicity and mechanism was poorly understood. Here, an integrated transcriptomics and metabolomics approach was used to reveal responses of Folsomia candida exposed to As(V) of 10 and 60 mg kg-1 at which the individual level endpoints were influenced. Transcriptomics identified 5349 and 4020 differentially expressed genes (DEGs) in low and high concentration groups, respectively, and the most DEGs were down-regulated. Enrichment analysis showed that low and high concentrations of As(V) significantly inhibited chromatin/chromosome-related biological processes (chromatin/chromosome organization, nucleosome assembly and organization, etc.) in springtails. At high concentration treatment, structural constituent of cuticle, chitin metabolic process and peptidase activity (serine-type peptidase activity, endopeptidase activity, etc.) were inhibited or disturbed. Moreover, the apoptosis pathway was significantly induced. Metabolomics analysis identified 271 differential changed metabolites (DCMs) in springtails exposed to high concentration of As. Steroid hormone biosynthesis was the most significantly affected pathway. Several DCMs that related to chitin metabolism could further support above transcriptomic results. These findings further extended the knowledge of As toxic mechanisms to soil fauna and offer important information for the environmental risk assessment.

In nature, arsenic is mostly found in the form of inorganic compounds. Inorganic arsenic compounds have a variety of uses and are currently used in the manufacture of pesticides, preservatives, pharmaceuticals, etc. While inorganic arsenic is widely used, arsenic pollution is increasing worldwide. Public hazards caused by arsenic contamination of drinking water and soil are becoming increasingly evident. Epidemiological and experimental studies have linked inorganic arsenic exposure to the development of many diseases, including cognitive impairment, cardiovascular failure, cancer, etc. Several mechanisms have been proposed to explain the effects caused by arsenic, such as oxidative damage, DNA methylation, and protein misfolding. Understanding the toxicology and potential molecular mechanisms of arsenic can help mitigate its harmful effects. Therefore, this paper reviews the multiple organ toxicity of inorganic arsenic in animals, focusing on the various toxicity mechanisms of arsenic-induced diseases in animals. In addition, we have summarized several drugs that can have therapeutic effects on arsenic poisoning in pursuit of reducing the harm of arsenic contamination from different pathways.

In the context of eco-sustainable acquisition of food security, arsenic (As) acts as a deterring factor, which easily infiltrates our food chain via plant uptake. Therefore, devising climate-smart strategies becomes exigent for minimizing the imposed risks. Pertinently, Serendipita indica (S. indica) is well reputed for its post-symbiotic stress alleviatory and phyto-promotive potential. Management of phosphorus (P) is acclaimed for mitigating arsenic toxicity in plants by inhibiting the uptake of As molecules due to the competitive cationic exchange in the rhizosphere. The current study was designed to investigate the tandem effects of S. indica and P in combating As toxicity employing two rice genotypes, i.e., Guodao-6 (GD-6; As-sensitive genotype) and Zhongzhe You-1 (ZZY-1; As-tolerant genotype). After successful fungal colonization, alone and combined arsenic (10  μ M L-1) and phosphorus (50  μ M L-1) treatments were applied. Results displayed that the recuperating effects of combined S. indica and P treatment were indeed much profound than their alone treatments; however, most of the beneficial influences were harnessed by ZZY-1 in comparison with GD-6. Distinct genotypic differences were observed for antioxidant enzyme activities, which were induced slightly higher in S. indica-colonized ZZY-1 plants, with or without additional P, as compared to GD-6. Ultrastructure images of root and shoot exhibited ravages of As in the form of chloroplasts-, nuclei-and cell wall-damage with enlarged vacuole area, mellowed mostly by the combined treatment of S. indica and P in both genotypes. Gene expression of PHTs family transporters was regulated at different levels in almost all treatments across genotypes. Conclusively, the results of this study validated the promising role of S. indica and additional P in mitigating As stress, albeit corroborated that the extent of relevant benefit exploitation is highly genotype-dependent. Verily, unlocking the potential of nature-friendly solutions will mend the anthropogenic damage already been done to our environment.

Arsenic pollution in freshwater poses a serious threat to aquatic organisms. However, dissolved organic matter (DOM) in water can modulate arsenic environmental toxicity by either suppressing or promoting its bioaccumulation. In this study, we investigated the toxicity, bioaccumulation, and biotransformation of inorganic arsenic (arsenite AsIII and arsenate AsV) combined with two types of DOM, i.e., humic acid (HA) and fulvic acid (FA), in the algae Chlamydomonas reinhardtii and Ochromonas danica. C. reinhardtii has a cell wall and cannot bioaccumulate arsenic complexation, whereas O. danica has no cell wall. Without DOM, AsV was more toxic than AsIII for C. reinhardtii, and AsV was less toxic than AsIII for O. danica. HA and FA addition reduced AsV and AsIII toxicities; the larger molecular weight (Mw) of HA contributed to the reduction in toxicity to an even greater extent, and reduced arsenic accumulation while promoting the biotransformation ability of C. reinhardtii, which has a cell wall. However, HA and FA addition increased AsV and AsIII toxicities and arsenic accumulation while relatively enhancing the biotransformation ability of O. danica, which has no cell wall. Coupling toxicity, bioaccumulation, and biotransformation, DOM (HA and FA) contributed to the altered toxicity of freshwater algae to AsV and AsIII through reduced/increased arsenic accumulation and enhanced biotransformation. Overall, our study considered the combined toxicity of inorganic arsenic and DOM in phytoplankton, helping estimate the potential environmental risk of arsenic in aqueous environments.

Metalloid contamination in the environment is one of the serious concerns posing threat to our ecosystems. Excess of metalloid concentrations (including antimony, arsenic, boron, selenium etc.) in soil results in their over accumulation in plant tissues, which ultimately causes phytotoxicity and their bio-magnification. So, it is very important to find some ecofriendly approaches to counter negative impacts of above mentioned metalloids on plant system. Brassinosteroids (BRs) belong to family of plant steroidal hormones, and are considered as one of the ecofriendly way to counter metalloid phytotoxicity. This phytohormone regulates the plant biology in presence of metalloids by modulating various key biological processes like cell signaling, primary and secondary metabolism, bio-molecule crosstalk and redox homeostasis. The present review explains the in-depth mechanisms of BR regulated plant responses in presence of metalloids, and provides some biotechnological aspects towards ecofriendly management of metalloid contamination.

Rice remains a major staple food source for the rapidly growing world population. However, regular occurrences of carcinogenic arsenic (As) minerals in waterlogged paddy topsoil pose a great threat to rice production and consumers across the globe. Although As contamination in rice has been well recognized over the past two decades, no suitable rice germplasm had been identified to exploit in adaptive breeding programs. Therefore, this current study identified suitable rice germplasm for As tolerance and exclusion based on a variety of traits and investigated the interlinkages of favorable traits during different growth stages. Fifty-three different genotypes were systematically evaluated for As tolerance and accumulation. A germination screening assay was carried out to identify the ability of individual germplasm to germinate under varying As stress. Seedling-stage screening was conducted in hydroponics under varying As stress to identify tolerant and excluder genotypes, and a field experiment was carried out to identify genotypes accumulating less As in grain. Irrespective of the rice genotypes, plant health declined significantly with increasing As in the treatment. However, genotype-dependent variation in germination, tolerance, and As accumulation was observed among the genotypes. Some genotypes (WTR1-BRRI dhan69, NPT-IR68552-55-3-2, OM997, and GSR IR1-5-Y4-S1-Y1) showed high tolerance by excluding As in the shoot system. Arsenic content in grain ranged from 0.12 mg kg-1 in Huang-Hua-Zhan (indica) from China to 0.48 mg kg-1 in IRAT 109 (japonica) from Brazil. This current study provides novel insights into the performance of rice genotypes under varying As stress during different growth stages for further use in ongoing breeding programs for the development of As-excluding rice varieties for As-polluted environments.

In different regions of the world, arsenic (As) contaminated soils poses a serious threat to plant growth and its physiological processes. Organic amendments are a cost-effective and environmentally friendly way to improve plant growth under stress conditions in contaminated soils. In As polluted acidic ultisol, a greenhouse trial was conducted to investigate the protective effects of peanut straw biochar (PSB) and canola straw biochar (CSB) on soybean mineral nutrition, antioxidant enzymes, and physiological growth parameters. The current study used eighteen treatments with different levels of As ((1) 0 mg kg-1, (2) 30 mg kg-1, (3) 60 mg kg-1) and biochar (PSB and CSB) (0%, 1%, and 2%). The result suggests that biochar addition under As stress in highly weathered acidic ultisol soil increased soybean growth attributes and defense mechanisms. The PSB was more effective than the CSB in a dose-dependent manner. The application of 2% PSB in polluted soil resulted in significant increases in soybean height (58%), biomass production (root (44%) and shoot length (52%)), chlorophyll contents (92%), soybean functional leaves (62%), total soluble sugars (TSS) (71%) and base cations (Ca2+, Mg2+, K+, Na+). However, biochar application decreased proline, MDA, H2O2, and O2- by 64%, 82%, 49%, and 45% respectively. Furthermore, biochar application increased (Phosphate) P and As uptake in soybean, with PSB application exhibiting a greater increase than CSB application. As a result, crop straw-derived biochar can reduce As-induced soybean plant damage and insert a protective effect in As-contaminated acidic ultisol soils.

Arsenic (As), a widespread environmental contaminant, can induce serious male reproductive injury; however, the underlying mechanisms remain unclear. Multi-omics analyses, including transcriptome, proteome, and phosphoproteome could promote our understanding of As-induced male reproductive toxicity. Here, we established the reproductive injured mice model by intraperitoneal injection of NaAsO2 (8 mg/kg body weight), which was validated by reduced reproductive cells, sperm motility, and litter size. The followed multi-omics analyses of mice revealed that As exposure inhibited ATP production by decreasing the expression of proteins HK1, and GAPDHS, and the enzymatic activities of PDH and SDH. The inhibition of mitochondrial activity and increase in HDAC2 and MTA3 dysregulated the lysine acetylation levels of histone and global proteins. Specifically, the downregulated histones H4K5ac and H4K12ac and upregulated histone H3K9ac disordered the distribution of TP1 to interfere with spermatogenesis. Moreover, As could reduce the expression of COL1A1, RAB13, and LSR to disrupt the junctions between seminiferous tubules, and thereinto, the inhibition of RAB13 increased PKA-dependent phosphorylation. Our study reveals that As causes male reproductive toxicity through decreasing energy production, altering histone acetylation, and impairing cell junctions. Our findings provide basic data for further studies on As reproductive toxicity.