Prolonged monocrotophos intake induces cardiac oxidative stress and myocardial damage in rats

Gut microbial metalloproteins and its role in xenobiotics degradation and ROS scavenging

The gut microbial metalloenzymes play an important role in maintaining the balance between gut microbial ecosystem, human physiologically processes and immune system. The metals coordinated into active site contribute in various detoxification and defense strategies to avoid unfavourable environment and ensure bacterial survival in human gut. Metallo-β-lactamase is a potent degrader of antibiotics present in periplasmic space of both commensals and pathogenic bacteria. The resistance to anti-microbial agents developed in this enzyme is one of the global threats for human health. The organophosphorus eliminator, organophosphorus hydrolases have evolved over a course of time to hydrolyze toxic organophosphorus compounds and decrease its effect on human health. Further, the redox stress responders namely superoxide dismutase and catalase are key metalloenzymes in reducing both endogenous and exogenous oxidative stress. They hold a great importance for pathogens as they contribute in pathogenesis in human gut along with reduction of oxidative stress. The in-silico study on these enzymes reveals the importance of point mutation for the evolution of these enzymes in order to enhance their enzyme activity and stability. Various mutation studies were conducted to investigate the catalytic activity of these enzymes. By using the "directed evolution" method, the enzymes involved in detoxification and defense system can be engineered to produce new variants with enhance catalytic features, which may be used to predict the severity due to multi-drug resistance and degradation pattern of organophosphorus compounds in human gut.

Indole-3 acetic acid induced cardiac hypertrophy in Wistar albino rats

Indole-3-acetic acid (IAA) is the most widely utilized plant growth regulator. Despite its extensive usage, IAA is often overlooked as an environmental pollutant. Due to its protein-binding nature, it also functions as a uremic toxin, contributing to its association with chronic kidney disease (CKD). While in vitro and epidemiological research have demonstrated this association, the precise impact of IAA on cardiovascular disease in animal models is unknown. The main objective of this study is to conduct a mechanistic analysis of the cardiotoxic effects caused by IAA using male Wistar albino rats as the experimental model. Three different concentrations of IAA (125, 250, 500 mg/kg) were administered for 28 days. The circulating IAA concentration mimicked previously observed levels in CKD patients. The administration of IAA led to a notable augmentation in heart size and heart-to-body weight ratio, indicating cardiac hypertrophy. Echocardiographic assessments supported these observations, revealing myocardial thickening. Biochemical and gene expression analyses further corroborated the cardiotoxic effects of IAA. Dyslipidemia, increased serum c-Troponin-I levels, decreased SOD and CAT levels, and elevated lipid peroxidation in cardiac tissue were identified. Moreover, increased expression of cardiac inflammatory biomarkers, including ANP, BNP, β-MHC, Col-III, TNF-α, and NF-κB, was also found in the IAA-treated animals. Histopathological analysis confirmed the cardiotoxic nature of IAA, providing additional evidence of its adverse effects on cardiovascular health. These results offer insights into the potential negative impact of IAA on cardiovascular function, and elucidating the underlying mechanisms of its cardiotoxicity.

The Protective Effect of Curcumin Against Cardiotoxic Effects Induced by Chronic Exposure to Chlorpyrifos

AIMS

This study aimed to evaluate the effect of Chlorpyrifos (CPF) in rat heart tissue and the effect of Curcumin (Cur) on cardiac enzymes, oxidative indices, and histopathological changes in the cardiac tissue.

BACKGROUND

CPF, the most used organophosphorus pesticide (OP), has been reported to induce cardiotoxic effects.

OBJECTIVE

The cardioprotective effects of Cur against CPF-induced toxicity have not been entirely investigated till now.

METHOD

Forty male Wistar rats were randomized into five groups (n=8). C group (Control animals that received olive oil), CPF group (10 mg/kg/day), CPF + Cur 25, CPF + Cur 50, and CPF + Cur 100 groups (animals received 10 mg/kg/day CPF and 25, 50, and 100 mg/kg Cur, respectively). All treatments were administered via oral gavage for 90 days. Cardiac enzymes (LDH & CPK) and oxidative stress (OS) biomarkers in heart tissue (malondialdehyde, Superoxide Dismutase) were measured. Histopathological changes in the heart tissue were also evaluated.

RESULT

Chronic exposure to CPF significantly increased cardiac enzyme levels and OS biomarkers. Histological changes were found, including disorganization of the cardiac muscle fibers with disorganization and degeneration in myocardial fibers with separation of myofibrils and cytoplasmic vacuolization of cardiac muscle fibers. Administration of Cur (100 mg/kg) reversed serum LDH concentration and OS biomarkers to normal levels in CPF-exposed animals (p < 0.05) and significantly improved cardiac damage.

CONCLUSION

According to the results of this study, Cur can reduce the adverse effects of long-term exposure to CPF in rat heart tissue by modulating OS.

Synergistic action of organophosphates and COVID-19 on inflammation, oxidative stress, and renin-angiotensin system can amplify the risk of cardiovascular maladies

Organophosphates (OPs) are ubiquitous environmental contaminants, widely used as pesticides in agricultural fields. In addition, they serve as flame-retardants, plasticizers, antifoaming or antiwear agents in lacquers, hydraulic fluids, and floor polishing agents. Therefore, world-wide and massive application of these compounds have increased the risk of unintentional exposure to non-targets including the human beings. OPs are neurotoxic agents as they inhibit the activity of acetylcholinesterase at synaptic cleft. Moreover, they can fuel cardiovascular issues in the form of myocardities, cardiac oedema, arrhythmia, systolic malfunction, infarction, and altered electrophysiology. Such pathological outcomes might increase the severity of cardiovascular diseases which are the leading cause of mortality in the developing world. Coronavirus disease-19 (COVID-19) is the ongoing global health emergency caused by SARS-CoV-2 infection. Similar to OPs, SARS-CoV-2 disrupts cytokine homeostasis, redox-balance, and angiotensin-II/AT₁R axis to promote cardiovascular injuries. Therefore, during the current pandemic milieu, unintentional exposure to OPs through several environmental sources could escalate cardiac maladies in patients with COVID-19.

N-Acetylcysteine Reverses Monocrotophos Exposure-Induced Hepatic Oxidative Damage via Mitigating Apoptosis, Inflammation and Structural Changes in Rats

Oxidative stress-mediated tissue damage is primarily involved in hepatic injuries and dysfunctioning. Natural antioxidants have been shown to exert hepatoprotective, anti-inflammatory and antiapoptotic properties. The present study evaluated the effect of N-acetylcysteine (NAC) against monocrotophos (MCP) exposure-induced toxicity in the rat liver. Albino Wistar rats were divided into four groups: (1) control, (2) NAC-treated, (3) MCP-exposure, (4) NAC and MCP-coexposure group. The dose of MCP (0.9 mg/kg b.wt) and NAC (200 mg/kg b.wt) were administered orally for 28 days. Exposure to MCP caused a significant increase in lipid peroxidation, protein oxidation and decreased glutathione content along with the depletion of antioxidant enzyme activities. Further MCP exposure increased pro-inflammatory cytokines levels and upregulated Bax and Caspase-3 expressions. MCP exposure also caused an array of structural alternations in liver tissue, as depicted by the histological and electron microscopic analysis. Thepretreatment of NAC improved glutathione content, restored antioxidant enzyme activities, prevented oxidation of lipids and proteins, decreased pro-inflammatory cytokines levels and normalized apoptotic protein expression. Treatment of NAC also prevented histological and ultrastructural alternations. Thus, the study represents the therapeutic efficacy and antioxidant potential of NAC against MCP exposure in the rat liver.

Protective effects of lutein against vancomycin-induced acute renal injury in mice via upregulation of peroxisome proliferator-activated receptor gamma/nuclear factor erythroid 2-related factor 2 and inhibition nuclear factor-kappaB/caspase 3

Vancomycin, an antibiotic used occasionally as a last line of treatment for methicillin-resistant Staphylococcus aureus, is reportedly associated with nephrotoxicity. This study aimed at evaluating the protective effects of lutein against vancomycin-induced acute renal injury. Peroxisome proliferator-activated receptor gamma (PPARγ) and its associated role in renoprotection by lutein was also examined. Male BALB/c mice were divided into six treatment groups: control with normal saline, lutein (200 mg/kg), vancomycin (250 mg/kg), vancomycin (500 mg/kg), vancomycin (250 mg/kg) with lutein, and vancomycin (500 mg/kg) with lutein groups; they were euthanized after 7 days of treatment. Thereafter, samples of blood, urine, and kidney tissue of the mice were analyzed, followed by the determination of levels of N-acetyl-β-D-glucosaminidase (NAG) in the urine, renal creatine kinase; protein carbonyl, malondialdehyde, and caspase-3 in the kidney; and the expression of PPARγ, nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear factor-kappaB (NF-κB) in renal tissue. Results showed that the levels of protein carbonyl and malondialdehyde, and the activity of NAG, creatine kinase and caspase-3, were significantly increased in the vancomycin-treatment groups. Moreover, the levels of Nrf2 significantly decreased, while NF-κB expression increased. Lutein ameliorated these effects, and significantly increased PPARγ expression. Furthermore, it attenuated vancomycin-induced histological alterations such as, tissue necrosis and hypertrophy. Therefore, we conclude that lutein protects against vancomycin-induced renal injury by potentially upregulating PPARγ/Nrf2 expression in the renal tissues, and consequently downregulating the pathways: inflammation by NF-κB and apoptosis by caspase-3.

Serum High-sensitivity C-reactive Protein Level and Corrected QT Interval in Agricultural Workers in Myanmar Exposed to Chronic Occupational Organophosphate Pesticides

Although acute organophosphate (OP) pesticide poisoning is associated with the risk cardiovascular diseases (CVD), the association between chronic occupational OP pesticide exposure and CVD risk is limited. We investigated serum high-sensitivity C-reactive protein (hs-CRP) levels and QTc intervals in 45 agricultural workers who were chronically exposed to OP pesticides and 45 non-exposed subjects. Serum hs-CRP level was determined by enzyme-linked immunosorbent assay (ELISA) and a level >1.0 mg/l was regarded as CVD risk. The QT interval was measured by routine 12-lead Electrocardiogram (ECG) with Lead II rhythm, and QTc was calculated. The median value of the serum hs-CRP level [1.20 (0.67-2.38) vs 0.74 (0.41-1.17) mg/l, P <0.05] and the mean QTc interval (422.71 ± 23.73 vs 396.27 ± 18.48 ms, P <0.0001) was significantly higher in the OP pesticide exposed subjects. Pesticide exposure was significantly associated with CVD risk (Chi-Square χ² = 6.480, P = 0.011) and QTc interval prolongation (χ² = 13.846, P <0.001). A higher risk of CVD (odds ratio = 3.030; 95% confidence interval = 1.276 - 7.197) was observed in the OP pesticide exposed subjects. This study suggested that OP pesticide exposure should be considered as one of the significant risk factors for CVDs.

Dichlorvos Resistance in the House Fly Populations, Musca domestica, of Iranian Cattle Farms

Background:

Insecticide resistance is one of the most important problems associated with the control of Musca domestica, due to the potential of the rapid development of resistance to different chemical insecticides. The present study was carried out to evaluate dichlorvos resistance in the house fly populations collected from central regions of Iran, Isfahan Province and Chaharmahal and Bakhtiari Province, during 2017 to 2019.

Methods:

Bioassays were carried out using a standard topical application method as well as a fumigation method. The Koohrang population (susceptible) with the lowest LD₅₀ values to dichlorvos was chosen to calculate the resistance ratios (RR). Altered sensitivity of acetylcholinesterase (AChE), a target enzyme for dichlorvos, was investigated.

Results:

According to the results, very high levels of dichlorvos resistance were observed in the Mobarake population (RR= 80.25-fold by topical application and 33-fold by fumigation bioassay), and Isfahan population (RR= 107.30-fold by topical application and 43-fold by fumigation bioassay) compared to the Koohrang population. Acetylcholinesterase of the Koohrang population was the most sensitive to inhibition by dichlorvos based on the determination of median inhibitory concentration (IC₅₀), but AChE of Mobarake and Isfahan populations were 741.93- and 343.94- fold less sensitive to inhibition.

Conclusion:

The insensitivity of AChE was possibly involved in dichlorvos resistance in the house fly populations.

Tebuconazole induced oxidative stress and histopathological alterations in adult rat heart

TEB belongs to the family of triazole fungicides and it is used to protect agricultural crop plants from fungal pathogens. The information regarding its cardiotoxic effects through different pathways particularly by perturbing the oxidative balance and causing damage to the myocardium is still limited. In the present study, oxidative and histopathologic damages caused by TEB in the cardiac tissue of male adult rats, were evaluated. Rats were exposed orally to TEB at 0.9, 9, 27 and 45 mg/kg b.w. for 28 days. Results showed that following TEB treatment malondialdehyde (MDA), protein carbonyl (PC), advanced oxidation protein product (AOPP), antioxidant enzyme activities (GPx and GR) and GSSG levels increased, while GSH levels and thus the GSH/GSSG ratio decreased. Superoxide dismutase (SOD) and catalase (CAT) initially increased at the doses of 0.9, 9 and 27 mg/kg b.w. and then decreased at the dose of 45 mg/kg b.w. Moreover, western blot analysis showed that TEB increased SOD1, CAT and HSP70 protein levels after 24 h. Furthermore, TEB induced various histological changes in the myocardium, including leucocytic infiltration, hemorrhage congestion of cardiac blood vessels and cytoplasmic vacuolization. Therefore, our investigation revealed, that TEB exhibits cardiotoxic effects by changing oxidative balance and damaging the cardiac tissue.

Association of co-accumulation of arsenic and organophosphate insecticides with diabetes and atherosclerosis in a rural agricultural community: KMCH-NNCD-I study

AIMS

In last few decades, the prevalence of diabetes and vascular diseases has intensified concurrently with increased use of synthetic chemicals in agriculture. This study is aimed to evaluate the association of co-accumulation of arsenic and organophosphate (OP) insecticides with diabetes and atherosclerosis prevalence in a rural Indian population.

METHODS

This study included observations from KMCH-NNCD-I (2015) cross-sectional study (n = 865) from an Indian farming village. The participants had assessment of clinical parameters including HbA_1c and carotid intima-media thickness and urinary heavy metals. Serum OP residues were extracted and quantified by GC-MS. Statistical analyses were performed to unravel the co-association of arsenic and OPs on prevalence of diabetes and atherosclerosis.

RESULTS

On multivariate regression analyses, total organophosphate level and arsenic accumulation showed association with diabetes and atherosclerosis. Higher odds ratio with significant trends were observed for the sub-quartiles formed by the combination of higher quartiles of arsenic and total organophosphates in association with diabetes and atherosclerosis.

CONCLUSIONS

We observed evidence of possible synergism between arsenic and OPs in association with prevalence of diabetes, pre-diabetes and atherosclerosis in the study population. Our findings highlight the importance of understanding health effects of mixed exposures and raises vital questions on the role of these agrochemicals in the etiology of diabetes and vascular diseases.

Mediation of oxidative stress toxicity induced by pyrethroid pesticides in fish

Organophosphate and organochlorine pesticides are banned in most countries because they cause high toxicity and bioaccumulation in non-target organisms. Pyrethroid pesticides have been applied to agriculture and aquaculture since the 1970s to replace traditional pesticides. However, pyrethroids are approximately 1000 times more toxic to fish than to mammals and birds. Fish-specific organs such as the gills and their late metabolic action against this type of pesticide make fish highly susceptible to the toxicity of pyrethroid pesticides. Oxidative stress plays an important role in the neurological, reproductive, and developmental toxicity caused by pyrethroids. Deltamethrin, cypermethrin, and lambda-cyhalothrin are representative pyrethroid pesticides that induce oxidative stress in tissues such as the gills, liver, and muscles of fish and cause histopathological changes. Although they are observed in low concentrations in aquatic environments such as rivers, lakes, and surface water they induce DNA damage and apoptosis in fish. Pyrethroid pesticides cause ROS-mediated oxidative stress in fish species including carp, tilapia, and trout. They also cause lipid peroxidation and alter the state of DNA, proteins, and lipids in the cells of fish. Moreover, changes in antioxidant enzyme activity following pyrethroid pesticide exposure make fish more susceptible to oxidative stress caused by environmental pollutants. In this review, we examine the occurrence of pyrethroid pesticides in the aquatic environment and oxidative stress-induced toxicity in fish exposed to pyrethroids.

The Interplay between Immune System and Microbiota in Diabetes

Diabetes is not a single and homogeneous disease, but a cluster of metabolic diseases characterized by the common feature of hyperglycemia. The pathogenesis of type 1 diabetes (T1D) and type 2 diabetes (T2D) (and all other intermediate forms of diabetes) involves the immune system, in terms of inflammation and autoimmunity. The past decades have seen an increase in all types of diabetes, accompanied by changes in eating habits and consequently a structural evolution of gut microbiota. It is likely that all these events could be related and that gut microbiota alterations might be involved in the immunomodulation of diabetes. Thus, gut microbiota seems to have a direct, even causative role in mediating connections between the environment, food intake, and chronic disease. As many conditions that increase the risk of diabetes modulate gut microbiota composition, it is likely that immune-mediated reactions, induced by alterations in the composition of the microbiota, can act as facilitators for the onset of diabetes in predisposed subjects. In this review, we summarize recent evidence in the field of gut microbiota and the role of the latter in modulating the immune reactions involved in the pathogenesis of diabetes.

Monocyte Chemoattractant Protein-1-Induced Protein in Age-Related Atrial Fibrillation and Its Association with Circulating Fibrosis Biomarkers

BACKGROUND

Atrial fibrillation (AF), for which age is an independent risk factor, is the most common persistent arrhythmia. Monocyte chemoattractant protein-1-induced protein (MCPIP), a transcription factor that induces a series of inflammation and cell death procedures, has been indicated to cause cardiomyocyte death in ischemic cardiomyopathy. The objective of this research was to investigate the relationship between age-related AF and MCPIP.

METHODS

A total of 1,084 participants were included in this study, including 542 AF patients and 542 non-AF controls. Their medical histories were collected and analyzed. Moreover, blood samples were collected, and ELISA tests for expression of the inflammatory factor MCPIP and the fibrosis biomarkers pro-collagen type III N-terminal peptide (PIIINP) and type I collagen C-terminal telopeptide (ICTP) were conducted. Finally, a correlation analysis of these inflammatory factors and biomarkers was performed based on the ELISA results.

RESULTS

We compared the echocardiography results of AF patients and found that the left ventricular ejection fraction and left atrial appendage velocity decreased with age (p < 0.05). Moreover, ELISA analysis of these samples showed that the expression of MCPIP was the highest in elderly patients with AF (p < 0.05), and there was no significant difference in expression between adult AF patients and elderly controls (p > 0.05). Finally, the correlation analysis demonstrated that the expressions of MCPIP, PIIINP, and ICTP were positively correlated in the elderly AF patient group, the adult AF group, and the elderly control group (p < 0.05).

CONCLUSION

MCPIP expression was higher in age-related AF than in the other patient groups and it was associated with AF-induced fibrosis.

Pesticides and cardiotoxicity. Where do we stand?

Cardiovascular diseases are among the most significant causes of mortality in humans. Pesticides toxicity and risk for human health are controlled at a European level through a well-developed regulatory network, but cardiotoxicity is not described as a separate hazard class. Specific classification criteria should be developed within the frame of Regulation (EC) No 1272/2008 in order to classify chemicals as cardiotoxic, if applicable to avoid long-term cardiovascular complications. The aim of this study was to review the cardiac pathology and function impairment due to exposure to pesticides (i.e. organophosphates, organothiophisphates, organochlorines, carbamates, pyrethroids, dipyridyl herbicides, triazoles, triazines) based on both animal and human data. The majority of human data on cardiotoxicity of pesticides come from poisoning cases and epidemiological data. Several cardiovascular complications have been reported in animal models including electrocardiogram abnormalities, myocardial infarction, impaired systolic and diastolic performance, functional remodeling and histopathological findings, such as haemorrhage, vacuolisation, signs of apoptosis and degeneration.

Effects of microRNA-292-5p on myocardial ischemia-reperfusion injury through the peroxisome proliferator-activated receptor-α/-γ signaling pathway

Ischemia-reperfusion injury (IRI) is a major cause of cardiac damage following various pathological processes, such as free radical damage and cell apoptosis. This study aims to investigate whether microRNA-292-5p (miR-292-5p) protects against myocardial ischemia-reperfusion injury (IRI) via the peroxisome proliferator-activated receptor (PPAR)-α/-γ signaling pathway in myocardial IRI mice models. Mouse models of myocardial IRI were established. Adult male C57BL/6 mice were divided into different groups. The hemodynamic indexes, levels of related inflammatory factors and serum myocardial enzymes, and malondialdehyde (MDA) content and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were detected. The 2,3,5-triphenyltetrazolium chloride (TTC) staining was applied to determine infarct size. TUNEL staining was used to detect cardiomyocyte apoptosis. RT-qPCR and western blotting were performed to measure the related gene expressions. Compared with the model group and the T0070907 + miR-292-5p inhibitor, the miR-292-5p inhibitor group exhibited decreased incidence and duration time of ventricular tachycardia and ventricular fibrillation, serum myocardial enzymes, TNF-α, IL-6, IL-1β, MDA, cardiomyocyte apoptosis, expressions of Bax and p53 in addition to increased SOD and GSH-Px activity, and increased expressions of Bcl-2, PPARα, PPARγ, PLIN5, AQP7, and PCK1. The T0070907 group exhibited opposite results compared to the miR-292-5p inhibitor group. The results indicate that miR-292-5p downregulation protects against myocardial IRI through activation of the PPAR-α/PPAR-γ signaling pathway.

C. elegans as a model in developmental neurotoxicology

Due to many advantages Caenorhabditis elegans (C. elegans) has become a preferred model of choice in many fields, including neurodevelopmental toxicity studies. This review discusses the benefits of using C. elegans as an alternative to mammalian systems and gives examples of the uses of the nematode in evaluating the effects of major known neurodevelopmental toxins, including manganese, mercury, lead, fluoride, arsenic and organophosphorus pesticides. Reviewed data indicates numerous similarities with mammals in response to these toxins. Thus, C. elegans studies have the potential to predict possible effects of developmental neurotoxicants in higher animals, and may be used to identify new molecular pathways behind neurodevelopmental disruptions, as well as new toxicants.

The effect of dichlorvos on control of drosophila and its safety evaluation under different application methods

Drosophila is a common strawberry pest. In this work, toxicities of the 77.5% EC dichlorvos to 3rd instar larvae and adults of drosophila were evaluated through indoor bioassays and field bioassays, respectively. To insure the safety, dichlorvos dissipation and terminal residue in strawberry by different application methods under field conditions were determined by high-performance liquid chromatography. The decline curves of dichlorvos residues in strawberry corresponded with first-order kinetics, and dichlorvos dissipated rapidly in strawberry with half-life (t_1/2) of 7.58-13.17 h. Terminal residues below the maximum residue limit of strawberry and soil in different distance were achieved after 24 h under different application methods. This article provides guidance to the proper and safe use of dichlorvos in agriculture; it is more reasonable that dichlorvos is applied by embedding on the ground near the strawberry plants covered plastic film with holes.

Effects of gene knockdown of CNP on ventricular remodeling after myocardial ischemia-reperfusion injury through NPRB/Cgmp signaling pathway in rats

This study aimed to explore effects of CNP on ventricular remodeling following myocardial ischemia-reperfusion (I/R) injury through the NPRB/cGMP signaling pathway. Rat cardiomyocytes were assigned into: control, I/R, I/R + CNP, and I/R + 8-Br-cGMP groups. ELISA, qRT-PCR, and Western blotting were used to detect cGMP content and expression, respectively. After model establishment of I/R rats, normal control, CNP^-/- control, I/R, and CNP^-/- groups were set. Indexes of heart were detected using echocardiography and hemodynamics. ELISA was used to measure serum CNP, cGMP, LDH, cTn I, CK-MB, TNF-α, and IL-6 levels. Myocardial infarct was identified by TTC staining, and apoptosis conditions by TUNEL staining. QRT-PCR and Western blotting were adopted to detect expressions of CNP, NPRB, cGMP, and apoptosis-related genes. Compared with control group, cGMP contents and expression in the I/R, I/R + CNP and I/R + 8-Br-cGMP groups were decreased. Levels of LVEDV, LVESV, LVDS, LVDD, IVSD, LVM, LVEDP, and LVSP were higher in the I/R, CNP^-/- control, and CNP^-/- groups than normal control group while LVEF, SV, CO, and ±dp/dtmax were lower. Compared with the normal control group, LDH, cTn I, CK-MB, TNF-α, and IL-6 were higher in the I/R, CNP^-/- control and CNP^-/- groups; pathological changes and myocardial infarction were observed in the I/R, CNP^-/- control, and CNP^-/- groups; expressions of apoptosis-related genes in those groups were higher; while CNP, NPRB, cGMP, and Bcl-2 expressions were decreased. We came to the conclusion that gene knockdown of CNP blocks the NPRB/cGMP signaling pathway, thereby aggravating myocardial I/R injury and causing ventricular remodeling in rats.

Gut Microbiota, Endocrine-Disrupting Chemicals, and the Diabetes Epidemic

Diabetes is rapidly emerging as one of the biggest health concerns worldwide, with profound implications for disability, mortality, and costs. This suddenly escalating rate of diabetes correlates with global industrialization and the production of plastics, pesticides, synthetic fertilizers, electronic waste, and food additives that release endocrine-disrupting chemicals (EDCs) into the environment and the food chain. Emerging evidence indicates an association between exposure of EDCs and diabetes. In humans, these chemicals are also metabolized by the gut microbiota and thereby their toxicodynamics are altered. In this review we highlight studies that focus on the role of gut microbiota in EDC-induced hyperglycemia and dysregulated glucose homeostasis. We also discuss the translational implications of understanding EDC-microbiota interactions for the diagnosis and treatment of diabetes.

Terbufos-sulfone exacerbates cardiac lesions in diabetic rats: a sub-acute toxicity study

Organophosphorus compounds (OPCs) have a wide range of applications, from agriculture to warfare. Exposure to these brings forward a varied kind of health issues globally. Terbufos is one of the leading OPCs used worldwide. The present study investigates the cardiac effect of no observable dose of a metabolite of terbufos, terbufos-sulfone (TS), under non-diabetic and streptozotocin-induced diabetic condition. One hundred nanomoles per rat (1/20 of LD50) was administered intraperitoneally to adult male Wister rats daily for fifteen days. The left ventricle was collected for ultrastructural changes by transmission electron microscopy. The blood samples were collected for biochemical tests including RBC acetylcholinesterase, creatinine kinase (CK), lactate dehydrogenase (LDH), cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides, ALT, AST, and GGT. The study revealed about 10 % inhibition of RBC-AChE in two weeks of TS treatment in non-diabetic rats whereas RBC-AChE activity was significantly decreased in diabetic TS treated rats. CK, LDH, and triglycerides were significantly higher in diabetic TS treated rats. Electron microscopy of the heart showed derangement and lesions of the mitochondria of cardiomyocytes in the TS treated groups. The present study concludes that a non-lethal dose of TS causes cardiac lesions which exacerbate under diabetic condition. Biochemical tests confirmed the ultrastructural changes. It is concluded that a non-lethal dose of TS may be a risk factor for a cardiovascular disease, which may be fatal under diabetic condition.

Gut microbial degradation of organophosphate insecticides-induces glucose intolerance via gluconeogenesis

BACKGROUND

Organophosphates are the most frequently and largely applied insecticide in the world due to their biodegradable nature. Gut microbes were shown to degrade organophosphates and cause intestinal dysfunction. The diabetogenic nature of organophosphates was recently reported but the underlying molecular mechanism is unclear. We aimed to understand the role of gut microbiota in organophosphate-induced hyperglycemia and to unravel the molecular mechanism behind this process.

RESULTS

Here we demonstrate a high prevalence of diabetes among people directly exposed to organophosphates in rural India (n = 3080). Correlation and linear regression analysis reveal a strong association between plasma organophosphate residues and HbA1c but no association with acetylcholine esterase was noticed. Chronic treatment of mice with organophosphate for 180 days confirms the induction of glucose intolerance with no significant change in acetylcholine esterase. Further fecal transplantation and culture transplantation experiments confirm the involvement of gut microbiota in organophosphate-induced glucose intolerance. Intestinal metatranscriptomic and host metabolomic analyses reveal that gut microbial organophosphate degradation produces short chain fatty acids like acetic acid, which induces gluconeogenesis and thereby accounts for glucose intolerance. Plasma organophosphate residues are positively correlated with fecal esterase activity and acetate level of human diabetes.

CONCLUSION

Collectively, our results implicate gluconeogenesis as the key mechanism behind organophosphate-induced hyperglycemia, mediated by the organophosphate-degrading potential of gut microbiota. This study reveals the gut microbiome-mediated diabetogenic nature of organophosphates and hence that the usage of these insecticides should be reconsidered.

The Long-Term Effects of Organophosphates Poisoning as a Risk Factor of CVDs: A Nationwide Population-Based Cohort Study

BACKGROUND

Organophosphorus pesticides are widely used throughout the world. Because of their ease of availability, organophosphorus compounds are commonly used for self-poisoning in developing countries. The acute effects of exposure to organophosphorus pesticides are well known, but the chronic effects are unclear. Recent studies suggest that abnormalities of the central and peripheral nervous systems persisted for up to 5 years after acute poisoning due to a single large dose of organophosphates (OPs). However, the long-term effects on cardiovascular diseases are poorly understood.

METHODOLOGY/PRINCIPAL FINDINGS

An OPs-exposed cohort (N = 7,561) and an age- and gender-matched control cohort (N = 30,244), both identified from the National Health Insurance Research Database, were compared. We utilized the multivariable Cox proportional model to estimate the risks of developing arrhythmia, coronary artery disease (CAD) and congestive heart failure (CHF). The patients with acute poisoning from OPs had higher incidence rates of arrhythmia (5.89 vs. 3.61 per 1,000 person-years), CAD (9.10 vs. 6.88 per 1,000 person-years), and CHF (3.89 vs. 2.98 per 1,000 person-years) compared with that of the non-OPs poisoning cohort, with a crude subhazard ratio (SHR) of 1.40, 1.13, and 1.12, respectively. Additionally, a significantly higher risk of arrhythmia was observed in the OPs poisoning cohort (adjusted SHR = 1.25) compared with the non-OPs poisoning cohort, particularly in male patients (adjusted SHR = 1.33) and those under 49 years of age (adjusted SHR = 3.16). After accounting for the competing risks of death, there was a higher risk of arrhythmia and CAD during a three year follow-up period (adjusted SHR = 1.50 for arrhythmia; adjusted SHR = 1.10 for CAD). We also found an adjusted SHR of 1.36 associated with developing CHF after 6 years of follow-up for OPs poisoning cohort.

CONCLUSIONS

Acute OPs poisoning may continuously impact human health through mechanisms that are unclear. Any supportive measurements that could contribute to a reduction in the risk of heart disease may be beneficial in cases of OPs poisoning survivors.

Identification of naphthol derivatives as novel antifeedants and insecticides. 1

A series of β-naphthol-derived 2-aminobenzothiazolomethylnaphthol derivatives (4a-4q) were synthesized and purified in excellent yields (86-94%) using green protocols and screened for their antifeedant and toxic activities against tobacco caterpillar (Spodoptera litura) and castor semilooper (Achaea janata) using no-choice leaf disk and topical bioassay methods. Four of them, 4d, 4f, 4i, and 4j, were identified to be potent antifeedants with ED50 values of 16.4, 19.3, 7.0, and 5.2 μg/cm(2) against S. litura and 13.9, 17.2, 10.2, and 7.7 μg/cm(2) against A. janata, respectively, and the mortality rate is >95% for 4i and 4j in the case of S. litura and 4j in case of A. janata at a dosage of 0.2 μg/insect. Compounds 4d, 4i, and 4m are moderately toxic to A. janata only. Overall, this study identified a novel class of synthetic compounds that do not belong to organochlorides, organophosphates, carbamates, or neonicotinoids as strong antifeedants as well as insecticides.

Oral exposure to the organophosphorus insecticide, Monocrotophos induces intestinal dysfunction in rats

There is limited experimental evidence to imply the role of organophosphorus insecticides on intestinal dysfunctions. Residues of Monocrotophos (MCP), above maximum residue limits (MRL), have been reported in fruits and vegetables from various parts of India. Hence, in this study, we investigated the potential of MCP to induce intestinal dysfunction in rats. MCP was administered orally to rats at sublethal doses (0.45, 0.9 and 1.8 mg/kgb.w/d) for 30 days. MCP at the highest dose significantly increased the unit weight of the small intestine. MCP increased the activities of intestinal brush border disaccharidases, intestinal alkaline phosphatase, glycyl-glycine dipeptidase, and Na(+)/K(+)-ATPase while it decreased cholesterol: phospholipid ratio. Histology and scanning electron microscopy of small intestine of MCP treated rats revealed disruption in terms of congestion, increased length of villi, goblet cell hyperplasia, infiltration of inflammatory cells and necrotic villi tip. Further, the intestinal transit rate was found to be increased in MCP treated rats. Collectively, our findings provide evidence that repeated oral intake of MCP has the propensity to alter small intestinal structure and functions, which might lead to intestinal dysfunctions and abnormal nutrient uptake and thereby affect the human health. Although we have employed doses, which are higher than those likely to be encountered as residues, we speculate that further studies should be performed to determine whether MCP residues in foods in the long-term will interfere with the digestive capacity of the small intestine and thus exert adverse effects on the health of human.