The impact of age-related sub-chronic exposure to chlorpyrifos on metabolic indexes in male rats

The association of isocarbophos and isofenphos with different types of glucose metabolism: The role of inflammatory cells

To investigate the associations between isocarbophos and isofenphos with impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2DM), and to assess the mediation roles of inflammation cells. There were 2701 participants in the case-control study, including 896 patients with T2DM, 900 patients with IFG, 905 subjects with NGT. Plasma isocarbophos and isofenphos concentrations were measured using gas chromatography and triple quadrupole tandem mass spectrometry. Generalized linear models were used to calculate the relationships between plasma isofenphos and isocarbophos levels with inflammatory factor levels and T2DM. Inflammatory cell was used as mediators to estimate the mediating effects on the above associations. Isocarbophos and isofenphos were positively related with T2DM after adjusting for other factors. The odds ratio (95% confidence interval) (OR (95%CI)) for T2DM was 1.041 (1.015, 1.068) and for IFG was 1.066 (1.009, 1.127) per unit rise in ln-isocarbophos. The prevalence of T2DM increased by 6.4% for every 1 unit more of ln-isofenphos (OR (95% CI): 1.064 (1.041, 1.087)). Additionally, a 100% rise in ln-isocarbophos was linked to 3.3% higher ln-HOMA2IR and a 0.029 mmol/L higher glycosylated hemoglobin (HbA1c) (95% CI: 0.007, 0.051). While a 100% rise in ln-isofenphos was linked to increase in ln-HOMA2 and ln-HOMA2IR of 5.8% and 3.4%, respectively. Furthermore, white blood cell (WBC) and neutrophilic (NE) were found to be mediators in the relationship between isocarbophos and T2DM, and the corresponding proportions were 17.12% and 17.67%, respectively. Isofenphos and isocarbophos are associated with IFG and T2DM in the rural Chinese population, WBC and NE have a significant role in this relationship.

Metformin ameliorates cardiopulmonary toxicity induced by chlorpyrifos

Chlorpyrifos (CPF) is a widely used pesticide that can impair body organs. Nonetheless, metformin is known for its protective role against dysfunction at cellular and molecular levels led by inflammatory and oxidative stress. This study aimed to investigate the modulatory impacts of metformin on CPF-induced heart and lung damage. Following the treatment of Wistar rats with different combinations of metformin and CPF, plasma, as well as heart and lung tissues, were isolated to examine the level of oxidative stress biomarkers like reactive oxygen species (ROS) and malondialdehyde (MDA), inflammatory cytokines such as tumor necrosis alpha (TNF-α), high mobility group box 1 (HMGB1) gene, deoxyribonucleic acid (DNA) damage, lactate, ADP/ATP ratio, expression of relevant genes (TRADD, TERT, KL), and along with histological analysis. Based on the findings, metformin significantly modulates the impairments in heart and lung tissues induced by CPF.

Obesity II: Establishing causal links between chemical exposures and obesity

Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.

A systematic review on the metabolic effects of chlorpyrifos

Organophosphate (OP) pesticides, including chlorpyrifos (CPF), can alter metabolic hemostasis. The current systematic study investigated blood glucose, lipid profiles, and body weight alterations in rodents and fish exposed to CPF. The systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Guidelines, querying online databases, including Web of Science, PubMed, and Scopus and also search engine including Google Scholar, through January 2021. Studies on rodent and fish exposed to CPF assessing metabolic functions were selected. All studies were in the English language, with other languages being excluded from the review. Two investigators independently assessed each of the articles. The first author's name, publication date, animal model, age, sample size, gender, dose, duration, and route of exposure and outcomes were extracted from each publication. The present review summarizes findings from 61 publications on glycemic, lipid profile, insulin, and body weight changes in rodents and fish exposed to CPF exposure. Most of the studies reported hyperglycemia, hyperlipidemia, and decreased insulin levels and body weight following exposure to CPF. Additionally, we confirmed that the CPF-induced metabolic alterations were both dose- and time-dependent. Our findings support an association between CPF exposure and metabolic diseases. However, more studies are needed to identify the metabolic-disrupting effects of CPF and their underlying mechanisms.

Pinocembrin pretreatment counteracts the chlorpyrifos-induced HO-1 downregulation, mitochondrial dysfunction, and inflammation in the SH-SY5Y cells

Chlorpyrifos (CPF), an insecticide, induces pro-oxidant, pro-inflammatory, and pro-apoptotic effects in animal cells. Contamination with CPF occurs not only in farms, since CPF is found in the food consumed in homes. Recently, it was demonstrated that CPF affects the mitochondria, inhibiting components of the electron transfer chain (ETC), causing loss of mitochondrial membrane potential (MMP), and reducing the synthesis of adenosine triphosphate (ATP) by the Complex V. Pinocembrin (PB) is found in propolis and exhibits antioxidant, anti-inflammatory, and anti-apoptotic effects in mammalian cells. PB is a potent inducer of the nuclear factor erythroid 2-related factor 2 (Nrf2), which is a major transcription factor controlling the expression of heme oxygease-1 (HO-1), among others. In the present work, we investigated whether PB would be able to prevent the mitochondrial and immune dysfunctions in the human neuroblastoma SH-SY5Y cells exposed to CPF. PB was tested at 1-25 µM for 4 h before the administration of CPF at 100 µM for additional 24 h. We found that PB prevented the CPF-induced inhibition of ETC, loss of MMP, and decline in the ATP synthesis. PB also promoted anti-inflammatory actions in this experimental model. Silencing of Nrf2 or inhibition of HO-1 suppressed the PB-induced effects in the CPF-challenged cells. Thus, PB promoted beneficial effects by a mechanism dependent on the Nrf2/HO-1/CO + BR axis in the CPF-treated cells.

Chronic oral exposure to pesticides and their consequences on metabolic regulation: role of the microbiota

Pesticides have long been used in agriculture and household treatments. Pesticide residues can be found in biological samples for both the agriculture workers through direct exposure but also to the general population by indirect exposure. There is also evidence of pesticide contamination in utero and trans-generational impacts. Whilst acute exposure to pesticides has long been associated with endocrine perturbations, chronic exposure with low doses also increases the prevalence of metabolic disorders such as obesity or type 2 diabetes. Dysmetabolism is a low-grade inflammation disorder and as such the microbiota plays a role in its etiology. It is therefore important to fully understand the role of microbiota on the genesis of subsequent health effects. The digestive tract and mostly microbiota are the first organs of contact after oral exposure. The objective of this review is thus to better understand mechanisms that link pesticide exposure, dysmetabolism and microbiota. One of the key outcomes on the microbiota is the reduced Bacteroidetes and increased Firmicutes phyla, reflecting both pesticide exposure and risk factors of dysmetabolism. Other bacterial genders and metabolic activities are also involved. As for most pathologies impacting microbiota (including inflammatory disorders), the role of prebiotics can be suggested as a prevention strategy and some preliminary evidence reinforces this axis.

Impact of pesticide exposure on adipose tissue development and function

Obesity is a leading cause of morbidity, mortality and health care expenditure whose incidence is rapidly rising across the globe. Although the cause of the obesity epidemic is typically viewed as a product of an increased availability of high calorie foods and/or a reduction in physical activity, there is mounting evidence that exposure to synthetic chemicals in our environment may play an important role. Pesticides, are a class of chemicals whose widespread use has coincided with the global rise of obesity over the past two decades. Importantly, given their lipophilic nature many pesticides have been shown to accumulate with adipose tissue depots, suggesting they may be disrupting the function of white adipose tissue (WAT), brown adipose tissue (BAT) and beige adipose tissue to promote obesity and metabolic diseases such as type 2 diabetes. In this review, we discuss epidemiological evidence linking pesticide exposure with body mass index (BMI) and the incidence of diabetes. We then review preclinical studies in rodent models which have directly evaluated the effects of different classes of insecticides and herbicides on obesity and metabolic dysfunction. Lastly, we review studies conducted in adipose tissue cells lines and the purported mechanisms by which pesticides may induce alterations in adipose tissue function. The review of the literature reveals major gaps in our knowledge regarding human exposure to pesticides and our understanding of whether physiologically relevant concentrations promote obesity and elicit alterations in key signaling pathways vital for maintaining adipose tissue metabolism.