Protective effect of α-lipoic acid against α-cypermethrin-induced changes in rat cerebellum

Pyrethroids toxicity in vertebrates and invertebrates and amelioration by bioactive compounds: A review

Generations of different synthetic pesticides have been launched over time to maintain balance between production and consumption of the agricultural yield, control various disease programmes, store grains, etc. Pyrethroids, which are supposed to be non-toxic, have been excessively implemented and have contaminated soil and water bodies. Thus, pyrethroids cause severe and dreadful pernicious effects on various life forms residing in soil, air, and water. Various obnoxious effects of pyrethroids have been analyzed in the vertebrate and invertebrate systems of the animal kingdom. Pyrethroids, namely, Cypermethrin, Deltamethrin, Beta-cyfluthrin, Esfenvalerate, Fenvalerate, and Bifenthrin, have set out various types of degenerative and toxic impacts that include oxidative stress, hepatotoxicity, immunotoxicity involving thymic and splenic toxicity, neurotoxicity, nephrotoxicity, foetal toxicity, alterations in serum calcium and phosphate levels, cerebral and bone marrow degeneration, degeneration of the reproductive system, histological alteration, and DNA damage. Bioactive compounds like Diosmin, Curcumin, Rutin, Spirulina platensis, sesame oil, Naringin, Allicin, Piperine, alpha-lipoic acid, alpha-tocopherol, Cyperus rotundus L. tuber extract, herbal syrup from chicory and artichoke leaves, green tea extract, Quercetin, Trans-ferulic acid, Ascorbic acid, Propolis, ethanolic extract of grape pomace, and Melatonin have been reported to sublime the toxic effects of these pesticides. The expanding harmfulness of pesticides is a real and demanding issue that needs to be overcome, and bioactive compounds have been shown to reduce the toxicity in vivo as well as in vitro.

Hepatoprotective and Antioxidant Effects of Nanopiperine against Cypermethrin via Mitigation of Oxidative Stress, Inflammations and Gene Expression Using qRT-PCR

Cypermethrin (Cyp) is a pyrethroid that has been associated with the toxicity of various organs. The aim of our study was to evaluate the hepatoprotective and antioxidant activities of nano-piperine (NP) against Cyp toxicity. Cyp (50 mg/kg) was administered orally in all animals of groups III-VI for 15 days. Groups IV-VI each received three doses of NP (125, 250, and 500 µg/kg/day) for 10 days after receiving the Cyp dosage, which was given after 1 h. A rise in serum biomarkers (ALT, AST, ALP, total protein, and albumin), which are indicators of toxicity alongside anomalous oxidative stress indices (lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD) and catalase), was detected. After Cyp treatment, we observed upregulated cytokines, caspase expression, and histological analysis that the showed distortion of cell shape. However, the administration of NP dramatically reversed all of the Cyp-induced alterations, inducing reductions in serum marker levels, stress level, the production of cytokines, and caspase expression. Additionally, all of the histopathological alterations were minimized to values that were comparable to normal levels. The present findings suggested that NP exhibits potent antioxidant and anti-inflammatory activities that can protect rats' livers against Cyp-induced liver damage through hepatoprotective activities.

Remyelinating activities of Carvedilol or alpha lipoic acid in the Cuprizone-Induced rat model of demyelination

Multiple sclerosis (MS) is a complex and multifactorial neurodegenerative disease with unknown etiology, MS is featured by multifocal demyelinated lesions distributed throughout the brain. It is assumed to result from an interaction between genetic and environmental factors, including nutrition. Therefore, different therapeutic approaches are aiming to stimulate remyelination which could be defined as an endogenous regeneration and repair of myelin in the central nervous system. Carvedilol is an adrenergic receptor antagonist. Alpha lipoic acid (ALA) is a well-known antioxidant. Herein, we investigated the remyelination potential of Carvedilol or ALA post-Cuprizone (CPZ) intoxication. Carvedilol or ALA (20 mg/kg/d) was administrated orally for two weeks at the end of the five weeks of CPZ (0.6%) administration. CPZ provoked demyelination, enhanced oxidative stress, and stimulated neuroinflammation. Histological investigation of CPZ-induced brains showed obvious demyelination in the corpus callosum (CC). Both Carvedilol and ALA demonstrated remyelinating activities, with corresponding upregulation of the expression of MBP and PLP, the major myelin proteins, downregulation of the expression of TNF-α and MMP-9, and decrement of serum IFN-γ levels. Moreover, both Carvedilol and ALA alleviated oxidative stress, and ameliorated muscle fatigue. This study highlights the neurotherapeutic potential of Carvedilol or ALA in CPZ-induced demyelination, and offers a better model for the exploring of neuroregenerative strategies. The current study is the first to demonstrate a pro-remyelinating activity for Carvedilol, as compared to ALA, which might represent a potential additive benefit in halting demyelination and alleviating neurotoxicity. However, we could declare that Carvedilol showed a lower neuroprotective potential than ALA.

Effects of pyrethroids on the cerebellum and related mechanisms: a narrative review

Pyrethroids (PYRs) are a group of synthetic organic chemicals that mimic natural pyrethrins. Due to their low toxicity and persistence in mammals, they are widely used today. PYRs exhibit higher lipophilicity than other insecticides, which allows them to easily penetrate the blood-brain barrier and directly induce toxic effects on the central nervous system. Several studies have shown that the cerebellum appears to be one of the regions with the largest changes in biomarkers. The cerebellum, which is extremely responsive to PYRs, functions as a crucial region for storing motor learning memories. Exposure to low doses of various types of PYRs during rat development resulted in diverse long-term effects on motor activity and coordination functions. Reduced motor activity may result from developmental exposure to PYRs in rats, as indicated by delayed cerebellar morphogenesis and maturation. PYRs also caused adverse histopathological and biochemical changes in the cerebellum of mothers and their offspring. By some studies, PYRs may affect granule cells and Purkinje cells, causing damage to cerebellar structures. Destruction of cerebellar structures and morphological defects in Purkinje cells are known to be directly related to functional impairment of motor coordination. Although numerous data support that PYRs cause damage to cerebellar structures, function and development, the mechanisms are not completely understood and require further in-depth studies. This paper reviews the available evidence on the relationship between the use of PYRs and cerebellar damage and discusses the mechanisms of PYRs.

Neuroprotective Effects of Nano-Curcumin against Cypermethrin Associated Oxidative Stress and Up-Regulation of Apoptotic and Inflammatory Gene Expression in Rat Brains

Cypermethrin (CPM) is the most toxic synthetic pyrethroid that has established neurotoxicity through oxidative stress and neurochemical agitation in experimental rats. The toxic effects are supposed to be mediated by modifying the sodium channels, reducing Na-K ATPase, acetylcholine esterase (AchE), and monoamine oxidase (MAO). The use of curcumin nanoparticles (NC) that have potent antioxidant, anti-inflammatory and antiapoptotic properties with improved bioavailability attenuates neurotoxicity in rat brains. To test this hypothesis, animals were divided into five groups, each having six animals. Group-I control received vehicle only, while Group-II was treated with 50 mg/kg CPM. Group-III and Group-IV received both CPM and NC 2.5 mg/kg and 5 mg/kg, respectively. Group-V received 5 mg of NC alone. The CPM and NC were given by oral route. Afterwards, brain antioxidant status was measured by assessing lipid peroxidation (LPO), 4-HNE, glutathione reduced (GSH), antioxidant enzyme catalase, and superoxide dismutase (SOD) along with neurotoxicity markers Na-K ATPase, AchE, and MAO. Inflammation and apoptosis indices were estimated by ELISA, qRT-PCR, and immunohistochemistry, while morphologic changes were examined by histopathology. Observations from the study confirmed CPM-induced neurotoxicity by altering Na-K ATPase, AchE, and MAO, and by decreasing the activity of antioxidant enzymes and GSH. Oxidative stress marker LPO and the level of inflammatory interleukins IL-6, IL-1β, and TNF-α were notably high, and elevated expressions of Bax, NF-kB, and caspase-3 and -9 were reported in CPM group. However, NC treatment against CPM offers protection by improving antioxidant status and lowering LPO, inflammation, and apoptosis. The neurotoxicity marker’s enzyme successfully attenuated after NC treatment. Therefore, this study supports the administration of NC effectively ameliorated CPM-induced neurotoxicity in experimental rats.

Evaluation of protective effects of quercetin against cypermethrin-induced lung toxicity in rats via oxidative stress, inflammation, apoptosis, autophagy, and endoplasmic reticulum stress pathway

Cypermethrin (CYP), a type II synthetic pyrethroid, is the most widely used insecticide worldwide. Inhalation of it may cause side effects. This study is aimed to examine potential protection of quercetin (QUE) which is a well-known antioxidant in CYP-induced lung toxicity. Accordingly, 35 Spraque Dawley male rats were divided into five equal groups as follows: I-Control group, II-QUE group (50 mg/kg/b.w. QUE), III-CYP group (25 mg/kg/b.w. CYP), IV-CYP + QUE 25 (25 mg/kg/b.w. CYP + 25 mg/kg/b.w. QUE), V-CYP + QUE (25 mg/kg/b.w. CYP + 50 mg/kg/b.w. QUE) were treated with oral gavage throughout 28 days. CYP intoxication was associated with increased malondialdehyde level while glutathione concentration, activities of glutathione peroxidase, superoxide dismutase, and catalase reduced. CYP adminisitration caused of apoptosis in the lung by up-regulating caspase-3 and Bax levels and down-regulating Bcl-2. CYP also caused of endoplasmic reticulum (ER) stress by increasing mRNA transcript levels of PERK, IRE1, ATF6, and GRP78. Additionally, it was observed that CYP administration activated IL-6/JAK2/STAT3/MAPK14 signaling pathway and levels of IL-1β, NF-κB, TNF-α, and iNOS in the lung tissue. Therefore, it was determined that CYP administration triggered autophagy by upregulating LC3A and LC3B mRNA transcript levels. Moreover, the protein levels of NF-κB, caspase-3, Bax, Bcl-2, and cytochorme-c were examined by Western blot analysis. However, co-treatment with QUE at a dose of 25 and 50 mg/kg considerably protective oxidative stress, inflammation, apoptosis, ER stress, autophagy, and IL-6/JAK2/STAT3/MAPK14 signaling pathway in lung tissue. Overall, the findings of this study suggest that lung damage associated with CYP toxicity could be protected by QUE administration.

The protective role of alpha-lipoic acid on the appearance of fibronectin and laminin in renal tubules following diazinon exposure: An experimental immunohistochemical study

Extracellular matrix (ECM) exerts a major role in maintaining the structure and developmental processes of tissues. To form the tubular basement membrane in the kidney, sulfate proteoglycans, collagen, laminin, fibronectin, and other glycoproteins congregate in the ECM. As an insecticide, diazinon (DZN) may alter the proportion of ECM by cholinesterase activity inhibition and oxidative stress. The naturally, alpha-lipoic acid (ALA) plays an effective and therapeutic role in the treatment of toxicities and diseases in the body. In the current study, an attempt was made to evaluate the impacts of alpha-lipoic acid on the distribution of fibronectin and laminin in the renal tubules of male Wistar rats following exposure to diazinon. In this study, the animal groups comprised 30 adult male Wistar rats (almost three months old) randomly distributed into the following groups; control, DZN (40 mg/kg), DZN + ALA (40 mg/kg+100 mg/kg), ALA (100 mg/kg), and sham. The rats were anesthetized after six weeks. Blood sampling was performed, and kidneys were removed for immunohistochemistry study. Diazinon reduced the distribution of fibronectin and laminin and significantly inhibited cholinesterase activity in the renal tubules. Furthermore, urea and creatinine levels were higher in diazinon than in other groups. ALA in the co-treatment group enhanced cholinesterase activity and distribution of both glycoproteins in the renal tubules. Urea and creatinine levels were meaningfully diminished in the DZN + ALA group. The nephrotoxic effect of diazinon in vivo was the reduced distribution of laminin and fibronectin, probably induced by cholinesterase activity inhibition. As an antioxidant with specific properties, ALA reduces the nephrotoxic effects of diazinon by multifarious mechanisms.

Predominant role of antioxidants in ameliorating the oxidative stress induced by pesticides

Oxidative stress has been reported as one of the adverse effects caused due to pesticides, which is the main mechanism of the toxicity in humans and animals and is a useful parameter in monitoring studies. It involves an imbalance in the equilibrium state of ROS and antioxidant defenses leading to alterations in various antioxidant enzyme levels and lipid peroxidation. The objective of the current paper is to present a review of the potential role and protective mechanism action of the antioxidant micronutrient supplementation to ameliorate the oxidative stress induced by pesticides. Studies in animal models and human were retrieved through the relevant search of the literature and categorized. Various animal studies were categorized according to the type of supplementation. Animal studies provide evidence to conclude the potential protective role of antioxidants in ameliorating the adverse effects of pesticides. Similar studies in humans are meager suggesting for further comprehensive research.