Lambda cyhalothrin

Extensive application of pesticides is usually accompanied with serious problems of pollution
and health hazards. Lambda-cyhalothrin (LCT), a type II synthetic pyrethroid, is widely used
in agriculture, home pest control and protection of foodstuff. This study designed to evaluate
the dose dependent haematological, hepatic and gonadal toxicity of LCT at different dose
levels in Wistar rat. Investigations were also done to find out the toxic effect of lambda cyhalothrin
on lipid metabolism in female rat and its amelioration by taurine. Rats were exposed
to different doses of lambda cyhalothrin over a period of 14 consecutive days. Exposure to
LCT produced ataxia, agitation, rolling and also tremors which were considered as the signs
of toxicity. Significant decrease in erythrocyte count, haemoglobin percentage, seminal fructose
concentration, hepatic and testicular reduced glutathione (GSH) content was observed.
Increase in leukocyte count, serum aspartic and alanine transaminase, hepatic and testicular
malondialdehyde (MDA), testicular and ovarian cholesterol after LCT treatment were seen in
male rats at the dose level of 10.83 mg/kg body wt. (1/7th LD50). Elevated ovarian cholesterol
and MDA and reduced 3β hydroxy steroid dehydrogenase (HSD) and GSH level were also
observed in lambda cyhalothrin exposed female rat at the dose level of 6.29 mg/kg body wt.
(1/9th LD50). LCT caused increase in serum triglyceride, cholesterol, low density lipoproteins
(LDL), very low density lipoproteins (VLDL) and bilirubin and decrease in serum high density
lipoproteins (HDL) in female rat. Taurine pretreatment ameliorated LCT induced altered lipid
metabolic biomarkers in female rat.

Beet armyworm, Spodoptera exigua (Hübner) is an agronomical important and most devastating polyphagous pest that damages a variety of crops around the globe including China. Quercetin is one of the abundant dietary flavonoids and the important defense allelochemicals in plants. Therefore, the changes in insect detoxi-fication enzymes activities in response to plants allelochemicals may result increased the sensitivity to insecticides. In this study, we examined the induced effect of quercetin on larval tolerance to lambda-cyhalothrin in S. exigua. Application of cytochrome P450 inhibitor piperonyl butoxide (PBO) significantly synergized the lambda-cyhalothrin toxicity in quercetin-fed S. exigua larvae. Moreover, larval weight significantly reduced in quercetin, lambda-cyhalothrin, and quercetin + lambda-cyhalothrin treatment. Furthermore, our results showed that the P450 detoxification enzyme effectively increased in all treatments as compared to the control. Quantitative Real-time PCR analysis revealed that expression level of CYP6AE10 significantly upreg-ulated in larvae treated with quercetin, lambda-cyhalothrin and quercetin + lambda-cyhalothrin in the midgut and fat body respectively. In addition, RNAi mediated knockdown of CYP6AE10 in S. exigua larvae significantly decreased the transcription level of target cytochrome P450 gene followed by the exposure with quercetin, lambda-cyhalothrin, and quercetin + lambda-cyhalothrin. Similarly, the knockdown of CYP6AE10 by the injection of dsRNA led to increased mortality after the treatment with respective chemicals. Overall, these data showed that P450s might possibly play an important role in the metabolic adaptation of S. exigua larvae to its host plant defense allelochemicals as well as insecticides. In conclusion, S. exigua can take benefit from its host plant's secondary metabolites to elaborate its defense against synthetic insecticides.

Pesticides were introduced some decades ago with the aim of enhancing crop yield by protecting crops from pests. Due to adaptations and resistance that has been developed by pests against these chemicals, higher amounts and new chemical compounds are used to protect crops; this ultimately leads to undesired side effects in the crops. The aim of this study was to investigate the effect of acetamiprid and lambda-cyhalothrin application on reducing sugar, total protein, ascorbic acid, total phenolics and chlorophyll content in onion and tomato. This study was conducted by applying different concentrations (recommended, under-dose and over-dose) of these pesticides to onion and tomato and measuring the content of the aforementioned biochemical parameters after harvest using spectrophotometric methods. It was observed that both acetamiprid and lambda-cyhalotrhin application caused decreases in the reducing sugar content of onion and tomato. Similar trend was observed for ascorbic acid and chlorophyll content, except acetamiprid treated onion which recorded higher ascorbic acid content as compared to the control. Lambda-cyhalothrin and acetamiprid application caused increases in the total protein content of all the treated onion and tomato samples as compared to their controls. All the acetamiprid and lambda-cyhalothrin treated onions and tomatoes recorded lower total phenolic contents as compared to their respective controls. Most of the effects of acetamiprid and lambda-cyhalothrin on the parameters studied were observed in the recommended and/or the over-dose treated samples. Vegetable growers should be educated on the correct application of pesticides so that the nutrients in vegetables will be safeguarded and retained.

Background
Lambda-cyhalothrin (LCT) is an isomeric form of the two biologically active diastereoisomeric pairs of cyhalothrin, containing an alpha-cyano group. Taurine or 2-aminoethane sulfonic acid is a sulfur-containing α-amino acid that is the most abundant free amino acid in most mammal tissue.
Aim and Objectives
The present study was focused to investigate lambda-cyhalothrin induced nephrotoxicity and renal oxidative stress as well as to evaluate the alleviating role of taurine in this condition.
Methods
Lambda-cyhalothrin was administered orally at two dose levels (10.83 and 15.17 mg/kg body weight) alone or in combination after pre-treatment of taurine (50 mg/kg body weight) for consecutive 14 days.
Results
Renal toxicity was measured by a significant decrease in renal index, reduction in kidney protein and an increase in serum protein in lambda-cyhalothrin intoxicated rats. At the same time, lambda-cyhalothrin induced a significant renal oxidative stress demonstrated by elevated renal malondialdehyde content and oxidized glutathione level accompanied by a reduction in reduced glutathione and antioxidant enzymes in rats. Lambda-cyhalothrin induced renal toxicity and oxidative stress in the rat was significantly ameliorated due to the administration of taurine as an antidote.
Conclusion
All of these findings of the present study strongly suggest the protective role of taurine in the pathophysiology of lambda-cyhalothrin-induced renal toxicity and oxidative stress.

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