Pyrethrin and pyrethroid are a relatively new class of pesticides with potent insecticidal properties. Pyrethrins are naturally occurring pesticides obtained from the Chrysanthemum cinerariaefolium flower, while pyrethroids are their synthetic derivatives. They are widely used as the insecticides of choice in agriculture, veterinary medicine, public health programs, and household activities. Pyrethrin, being a broad-spectrum insecticide kills a wide range of pests, while pyrethroids last longer in the environment owing to low susceptibility to sunlight, and greater stability and efficacy than parent molecules. Humans can be exposed through inhalation, ingestion, and dermal routes. Indoor usage of an insecticide poses a serious risk to human health, especially to women, children, and stay-at-home people. Although pyrethrin and pyrethroid are generally considered safe, sustained skin or inhalation exposure or direct contact with open wounds results in higher toxicity to mammals. There is a paucity of data on the impact of pyrethrin and pyrethroid on overall pulmonary health. The respiratory system, from the nose, nasal passages, airways, and bronchi to the pulmonary alveoli, is vulnerable to environmental contaminants such as pesticides because of its anatomical location as well as being a highly blood profused organ. Under and over-functioning of the respiratory system triggers diverse pathologies such as serious infections, allergies, asthma, metastatic malignancies, and auto-immune conditions. While the association between workplace-related pesticide exposures and respiratory diseases and symptoms is well documented, it is important to understand the adverse health impact of pyrethrin and pyrethroid on the general population for awareness and also for better regulation and implementation of the law.

2024-10-01·TOXICOLOGY IN VITRO

Natural pyrethrins induced developmental toxicity of zebrafish swim bladder in vivo and genotoxicity of lung cells in vitro

Article

作者: Li, Ruirui ; Li, Zhong ; Xu, Wenping ; Cheng, Jiagao ; Zhang, Yang ; Tao, Liming ; Zhang, Cheng

Natural pyrethrins (NPs) are insecticidal compounds isolated and extracted from pyrethrum flowers and are primarily use to control sanitary pests. The lungs become the main target after exposure, and its use may pose potential hazards to respiratory health. Therefore, in this paper, the toxic effects of NPs on human lung cells A549 were investigated and the risk of respiratory toxicity of NPs was studied using zebrafish swim bladder as a model. The results showed that NPs induced cytotoxicity, caused oxidative DNA damage and triggered mitochondria-mediated apoptosis. In addition, exposure to NPs decreased zebrafish embryo survival, hatchability, and heartbeat, and may inhibit normal swim bladder development by disrupting Wnt and Hedgehog signaling pathways. In conclusion, our results suggest that NPs can induce cytotoxicity in A549 in vitro and developmental toxicity in zebrafish in vivo. This study provides a conceptual basis for understanding the mechanisms of toxicity of NPs and assessing respiratory health risks in humans.

2024-09-01·PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY

Functional analysis of novel cystatins from Haemaphysalis doenitzi and evaluation of their roles in cypermethrin and λ-cyhalothrin resistance

Article

作者: Lv, Wenxia ; Guo, Feidi ; Zhang, Songbo ; Dong, Kexin ; Yang, Xiaolong ; Wang, Runying ; Gao, Zhihua ; Wang, Yikui ; Liu, Jianing

Currently, the primary strategy for tick control relies on chemical agents. Pyrethrins, which are botanically derived compounds, have demonstrated efficacy in controlling ticks without posing a risk to human or animal health. However, research into pyrethrins' metabolic mechanisms remains sparse. Cystatin, as a reversible binding inhibitor of cysteine protease, may be involved in the initiation of pyrethrin detoxification of Haemaphysalis doenitzi. In this study, two novel cystatins were cloned, HDcyst-3 and HDcyst-4, the relative expression of which was highest in the Malpighian tubules compared with the tick midguts, salivary glands, and ovaries. Prokaryotic expression and in vitro studies revealed that cystatins effectively inhibit the enzymatic activities of cathepsins B and S. RNAi results showed that the reduction of cystatins significantly decreased the engorgement weight, egg mass weight, and egg hatching rate of adult female ticks, and prolonged feeding time by two days. The control rate of rHDcyst-3 and rHDcyst-4 protein vaccination against female adults were 55.9% and 63.2%, respectively. In addition, the tick immersion test showed that cypermethrin and λ-cyhalothrin had significant acaricidal effects against adult unfed H. doenitzi. The qPCR result indicated that compared with the control group, the expression of HDcyst-3 and HDcyst-4 was markedly decreased in the sublethal cypermethrin and λ-cyhalothrin group at LC₅₀. Enzyme activity showed that cypermethrin and λ-cyhalothrin could significantly induce the activities of glutathione S-transferase (GST), carboxylesterase (CarE), and acetylcholinesterase (AchE). The aforementioned results provided indirect evidence that cystatin plays an important role in pyrethrin detoxification and provides a theoretical basis for future acaricide experiments and pest management.

项与 Pyrethrins 相关的新闻（医药）

2022-05-27

·Science Daily

Learning from nature: Biosynthesis of cyanobacterin opens up new class of natural compounds for applications in medicine and agriculture

Researchers have succeeded in understanding the biosynthetic mechanisms for the production of the natural product cyanobacterin, which is produced in small quantities by the cyanobacteria Scytonema hofmanni. In the process, they also discovered a new class of enzymes for building carbon-carbon bonds. The (bio)chemists are thus significantly expanding the biocatalytic repertoire currently known from Nature and are opening up new, sustainable biotechnological applications in medicine and agriculture. Researchers in the groups of Prof. Tobias Gulder from TU Dresden and Prof. Tanja Gulder from Leipzig University have succeeded in understanding the biosynthetic mechanisms for the production of the natural product cyanobacterin, which in Nature is produced in small quantities by the cyanobacteria Scytonema hofmanni. In the process, they also discovered a new class of enzymes for building carbon-carbon bonds. The (bio)chemists are thus significantly expanding the biocatalytic repertoire currently known from Nature and are opening up new, sustainable biotechnological applications in medicine and agriculture. The results of the collaboration have now been published in the journal Nature Chemical Biology. The fact that Nature is an excellent chemist is demonstrated by the abundance of molecules, so-called natural products, which it produces biosynthetically. These natural products are also of central importance to us humans. They are used in many ways in our everyday lives, especially as active agents in medicine and agriculture. Prominent examples are antibiotics such as penicilins isolated from molds, the anti-cancer drug Taxol from the Pacific yew tree, and pyrethrins found in chrysanthemums, which are used to combat pest infestations. The knowledge and understanding of the biosynthetic assembly of such compounds by Nature is essential for the development and production of drugs based on such compounds. In this context, researchers from the groups of Prof. Tobias Gulder (TU Dresden) and Prof. Tanja Gulder (Leipzig University) jointly investigated the biosynthesis of cyanobacterin, which is highly toxic to photosynthetic organisms and is produced in small quantities in Nature by the cyanobacterium Scytonema hofmanni. In their work, the (bio)chemists were not only able to elucidate the biosynthesis of the natural product for the first time, but also discovered a novel enzymatic transformation for the formation of carbon-carbon bonds. This work was made possible by combining modern tools from bioinformatics, synthetic biology, enzymology and (bio)chemical analytics. The focus was on how the central part of the cyanobacterin carbon skeleton is produced. The putative genes for this were first cloned by the method of "Direct Pathway Cloning" (DiPaC) and then activated in the model organism E. coli as a cell factory. DiPaC is a new synthetic biology method previously developed in the laboratory of Tobias Gulder, Professor of Technical Biochemistry at TU Dresden. "DiPaC allows us to transfer entire natural products biosynthetic pathways into recombinant host systems very quickly and efficiently," Tobias Gulder explains. In the next step, the research team analyzed the essential individual steps of cyanobacterin biosynthesis by additionally producing all key enzymes in the host organism E.coli, isolating them and then investigating the function of each enzyme. In the process, they came across a previously unknown class of enzymes called furanolide synthases. These are capable of catalyzing the formation of carbon-carbon bonds following an unusual mechanism. In further studies of these furanolide synthases, these enzymes proved to be efficient in vitro biocatalysts, making them highly attractive for biotechnological applications. "With the furanolide synthases, we have obtained an enzymatic tool that will allow us to develop more environmentally friendly methods for the production of bioactive compounds in the future and thus make significant contributions to a more sustainable chemistry," explains Prof. Tanja Gulder from the Institute of Organic Chemistry at Leipzig University. Next, the two research teams want to specifically search for these novel biocatalysts in other organisms as well, and thus find new bioactive members of this natural products class, as well as develop methods for the biotechnological production and structural diversification of cyanobacterin. "Our work paves the way for the comprehensive development of an exciting class of natural products for applications in medicine and agriculture," the two scientists agree.

100 项与 Pyrethrins 相关的药物交易

登录后查看更多信息