The development of effective and safe repellents against arthropods is very important, because there are no effective vaccines against arthropod-borne viruses (arboviruses) and parasites. Arboviruses and parasites are transmitted to humans from arthropods, and mosquitoes are the most common arthropods associated with dengue, malaria, and yellow fever. Enormous efforts have been made to develop effective repellents against arthropods, and thus far synthetic repellents have been widely used. However, the use of synthetic repellents has raised several concerns in terms of environmental and human health risks and safety. Thus, plant essential oils (EOs) have been widely used as an alternative to synthetic repellents. In this review, we briefly introduce and summarize recent studies that have investigated EOs as insect repellents. Current technology and research trends to develop effective and safe repellents from plant EOs are also described in this review.

In this study, we investigated the anti-microbial, anti-inflammatory, and anti-lipogenic effects of hemp (Cannabis sativa L.) seed hexane extracts, focusing on the Propionibacterium acnes-triggered inflammation and lipogenesis. Hemp seed hexane extracts (HSHE) showed anti-microbial activity against P. acnes. The expression of iNOS, COX-2, and the subsequent production of nitric oxide and prostaglandin increased after infection of P. acnes in HaCaT cells, however, upon treating with HSHE, their expressions were reduced. P. acnes-induced expressions of IL-1β and IL-8 were also reduced. HSHE exerted anti-inflammatory effects by regulating NF-κB and MAPKs signaling and blunting the translocation of p-NF-κB to the nucleus in P. acnes-stimulated HaCaT cells. Moreover, P. acnes-induced phosphorylation of ERK and JNK, and their downstream targets c-Fos and c-Jun, was also inhibited by HSHE. In addition, the transactivation of AP-1 induced by P. acnes infection was also downregulated by HSHE. Notably, HSHE regulated inflammation and lipid biosynthesis via regulating AMPK and AKT/FoxO1 signaling in IGF-1-induced inflammation and lipogenesis of sebocytes. In addition, HSHE inhibited 5-lipoxygenase level and P. acnes-induced MMP-9 activity, and promoted collagen biosynthesis in vitro. Thus, HSHE could be utilized to treat acne vulgaris, through its anti-microbial, anti-inflammatory, anti-lipogenic, and collagen-promoting properties.

Cigarette smoke contains more than 4,500 chemicals; most of which are highly reactive free radicals, which induce proinflammatory and carcinogenic reactions. Numerous efforts have focused extensively on the role of cigarette smoking as a cause of many diseases. Extracellular vesicles and exosomes have recently received increasing interest for their diagnostic and therapeutic roles in many diseases. However, research done on the role of extracellular vesicles and exosomes on cigarette smoke‐induced chronic disease is still in its infancy. In this review, we summarize the recently addressed roles of extracellular vesicles and exosomes in the pathogenesis of cigarette smoke‐related diseases, such as chronic obstructive pulmonary disease, cardiovascular disease, lung cancer, and oral cancer. Moreover, their potential utilization and future prospects as diagnostic biomarkers for cigarette smoke‐related diseases are described.