Synthesis and biological evaluation of folic acid-rotenol conjugate as a potent targeted anticancer prodrug.

Rotenone, a plant-based agricultural insecticide, has been shown to have anti-tumor activity through targeting mitochondrial complex I in cancer cells. However, off-target toxic side effect on nervous systems have greatly restricted the application of rotenone as anticancer drugs. Here, a folic acid-rotenol (FA-rotenol) conjugate was prepared by covalent coupling of the tumor-targeting ligand folic acid with rotenone derivative-rotenol to enhance its accumulation at tumor site. FA-rotenol conjugates present high in vitro cytotoxicties against several cell lines by inducing mitochondrial membrane potential depolarization and increasing the level of intracellular reactive oxygen species (ROS) to activate the mitochondrial pathway of apoptosis and enhance the G2/M cell cycle arrest. Because of the high affinity with over-expressed folate receptors, FA-rotenol conjugate demonstrated more effective in vivo therapeutic outcomes in 4T1 tumor-bearing mice than rotenone and rotenol. In addition, FA-rotenol conjugate can markedly inhibit the cell migration and invasion of HepG-2 cells. These studies confirm the feasibility of tumor-targeted ligand conjugated rotenone derivatives for targeted antitumor therapy; likewise, they lay the foundations for the development of other rotenol-conjugates with antitumor potential.

Role of Histamine H3 Receptor Antagonist Pitolisant in Early Neural Differentiation of Mouse Embryonic Stem Cells.

The histamine H3 receptor, prominently expressed in neurons with a minor presence in glial cells, acts as both an autoreceptor and an alloreceptor, controlling the release of histamine and other neurotransmitters. The receptor impacts various essential physiological processes. Our team's initial investigations had demonstrated that the histamine H3 receptor antagonists could facilitate nerve regeneration by promoting the histamine H1 receptors on primary neural stem cells (NSCs) in the traumatic brain injury mouse, which suggested the potential of histamine H3 receptor as a promising target for treating neurological disorders and promoting nerve regeneration. Pitolisant (PITO) is the only histamine H3 receptor antagonist approved by the Food and Drug Administration (FDA) for treating narcolepsy. However, there is no report on Pitolisant in neural development or regeneration, and it is urgent to be further studied in strong biological activity models in vitro. The embryonic stem (ES) cells were differentiated into neural cells in vitro, which replicated the neurodevelopmental processes that occur in vivo. It also provided an alternative model for studying neurodevelopmental processes and testing drugs for neurological conditions. Therefore, we aimed to elucidate the regulatory role of Pitolisant in the early differentiation of ES cells into neural cells. Our results demonstrated that Pitolisant could promote the differentiation of ES cells toward NSCs and stimulated the formation of growth cones. Furthermore, Pitolisant was capable of inducing the polarization of NSCs through the cAMP-LKB1-SAD/MARK2 pathway, but had no significant effect on later neuronal maturation. Pitolisant altered mitochondrial morphology and upregulated the levels of mitochondrion-related proteins TOM20, Drp1, and p-Drp1, and reversed the inhibitory effect of Mdivi-1 on mitochondrial fission during the early neural differentiation of ES cells. In addition, Pitolisant induced the increase in cytosolic Ca2+. Our study provided an experimental foundation for the potential application of histamine H3 receptor-targeted modulators in the field of neuroregeneration.

IMF-PR: An Improved Morton-Filter-Based Pseudonym-Revocation Scheme in VANETs.

Vehicle ad hoc networks (VANETs) are special wireless networks which help vehicles to obtain continuous and stable communication. Pseudonym revocation, as a vital security mechanism, is able to protect legal vehicles in VANETs. However, existing pseudonym-revocation schemes suffer from the issues of low certificate revocation list (CRL) generation and update efficiency, along with high CRL storage and transmission costs. In order to solve the above issues, this paper proposes an improved Morton-filter-based pseudonym-revocation scheme for VANETs (IMF-PR). IMF-PR establishes a new distributed CRL management mechanism to maintain a low CRL distribution transmission delay. In addition, IMF-PR improves the Morton filter to optimize the CRL management mechanism so as to improve CRL generation and update efficiency and reduce the CRL storage overhead. Moreover, CRLs in IMF-PR store illegal vehicle information based on an improved Morton filter data structure to improve the compress ratio and the query efficiency. Performance analysis and simulation experiments showed that IMF-PR can effectively reduce storage by increasing the compression gain and reducing transmission delay. In addition, IMF-PR can also greatly improve the lookup and update throughput on CRLs.

PCP: A Pseudonym Change Scheme for Location Privacy Preserving in VANETs.

In vehicular ad hoc networks (VANETs), pseudonym change is considered as the vital mechanism to support vehicles' anonymity. Due to the complicated road conditions and network environment, it is a challenge to design an efficient and adaptive pseudonym change protocol. In this paper, a pseudonym change protocol for location privacy preserving (PCP) is proposed. We first present the requirements of pseudonym change in different scenarios. According to variable network states and road conditions, vehicles are able to take different pseudonym change strategies to resist the tracking by global passive adversaries. Furthermore, the registration protocol, authentication protocol, pseudonym issuance protocol, and pseudonym revocation protocol are introduced for the pseudonym management mechanism. As a consequence, it is not feasible for global passive adversaries to track a vehicle for a long time and obtain the trajectory of the vehicle. The analysis results show that the security and performance of PCP are improved compared with the traditional ones.

Inhibition of MyD88 by LM8 Attenuates Obesity-Induced Cardiac Injury.

Obesity-induced cardiomyopathy involves chronic and sustained inflammation. The toll-like receptor 4 (TLR4) signaling pathway can associate innate immunity with obesity. Myeloid differentiation primary response 88 (MyD88), an indispensable downstream adaptor molecule of TLR4, has been reported to mediate obesity complications. However, whether inhibition of MyD88 can mitigate obesity-induced heart injury remains unclear. LM8, a new MyD88 inhibitor, exhibits prominent anti-inflammatory activity in lipopolysaccharide-treated macrophages. In this study, the protective effects of LM8 on a high-fat diet (HFD)-induced heart injury were assessed in a mouse model of obesity. As suggested from the achieved results, LM8 treatment alleviated HFD-induced pathological and functional damages of the heart in mice. Meantime, the treatment of mice with LM8 could significantly inhibit myocardial hypertrophy, fibrosis, inflammatory cytokines expression, and inflammatory cell infiltration induced by HFD. Besides, LM8 administration inhibited the formation of MyD88/TLR4 complex, phosphorylation of ERK, and activation of nuclear factor-κB induced by HFD. According to the achieved results, MyD88 inhibitor LM8 ameliorated obesity-induced heart injury by inhibiting MyD88-ERK/nuclear factor-κB dependent cardiac inflammatory pathways. Furthermore, targeting MyD88 might be a candidate of a therapeutic method to treat obesity-induced heart injury.

iTRAQ-Based Quantitative Proteomic Analysis of the Arabidopsis Mutant opr3-1 in Response to Exogenous MeJA.

Jasmonates (JAs) regulate the defense of biotic and abiotic stresses, growth, development, and many other important biological processes in plants. The comprehensive proteomic profiling of plants under JAs treatment provides insights into the regulation mechanism of JAs. Isobaric tags for relative and absolute quantification (iTRAQ)-based quantitative proteomic analysis was performed on the Arabidopsis wild type (Ws) and JA synthesis deficiency mutant opr3-1. The effects of exogenous MeJA treatment on the proteome of opr3-1, which lacks endogenous JAs, were investigated. A total of 3683 proteins were identified and 126 proteins were differentially regulated between different genotypes and treatment groups. The functional classification of these differentially regulated proteins showed that they were involved in metabolic processes, responses to abiotic stress or biotic stress, the defense against pathogens and wounds, photosynthesis, protein synthesis, and developmental processes. Exogenous MeJA treatment induced the up-regulation of a large number of defense-related proteins and photosynthesis-related proteins, it also induced the down-regulation of many ribosomal proteins in opr3-1. These results were further verified by a quantitative real-time PCR (qRT-PCR) analysis of 15 selected genes. Our research provides the basis for further understanding the molecular mechanism of JAs' regulation of plant defense, photosynthesis, protein synthesis, and development.

L6H9 attenuates LPS-induced acute lung injury in rats through targeting MD2.

Acute lung injury (ALI) is a clinical syndrome characterized by respiratory failure and acute inflammatory response. Myeloid differentiation protein 2 (MD2) has been reported to play a pivotal role in the recognition of LPS and LPS-mediates inflammatory response. There have been no clinically effective therapeutic drugs for ALI. L6H9, an inhibitor of MD2, showed anti-inflammatory effects and cardiac protective activity. However, its effect on ALI has not been elucidated. In this study, intratracheal instillation of LPS was employed to induce ALI in rats. L6H9 pretreatment attenuates LPS-induced pathological variations in lung tissue and pulmonary edema. LPS instillation enhanced lung microvascular permeability, thereby causing inflammatory cells flow into bronchoalveolar lavage fluid (BALF). However, L6H9 inhibited the LPS-induced upregulation of total protein concentration and the number of inflammatory cells in BALF. In the meantime, macrophages infiltration in lung tissue induced by LPS was also mitigated by L6H9 treatment. Furthermore, L6H9 suppressed LPS-induced inflammatory cytokines expression in BALF, serum, and lung tissue. It is noteworthy that LPS-induced MD2/TLR4 complex formation was inhibited by L6H9 in lung tissue. On the whole, these results show that L6H9 can attenuate LPS-induced ALI in vivo by targeting MD2. Our study provide new candidate for the treatment of ALI.

Myeloid Differentiation Protein 2 Mediates Angiotensin II-Induced Liver Inflammation and Fibrosis in Mice.

Angiotensin II (Ang II) participates in the pathogenesis of liver injury. Our previous publications reported that myeloid differentiation protein 2 (MD2) mediates Ang II-induced cardiac and kidney inflammation by directly binding to Ang II. Thus, we hypothesize that MD2 is critical to Ang II-induced liver injury. Subcutaneous injections of Ang II for 8 weeks were adopted to build the liver injury model. With a specific MD2 inhibitor L6H21 and MD2 knockout mice, we reported that MD2 inhibition and knockout significantly mitigate liver inflammation and fibrosis in mice injected with Ang II. To be more specific, the functional and pathological damages induced by Ang II were mitigated by L6H21 or MD2 knockout. MD2 knockout or L6H21 administration inhibited the Ang II-induced upregulation of fibrosis markers, inflammatory cytokines, and adhesion molecules in gene or protein levels. The activation of NF-κB and Extracellular signal-regulated kinases (ERK) induced by Ang II was also reversed by L6H21 treatment or MD2 deficiency. Note that the co-immunoprecipitation study showed that L6H21 downregulated the ANG II-induced toll-like receptor 4 (TLR4)/MD2 complex in liver tissues while having no effects on MD2 expression. Our results reported the critical role of MD2 in the progress of liver injury and suggested that MD2 is a potential therapeutic target for liver injury.