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Neutrophils and their production of neutrophil extracellular traps (NETs) significantly contribute to neuroinflammation and brain damage after intracerebral hemorrhage (ICH). Although Akebia saponin D (ASD) demonstrates strong anti‐inflammatory activities and blood–brain barrier permeability, its role in regulating NETs formation and neuroinflammation following ICH is uncharted. Our research focused on unraveling the influence of ASD on neuroinflammation mediated by NETs and the mechanisms involved. We found that increased levels of peripheral blood neutrophils post‐ICH are correlated with worse prognostic outcomes. Through network pharmacology, we identified ASD as a promising therapeutic target for ICH. ASD administration significantly improved neurobehavioral performance and decreased NETs production in neutrophils. Furthermore, ASD was shown to upregulate the membrane protein NTSR1 and activate the cAMP signaling pathway, confirmed through transcriptome sequencing, western blot, and immunofluorescence. Interestingly, the NTSR1 inhibitor SR48692 significantly nullified ASD's anti‐NETs effects and dampened cAMP pathway activation. Mechanistically, suppression of PKAc via H89 negated ASD's anti‐NETs effects but did not affect NTSR1. Our study suggests that ASD may reduce NETs formation and neuroinflammation, potentially involving the NTSR1/PKAc/PAD4 pathway post‐ICH, underlining the potential of ASD in mitigating neuroinflammation through its anti‐NETs properties. [ABSTRACT FROM AUTHOR]

Endocytosis plays key roles during infection of plant‐pathogenic fungi, but its regulatory mechanisms are still largely unknown. Here, we identified a putative endocytosis‐related gene, PAL1, which was highly expressed in appressorium of Magnaporthe oryzae, and was found to be important for appressorium formation and maturation. Deletion of PAL1 significantly reduced the virulence of M. oryzae due to defects in appressorial penetration and invasive growth in host cells. The Pal1 protein interacted and colocalized with the endocytosis protein Sla1, suggesting it is involved in endocytosis. The Δpal1 mutant was significantly reduced in appressorium formation, which was recovered by adding exogenous cAMP and 3‐isobutyl‐1‐methylxanthine (IBMX). Moreover, the phosphorylation level of Pmk1 in Δpal1 was also reduced, suggesting Pal1 functions upstream of both the cAMP and Pmk1 signalling pathways. As a consequence, the utilization of glycogen and lipid, appressorial autophagy, actin ring formation, localization of septin proteins, as well as turgor accumulation were all affected in the Δpal1 mutant. Taken together, Pal1 regulates cAMP and the Pmk1 signalling pathway for appressorium formation and maturation to facilitate infection of M. oryzae. [ABSTRACT FROM AUTHOR]

The current study aimed to investigate the mechanism by which miR‐454 influences the progression of heart failure (HF) in relation to the neural precursor cell expressed, developmentally downregulated 4‐2 (NEDD4‐2)/tropomyosin receptor kinase A (TrkA)/cyclic adenosine 3',5'‐monophosphate (cAMP) axis. Sprague‐Dawley rats were used to establish a HF animal model via ligation of the left anterior descending branch of the coronary artery. The cardiomyocyte H9c2 cells were treated with H2O2 to stimulate oxidative stress injury in vitro. RT‐qPCR and Western blot assay were subsequently performed to determine the expression patterns of miR‐454, NEDD4‐2, TrkA, apoptosis‐related proteins and cAMP pathway markers. Dual‐luciferase reporter gene assay coupled with co‐immunoprecipitation was performed to elucidate the relationship between miR‐454, NEDD4‐2 and TrkA. Gain‐ or loss‐of‐function experiments as well as rescue experiments were conducted via transient transfection (in vitro) and adenovirus infection (in vivo) to examine their respective functions on H9c2 cell apoptosis and myocardial damage. Our results suggested that miR‐454 was aberrantly downregulated in the context of HF, while evidence was obtained suggesting that it targeted NEDD4‐2 to downregulate NEDD4‐2 in cardiomyocytes. miR‐454 exerted anti‐apoptotic and protective effects on cardiomyocytes through inhibition of NEDD4‐2, while NEDD4‐2 stimulated ubiquitination and degradation of TrkA protein. Furthermore, miR‐454 activated the cAMP pathway via the NEDD4‐2/TrkA axis, which ultimately suppressed cardiomyocyte apoptosis and attenuated myocardial damage. Taken together, the key findings of the current study highlight the cardioprotective role of miR‐454, which is achieved through activation of the cAMP pathway by impairing NEDD4‐2‐induced TrkA ubiquitination. [ABSTRACT FROM AUTHOR]

The melanocortin 1 receptor gene is a main determinant of human pigmentation, and a melanoma susceptibility gene, because its variants that are strongly associated with red hair color increase melanoma risk. To test experimentally the association between melanocortin 1 receptor genotype and melanoma susceptibility, we compared the responses of primary human melanocyte cultures naturally expressing different melanocortin 1 receptor variants to α-melanocortin and ultraviolet radiation. We found that expression of 2 red hair variants abolished the response to α-melanocortin and its photoprotective effects, evidenced by lack of functional coupling of the receptor, and absence of reduction in ultraviolet radiation-induced hydrogen peroxide generation or enhancement of repair of DNA photoproducts, respectively. These variants had different heterozygous effects on receptor function. Microarray data confirmed the observed differences in responses of melanocytes with functional vs. nonfunctional receptor to α-melanocortin and ultraviolet radiation, and identified DNA repair and antioxidant genes that are modulated by α-melanocortin. Our findings highlight the molecular mechanisms by which the melanocortin 1 receptor genotype controls genomic stability of and the mutagenic effect of ultraviolet radiation on human melanocytes. [ABSTRACT FROM AUTHOR]

Nefiracetam has been reported to increase intracellular cyclic AMP levels and enhance calcium channel current. Since the cAMP cascade is involved in the development of drug dependence, we investigated whether nefiracetam attenuates the methamphetamine (MAP)-induced discriminative responses in rats. Nefiracetam (50 mg/kg) inhibited MAP-induced discriminative responses. Furthermore, rolipram, raclopride, and L-745870, all of which can enhance cAMP activity, disrupted MAP-paired lever press of rats. Nifedipine and neomycin, which are blockers of voltage-sensitive calcium channels (VSCCs), decreased MAP-induced discriminative responses. However, pretreatment of these VSCC blockers failed to affect the inhibitory effects of nefiracetam on MAP-induced discriminative responses. Our findings suggested that nefiracetam inhibits MAP-induced discriminative responses, which may be at least partly associated with the changes in intracellular cAMP levels. [ABSTRACT FROM AUTHOR]

Regulation of annexing concentration and localization were investigated in thyroid tissues of hypothyroid [methylthiouracil (MeSur) treatment], euthyroid (control) and hyperthyroid [thyroxine (T4) treatment] rats. A low level of circulating thyroid hormones induces a decrease of total thyroid calcium-binding protein concentration when compared with the concentration in unstimulated animals. Conversely, concentrations of annexing I, II and V increase. The accumulation of these proteins in two subcellular compartments (cytosolic and particulate fractions) can be reversed by addition of thyroid hormones. The finding of a specific increase in annexing concentration in thyroid-hormone-deficient rats, with a general decrease of the total calcium-binding protein content points to a very important role of these proteins in the cells Furthermore, hyperthyroidism gives opposite results. To investigate the transduction pathway of annexing I-, II- and V-induced biosynthesis by thyroid hormones in thyroid glands, we used cultured pig thyroid cells as in vitro model system. In previous work, we have shower that annexing concentrations and localization are under TSH control via the adenylate cyclase pathway. In the presence of MeSur (in the culture medium), the protein-binding iodine remains low, indicative of weak thyroid hormone synthesis (data not shown) and that the annexing content is unchanged. These results suggest that, in thyroid tissue, an indirect mechanism links thyroid hormones to annexing expressions via the TSH feed-back loop, and excludes autocrine regulation. [ABSTRACT FROM AUTHOR]