Meldonium, as a potential neuroprotective agent, promotes neuronal survival by protecting mitochondria in cerebral ischemia-reperfusion injury.

BACKGROUND: Stroke is a globally dangerous disease capable of causing irreversible neuronal damage with limited therapeutic options. Meldonium, an inhibitor of carnitine-dependent metabolism, is considered an anti-ischemic drug. However, the mechanisms through which meldonium improves ischemic injury and its potential to protect neurons remain largely unknown. METHODS: A rat model with middle cerebral artery occlusion (MCAO) was used to investigate meldonium's neuroprotective efficacy in vivo. Infarct volume, neurological deficit score, histopathology, neuronal apoptosis, motor function, morphological alteration and antioxidant capacity were explored via 2,3,5-Triphenyltetrazolium chloride staining, Longa scoring method, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, rotarod test, transmission electron microscopy and Oxidative stress index related kit. A primary rat hippocampal neuron model subjected to oxygen-glucose deprivation reperfusion was used to study meldonium's protective ability in vitro. Neuronal viability, mitochondrial membrane potential, mitochondrial morphology, respiratory function, ATP production, and its potential mechanism were assayed by MTT cell proliferation and cytotoxicity assay kit, cell-permeant MitoTracker® probes, mitochondrial stress, real-time ATP rate and western blotting. RESULTS: Meldonium markedly reduced the infarct size, improved neurological function and motor ability, and inhibited neuronal apoptosis in vivo. Meldonium enhanced the morphology, antioxidant capacity, and ATP production of mitochondria and inhibited the opening of the mitochondrial permeability transition pore in the cerebral cortex and hippocampus during cerebral ischemia-reperfusion injury (CIRI) in rats. Additionally, meldonium improved the damaged fusion process and respiratory function of neuronal mitochondria in vitro. Further investigation revealed that meldonium activated the Akt/GSK-3ß signaling pathway to inhibit mitochondria-dependent neuronal apoptosis. CONCLUSION: Our study demonstrated that meldonium shows a neuroprotective function during CIRI by preserving the mitochondrial function, thus prevented neurons from apoptosis.

A genetic variant in the TAPBP gene enhances cervical cancer susceptibility by increasing m6A modification.

Genetic variants can affect gene expression by altering the level of N6-methyladenosine (m6A) modifications. A better understanding of the association of these genetic variants with susceptibility to cervical cancer (CC) can promote advances in disease screening and treatment. Genome-wide identification of m6A-associated functional SNPs for CC was performed using the TCGA and JENGER databases, incorporating the data from RNA-seq and MeRIP-seq. The screened risk-associated SNP rs1059288 (A>G), which is located in the 3' UTR of TAPBP, was further validated in a case-control study involving 921 cases and 1077 controls. The results revealed a significant association between rs1059288 and the risk of CC (OR 1.48, 95% CI 1.13-1.92). Mechanistically, the presence of the risk G allele of rs1059288 was associated with increased m6A modification of TAPBP compared with the A allele. This modification was facilitated by the m6A methyltransferase METTL14 and the reading protein YTHDF2. Immunohistochemical staining of tissue microarrays containing 61 CC and 45 normal tissues showed an overexpression of TAPBP in CC. Furthermore, the upregulation of TAPBP promoted the growth and migration of CC cells as well as tumor-forming ability, inhibited apoptosis, and conferred increased resistance to commonly used chemotherapeutic drugs such as bleomycin, cisplatin, and doxorubicin. Knockdown of TAPBP inhibited the JAK/STAT/MICB signaling pathway in CC cells and upregulated certain immune genes including ISG15, IRF3, PTPN6, and HLA-A. These findings offer insights into the involvement of genetic variations in TAPBP in the development and progression of CC.

Novel energy optimizer, meldonium, rapidly restores acute hypobaric hypoxia-induced brain injury by targeting phosphoglycerate kinase 1.

BACKGROUND: Acute hypobaric hypoxia-induced brain injury has been a challenge in the health management of mountaineers; therefore, new neuroprotective agents are urgently required. Meldonium, a well-known cardioprotective drug, has been reported to have neuroprotective effects. However, the relevant mechanisms have not been elucidated. We hypothesized that meldonium may play a potentially novel role in hypobaric hypoxia cerebral injury. METHODS: We initially evaluated the neuroprotection efficacy of meldonium against acute hypoxia in mice and primary hippocampal neurons. The potential molecular targets of meldonium were screened using drug-target binding Huprot™ microarray chip and mass spectrometry analyses after which they were validated with surface plasmon resonance (SPR), molecular docking, and pull-down assay. The functional effects of such binding were explored through gene knockdown and overexpression. RESULTS: The study clearly shows that pretreatment with meldonium rapidly attenuates neuronal pathological damage, cerebral blood flow changes, and mitochondrial damage and its cascade response to oxidative stress injury, thereby improving survival rates in mice brain and primary hippocampal neurons, revealing the remarkable pharmacological efficacy of meldonium in acute high-altitude brain injury. On the one hand, we confirmed that meldonium directly interacts with phosphoglycerate kinase 1 (PGK1) to promote its activity, which improved glycolysis and pyruvate metabolism to promote ATP production. On the other hand, meldonium also ameliorates mitochondrial damage by PGK1 translocating to mitochondria under acute hypoxia to regulate the activity of TNF receptor-associated protein 1 (TRAP1) molecular chaperones. CONCLUSION: These results further explain the mechanism of meldonium as an energy optimizer and provide a strategy for preventing acute hypobaric hypoxia brain injury at high altitudes.

Enantioselective toxicity of the neonicotinoid dinotefuran on honeybee (Apis mellifera) larvae.

The threat of neonicotinoids to insect pollinators, particularly honeybees (Apis mellifera), is a global concern, but the risk of chiral neonicotinoids to insect larvae remains poorly understood. In the current study, we evaluated the acute and chronic toxicity of dinotefuran enantiomers to honeybee larvae in vitro and explored the mechanism of toxicity. The results showed that the acute median lethal dose (LD50) of S-dinotefuran to honeybee larvae was 30.0 µg/larva after oral exposure for 72 h, which was more toxic than rac-dinotefuran (92.7 µg/larva) and R-dinotefuran (183.6 µg/larva). Although the acute toxicity of the three forms of dinotefuran to larvae was lower than that to adults, chronic exposure significantly reduced larval survival, larval weight, and weight of newly emerged adults. Analysis of gene expression and hormone titer indicated that dinotefuran affects larval growth and development by interfering with nutrient digestion and absorption and the molting system. Analysis of hemolymph metabolome further revealed that disturbances in the neuroactive ligand-receptor interaction pathway and energy metabolism are the key mechanisms of dinotefuran toxicity to bee larvae. In addition, melatonin and vitellogenin are used by larvae to cope with dinotefuran-induced oxidative stress. Our results contribute to a comprehensive understanding of dinotefuran damage to bees and provide new insights into the mechanism of enantioselective toxicity of insecticides to insect larvae.

Toxic effects of acaricide fenazaquin on development, hemolymph metabolome, and gut microbiome of honeybee (Apis mellifera) larvae.

Fenazaquin, a potent insecticide widely used to control phytophagous mites, has recently emerged as a potential solution for managing Varroa destructor mites in honeybees. However, the comprehensive impact of fenazaquin on honeybee health remains insufficiently understood. Our current study investigated the acute and chronic toxicity of fenazaquin to honeybee larvae, along with its influence on larval hemolymph metabolism and gut microbiota. Results showed that the acute median lethal dose (LD50) of fenazaquin for honeybee larvae was 1.786 µg/larva, and the chronic LD50 was 1.213 µg/larva. Although chronic exposure to low doses of fenazaquin exhibited no significant effect on larval development, increasing doses of fenazaquin resulted in significant increases in larval mortality, developmental time, and deformity rates. At the metabolic level, high doses of fenazaquin inhibited nucleotide, purine, and lipid metabolism pathways in the larval hemolymph, leading to energy metabolism disorders and physiological dysfunction. Furthermore, high doses of fenazaquin reduced gut microbial diversity and abundance, characterized by decreased relative abundance of functional gut bacterium Lactobacillus kunkeei and increased pathogenic bacterium Melissococcus plutonius. The disrupted gut microbiota, combined with the observed gut tissue damage, could potentially impair food digestion and nutrient absorption in the larvae. Our results provide valuable insights into the complex and diverse effects of fenazaquin on honeybee larvae, establishing an important theoretical basis for applying fenazaquin in beekeeping.

Proteomics profiling of the honeybee parasite Tropilaelaps mercedesae across post-embryonic development.

Tropilaelaps mercedesae, an ectoparasitic mite of honeybees, is currently a severe health risk to Apis mellifera colonies in Asia and a potential threat to the global apiculture industry. However, our understanding of the physiological and developmental regulation of this pest remains significantly insufficient. Using ultra-high resolution mass spectrometry, we provide the first comprehensive proteomic profile of T. mercedesae spanning its entire post-embryonic ontogeny, including protonymphs, deutonymphs, mature adults, and reproductive mites. Consequently, a total of 4,422 T. mercedesae proteins were identified, of which 2,189 proteins were significantly differentially expressed (FDR < 0.05) throughout development and maturation. Our proteomic data provide an important resource for understanding the biology of T. mercedesae, and will contribute to further research and effective control of this devastating honeybee pest.

Potential Common Mechanisms of Cytotoxicity Induced by Organophosphorus Pesticides via NLRP3 Inflammasome Activation.

The Multi-Threat Medical Countermeasure (MTMC) technique is crucial for developing common biochemical signaling pathways, molecular mediators, and cellular processes. This study revealed that the Nod-like receptor 3 (NLRP3) inflammasome pathway may be a significant contributor to the cytotoxicity induced by various organophosphorus pesticides (OPPs). The study demonstrated that exposure to six different types of OPPs (paraoxon, dichlorvos, fenthion, dipterex, dibrom, and dimethoate) led to significant cytotoxicity in BV2 cells, which was accompanied by increased expression of NLRP3 inflammasome complexes (NLRP3, ASC, Caspase-1) and downstream inflammatory cytokines (IL-1ß, IL-18), in which the order of cytotoxicity was dichlorvos > dipterex > dibrom > paraoxon > fenthion > dimethoate, based on the IC50 values of 274, 410, 551, 585, 2,158, and 1,527,566 µM, respectively. The findings suggest that targeting the NLRP3 inflammasome pathway could be a potential approach for developing broad-spectrum antitoxic drugs to combat multi-OPPs-induced toxicity. Moreover, inhibition of NLRP3 efficiently protected the cells against cytotoxicity induced by these six OPPs, and the expression of NLRP3, ASC, Caspase-1, IL-1ß, and IL-18 decreased accordingly. The order of NLRP3 affinity for OPPs was dimethoate > paraoxon > dichlorvos > dibrom > (fenthion and dipterex) based on K D values of 89.8, 325, 1,460, and 2,690 µM, respectively. Furthermore, the common molecular mechanism of NLRP3-OPPs was clarified by the presence of toxicity effector groups (benzene ring, nitrogen/oxygen-containing functional group); =O, -O-, or =S (active) groups; and combination residues (Gly271, Asp272). This finding provided valuable insights into exploring the common mechanisms of multiple threats and developing effective therapeutic strategies to prevent OPPs poisoning.

Surface functionalization of exosomes for chondrocyte-targeted siRNA delivery and cartilage regeneration.

Osteoarthritis (OA) is the most prevalent degenerative cartilage disease, but no effective treatment is currently available to ameliorate the dysregulation of cartilage catabolism. Cartilage degeneration is closely related to the change in the physiology of chondrocytes: for example, chondrocytes of the OA patients overexpress matrix metallopeptidase 13 (MMP13), a.k.a. collagenase 3, which damages the extracellular matrix (ECM) of the cartilage and deteriorate the disease progression. Inhibiting MMP13 has shown to be beneficial for OA treatments, but delivering therapeutics to the chondrocytes embedded in the dense cartilage is a challenge. Here, we engineered the exosome surface with the cartilage affinity peptide (CAP) through lipid insertion to give chondrocyte-targeting exosomes, CAP-Exo, which was then loaded with siRNA against MMP13 (siMMP13) in the interior to give CAP-Exo/siMMP13. Intra-articular administration of CAP-Exo/siMMP13 reduced the MMP13 level and increased collagen COL2A1 and proteoglycan in cartilage in a rat model of anterior cruciate ligament transection (ACLT)-induced OA. Proteomic analysis showed that CAP-Exo/siMMP13 treatment restored the altered protein levels in the IL-1ß-treated chondrocytes. Taken together, a facile exosome engineering method enabled targeted delivery of siRNA to chondrocytes and chondrocyte-specific silencing of MMP13 to attenuate cartilage degeneration.

Long-term 4-nonylphenol exposure drives cervical cell malignancy through MAPK-mediated ferroptosis inhibition.

4-NP (4-nonylphenol), a prevalent environmental endocrine disruptor with estrogenic properties, is commonly detected in drinking water and food sources. It poses a significant risk of endocrine disruption, thereby influencing the onset and progression of diverse diseases, including tumorigenesis. However, its specific impact on cervical cancer remains to be fully elucidated. Our study focused on the biological effects of sustained exposure to low-dose 4-NP on human normal cervical epithelial cells (HcerEpic). After a continuous 30-week exposure to 4-NP, the treated cells exhibited a significant malignant transformation, whereas the solvent control group showed limited malignant phenotypes. Subsequent analyses of the metabolomic profiles of the transformed cells unveiled marked irregularities in glutathione metabolism and unsaturated fatty acid metabolism. Analyses of transcriptomic profiles revealed significant activation of the MAPK signaling pathway and suppression of ferroptosis processes in these cells. Furthermore, the expression of MT2A was significantly upregulated following 4-NP exposure. Knockdown of MT2A restored the aberrant activation of the MAPK signaling pathway, elevated antioxidant capacity, ferroptosis inhibition, and ultimately the development of malignant phenotypes that induced by 4-NP in the transformed cells. Mechanistically, MT2A increased cellular antioxidant capabilities and facilitated the removal of toxic iron ions by enhancing the phosphorylation of ERK1/2 and JNK MAPK pathways. The administration of activators and inhibitors of the MAPK pathway confirmed that the MAPK pathway mediated the 4-NP-induced suppression of ferroptosis and, ultimately, the malignant transformation of cervical epithelial cells. Overall, our findings elucidated a dynamic molecular transformation induced by prolonged exposure to 4-NP, and delineated comprehensive biological perspectives underlying 4-NP-induced cervical carcinogenesis. This offers novel theoretical underpinnings for the assessment of the carcinogenic risks associated with 4-NP.

Chondrocyte-Targeted Delivery System of Sortase A-Engineered Extracellular Vesicles Silencing MMP13 for Osteoarthritis Therapy.

Targeted drug delivery and the reduction of off-target effects are crucial for the promising clinical application of nucleic acid drugs. To address this challenge, a new approach for treating osteoarthritis (OA) that accurately delivers antisense oligonucleotides (ASO) targeting matrix metalloproteinase-13 (ASO-MMP13) to chondrocytes, is developed. Small extracellular vesicles (exos) are ligated with chondrocyte affinity peptide (CAP) using Sortase A and subsequently incubated with cholesterol-modified ASO-MMP13 to construct a chondrocyte-targeted drug delivery exo (CAP-exoASO). Compared with exos without CAP (ExoASO), CAP-exoASOs attenuate IL-1ß-induced chondrocyte damage and prolong the retention time of ASO-MMP13 in the joint without distribution in major organs following intra-articular injection. Notably, CAP-exoASOs decrease MMP13 expression (P < 0.001) and upregulate COL2A1 expression (P = 0.006), resulting in reorganization of the cartilage matrix and alleviation of progression in the OA model. Furthermore, the Osteoarthritis Research Society International (OARSI) score of articular cartilage tissues treated with CAP-exoASO is comparable with that of healthy rats (P = 0.148). A mechanistic study demonstrates that CAP-exoASO may reduce inflammation by suppressing the IL-17 and TNF signaling pathways. Based on the targeted delivery effect, CAP-exoASOs successfully accomplish cartilage repair and have considerable potential for development as a promising therapeutic modality for satisfactory OA therapy.

Comprehensive Analysis of the SUMO-related Signature: Implication for Diagnosis, Prognosis, and Immune Therapeutic Approaches in Cervical Cancer.

SUMOylation, an important post-translational protein modification, plays a critical role in cancer development and immune processes. This study aimed to construct diagnostic and prognostic models for cervical cancer (CC) using SUMOylation-related genes (SRGs) and explore their implications for novel clinical therapies. We analyzed the expression profiles of SRGs in CC patients and identified 15 SRGs associated with CC occurrence. After the subsequent qPCR verification of 20 cases of cancer and adjacent tissues, 13 of the 15 SRGs were differentially expressed in cancer tissues. Additionally, we identified molecular markers associated with the prognosis and recurrence of CC patients, based on SRGs. Next, a SUMOScore, based on SRG expression patterns, was generated to stratify patients into different subgroups. The SUMOScore showed significant associations with the tumor microenvironment, immune function features, immune checkpoint expression, and immune evasion score in CC patients, highlighting the strong connection between SUMOylation factors and immune processes. In terms of immune therapy, our analysis identified specific chemotherapy drugs with higher sensitivity in the subgroups characterized by high and low SUMOScore, indicating potential treatment options. Furthermore, we conducted drug sensitivity analysis to evaluate the response of different patient subgroups to conventional chemotherapy drugs. Our findings revealed enrichment of immune-related pathways in the low-risk subgroup identified by the prognostic model. In conclusion, this study presents diagnostic and prognostic models based on SRGs, accompanied by a comprehensive index derived from SRGs expression patterns. These findings offer valuable insights for CC diagnosis, prognosis, treatment, and immune-related analysis.

Life-history stage determines the diet of ectoparasitic mites on their honey bee hosts.

Ectoparasitic mites of the genera Varroa and Tropilaelaps have evolved to exclusively exploit honey bees as food sources during alternating dispersal and reproductive life history stages. Here we show that the primary food source utilized by Varroa destructor depends on the host life history stage. While feeding on adult bees, dispersing V. destructor feed on the abdominal membranes to access to the fat body as reported previously. However, when V. destructor feed on honey bee pupae during their reproductive stage, they primarily consume hemolymph, indicated by wound analysis, preferential transfer of biostains, and a proteomic comparison between parasite and host tissues. Biostaining and proteomic results were paralleled by corresponding findings in Tropilaelaps mercedesae, a mite that only feeds on brood and has a strongly reduced dispersal stage. Metabolomic profiling of V. destructor corroborates differences between the diet of the dispersing adults and reproductive foundresses. The proteome and metabolome differences between reproductive and dispersing V. destructor suggest that the hemolymph diet coincides with amino acid metabolism and protein synthesis in the foundresses while the metabolism of non-reproductive adults is tuned to lipid metabolism. Thus, we demonstrate within-host dietary specialization of ectoparasitic mites that coincides with life history of hosts and parasites.

Artichoke (Cynara scolymus L.) water extract alleviates palmitate-induced insulin resistance in HepG2 hepatocytes via the activation of IRS1/PI3K/AKT/FoxO1 and GSK-3ß signaling pathway.

BACKGROUND: Artichoke (Cynara scolymus L.) is a typical element of a traditional Mediterranean diet and has potential health advantages for insulin resistance (IR) and type 2 diabetes mellitus (T2DM). This study aims to evaluate the effect and underlying mechanism of artichoke water extract (AWE) on palmitate (PA)-induced IR in human hepatocellular carcinoma (HepG2) cells. METHODS: The effect of AWE on cell viability was determined using CCK8 assay. Cellular glucose uptake, glucose consumption, glucose production, and glycogen content were assessed after AWE treatment. The gene expression and protein levels were examined by real-time polymerase chain reaction (qRT-PCR) and western blotting. RESULTS: The results showed that AWE dose-dependently increased cell viability in IR HepG2 cells (P < 0.01). AWE treatment significantly promoted glucose uptake and consumption, decreased glucose production, and increased the cellular glycogen content in IR HepG2 cells (P < 0.01). Mechanistically, AWE elevated the phosphorylation and total protein levels of major insulin signaling molecules in IR HepG2 cells, which resulted in a decrease in the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) and the inhibition of glycogen synthase (GS) phosphorylation in IR HepG2 cells. Furthermore, the protective effect of AWE on IR HepG2 cells might be ascribed to the inhibition of the endoplasmic reticulum (ER) stress. CONCLUSION: We conclude that AWE may improve glucose metabolism by regulating IRS1/PI3K/AKT/FoxO1 and GSK-3ß signaling associated with the inhibition of ER stress in IR HepG2 cells induced by PA.

LINC00426, a novel m6A-regulated long non-coding RNA, induces EMT in cervical cancer by binding to ZEB1.

PURPOSE: To explore the function and molecular mechanism of LINC00426 in Cervical Cancer (CC), and to explore the clinical treatment strategy of LINC00426 for CC. METHODS: Bioinformatics analysis was used to explore the expression of LINC00426 and patient prognosis of CC. Cell function experiments were conducted to explore the potential effect of LINC00426 on CC malignant phenotypes. The difference in m6A modification level between the high and low expression groups of LINC00426 was analyzed by detecting the total m6A level. The luciferase reporter assay was used to confirm the binding of miR-200a-3p to LINC00426. The RIP assay was used to confirm the binding of LINC00426 to ZEB1. Cell viability assay was performed to detect the effect of LINC00426 on cellular drug resistance. RESULTS: LINC00426 is up-regulated in CC, which can enhance the proliferation, migration and invasion of CC cells. METTL3 promotes the expression of LINC00426 by m6A methylation modification. In addition, the LINC00426/miR-200a-3p/ZEB1 axis affects the proliferation, migration, and invasion of CC by regulating the expression of EMT markers. Through the detection of cell viability, we observed that overexpression LINC00426 in cells resulted in resistance to cisplatin and bleomycin, and more sensitive to imatinib. CONCLUSION: LINC00426 is a cancer-promoting lncRNA related to m6A modification. The process of EMT in CC is regulated by the LINC00426/miR-200a/3p/ZEB1 axis. LINC00426 can affect the sensitivity of CC cells to chemotherapy drugs, and is expected to become a therapeutic target for CC.

Post-transcriptional regulation of tumor suppressor gene lncRNA CARMN via m6A modification and miRNA regulation in cervical cancer.

PURPOSE: The abnormal regulation of lncRNA CARMN has been proved to be a tumor suppressor gene of cervical cancer (CC). However, its role in CC is still elusive. The regulation of CARMN post-transcriptional level by m6A modification and miRNA has not been studied. This study aims to analyze the molecular mechanism of m6A modification and miRNA on the abnormal expression of CARMN in CC cells, so as to provide a new theoretical basis for the diagnosis and treatment of CC. METHODS: MeRIP-seq was used to identify the differential m6A-modified genes between tumor and normal cervical tissues. RT-qPCR assay was used to detect gene expression levels in tissues or cells. The m6A modification sites of CARMN was predicted by bioinformatics, and the modification of m6A and its regulatory effect on CARMN were analyzed by MeRIP-qPCR, Actinomycin D assay and RIP assay. RIP-microarray combined with bioinformatics methods to screen miRNAs that may target CARMN. The regulation mechanism between miRNA and CARMN was verified by RT-qPCR, nucleo-plasmic separation assay, mRNA stability assay, dual-luciferase reporter assay, and in vivo experiments. RESULTS: MeRIP-seq found that CARMN is a significant different gene in the abundance of m6A in CC, and the modification level of m6A in CC tissues was higher than that in normal cervical tissues. Further, this study verified that m6A reader YTHDF2 could recognize m6A-modified CARMN and promote its degradation in CC cells. miR-21-5p was proved to be the downstream target gene of CARMN, and miR-21-5p could negatively regulate the expression of CARMN. Further experiments showed that miR-21-5p could directly bind to CARMN and lead to the degradation of CARMN. The in vivo experimental results indicated that the level of miR-21-5p in the overexpressed CARMN group was significantly lower than that in the control group. CONCLUSION: m6A modification and miR-21-5p play important roles in promoting the occurrence and development of tumors by regulating CARMN, provide new potential targets for the treatment of CC.

Insights into the pharmacodynamics and pharmacokinetics of meldonium after exposure to acute high altitude.

Objective: Meldonium, a well-known cardioprotective drug, has been reported to be protective against pulmonary injury at high altitudes; however, the pharmacodynamics of meldonium in other vital organs under acute high-altitude injury are less investigated and the related pharmacokinetics have not been fully elucidated. Methods and Results: The present study examined the basic pharmacodynamics and pharmacokinetics (PK) in rat exposure to acute high-altitude hypoxia after intragastrical and intravenous pre-administration of meldonium. The results indicate that meldonium can improve acute hypoxia-induced pathological damage in brain and lung tissues, and restore blood biochemistry and routine blood index of heart, liver and kidney tissues under a simulated acute high-altitude environment. Furthermore, compared to the normoxia group, rats exposed to simulated high-altitude hypoxia and premedicated with intragastrical meldonium showed linear kinetics in the dose range of 25-100 mg/kg, with a significantly increase in the area under curve (AUC) and reduced clearance rate. No significant differences in these meldonium of PK parameters were observed with intravenous administration. Additionally, meldonium was involved in the regulation of succinic acid and 3-hydroxypropionic acid. Conclusion: These results will contribute to our understanding of the preclinical PK properties of meldonium and its acute high-altitude protective effects.

Differential responses of the seed germination of three functional groups to low temperature and darkness in a typical steppe, Northern China.

Seed germination is a key stage in the life history of plants, which has a crucial effect on plant community structure. Climate change has substantially altered the surface soil temperature and light availability, which can affect seed germination. However, whether the seed germination of different functional groups is affected by the interactions of light and temperature remains unclear. Under laboratory conditions, we examined the effects of low temperature and darkness, as well as their interaction, on the seed germination of 16 species belonging to three plant functional groups (annual and biennials, perennial grasses, and perennial forbs) in a typical steppe, Northern China. We found that low temperature had a significant negative effect on seed germination of all species. Low temperature significantly decreased the final germination percentage and germinative force of the three plant functional groups, and the germination duration of perennial grasses. Darkness significantly decreased the germinative force of perennial forbs and total seeds, and the germination duration of perennial grasses. The interactive effects of light and temperature on the seed final germination percentage and germinative force of perennial grass indicated that darkness strengthened the inhibitory effect of low temperature on the seed germination of the grass functional group. Our study indicate that the seed germination of different plant functional groups varied greatly in response to changing environmental conditions. Our results suggest that future climate change could alter the regeneration and species composition of plant communities through changing seed germination.

Water extract from artichoke ameliorates high-fat diet-induced non-alcoholic fatty liver disease in rats.

BACKGROUND: The "multiple-hit" hypothesis is currently the most widely accepted theory for non-alcoholic fatty liver disease (NAFLD) pathogenesis. The present study aimed to investigate the effects of the water extract of artichoke (WEA) on NAFLD and its underlying mechanism. METHODS: Rats were fed a high-fat diet (HFD) for 8 weeks to induce NAFLD and then treated with WEA at three doses (0.4, 0.8, and 1.6 g/kg body weight, BW) for 8 weeks. At the end of the intervention, serum biochemical parameters, hepatic antioxidant capacity, hepatic levels of pro-inflammatory cytokines, liver histopathology, hepatic inflammatory gene and lipid metabolism gene expression, and Akt and p-Akt (S473) protein levels were determined. RESULTS: The body weight, liver weight, liver triglyceride (TG) and serum levels of TG, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, glucose, and insulin were all significantly reduced in the WEA-treated groups (0.8 and 1.6 g/kg BW) compared with the HFD group (P < 0.01). A significant decrease in hepatic content of malondialdehyde (P < 0.01) and glutathione (P < 0.01), as well as a significant increase in liver superoxide dismutase activity (P < 0.01) were observed in WEA-treated groups (0.8 and 1.6 g/kg BW) compared to the HFD group. In addition, there was a marked decrease in the hepatic levels of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in the WEA-treated groups compared to the HFD group (P < 0.01). In line with these findings, the histopathology of the livers of rats treated with WEA (0.8 and 1.6 g/kg BW) showed a decrease in steatosis, ballooning, and lobular inflammation. Mechanistically, the reduced hepatic TG content might be related to the downregulation of lipogenic genes (SREBP1c, FASN, SCD1) and upregulation of lipolytic gene (PPARα), and the improved insulin signaling might be associated with the observed increase in antioxidant activity and reduction in inflammation in the WEA-treated groups. CONCLUSION: The hepatoprotective role of WEA in NAFLD may be attributed to its anti-steatotic, antioxidant, anti-inflammatory, and anti-insulin resistance effects.

Production of extracellular amylase contributes to the colonization of Bacillus cereus 0-9 in wheat roots.

BACKGROUND: Bacteria usually secrete a variety of extracellular enzymes to degrade extracellular macromolecules to meet their nutritional needs and enhance their environmental adaptability. Bacillus cereus 0-9, a biocontrol bacterial strain isolated from wheat roots, has three genes annotated as encoding amylases in the genome, but their functions are unknown, and whether they are involved in the colonization process of the bacterium remains to be further studied. METHODS: Mutant gene strains and fluorescently tagged strains were constructed by homologous recombination, and amylase protein was expressed in the prokaryotic Escherichia coli BL21(DE3) expression system. The iodine staining method was used to measure the activity of amylase proteins. We further observed the colonization abilities of the test strains in wheat roots through frozen section technology. RESULTS: The results showed that there were three amylase-encoding genes, amyC, amyP and amyS, in the B. cereus 0-9 genome. Among the three amylase encoding genes, only amyS produced extracellular amylase whose secretion was related to signal peptide at position 1-27. The AmyS protein encoded by the amyS gene is an α-amylase. The growth of Rhizoctonia cerealis was inhibited 84.7% by B. cereus 0-9, but the biocontrol ability of the ΔamyS strain decreased to 43.8% and that of ΔamyS/amyS was restored when the amyS gene was complemented. Furthermore, the biocontrol ability of the ΔamySec strain was decreased to 46.8%, almost the same as that of the ΔamyS mutant. Due to the deletion of the amyS gene, the colonization capacities of ΔamyS (RFP) and ΔamySec (RFP) in wheat roots decreased, while that of ΔamyS/amyS (RFP) was restored after the amyS gene was complemented, indicating that the amyS gene influences the colonization of B. cereus 0-9 in wheat roots. In addition, the colonization and biocontrol abilities of the mutant were restored after the addition of sugars, such as glucose and maltose. CONCLUSIONS: B. cereus 0-9 encodes three genes annotated as amylases, amyC, amyP and amyS. Only the deletion of the amyS gene with a signal peptide did not produce extracellular amylase. The AmyS protein encoded by the amyS gene is an α-amylase. Our results indicated that the amyS gene is closely related to the colonization abilities of B. cereus 0-9 in wheat roots and the biocontrol abilities of B. cereus 0-9 to fight against R. cerealis. The extracellular amylase produced by B. cereus 0-9 can hydrolyze starch and use glucose, maltose and other nutrients to meet the needs of bacterial growth. Therefore, it is very possible that the secretion and hydrolytic activities of extracellular amylase can promote the colonization of B. cereus 0-9 in wheat roots and play important roles in the prevention and control of plant diseases. Our results contribute to exploring the mechanisms of microbial colonization in plant roots.

Potential Common Mechanisms of Cytotoxicity Induced by Amide Herbicides via TRPA1 Channel Activation.

The "Multi-Threat Medical Countermeasure (MTMC)" strategy was proposed to develop a single drug with therapeutic efficacy against multiple pathologies or broad-spectrum protection against various toxins with common biochemical signals, molecular mediators, or cellular processes. This study demonstrated that cytotoxicity, expression of transient receptor potential cation channel subfamily A member 1 (TRPA1) mRNA, and intracellular calcium influx were increased in A549 cells exposed to amide herbicides (AHs), in which the order of cytotoxicity was metolachlor > acetochlor > propisochlor > alachlor > butachlor > propanil > pretilachlor, based on IC50 values of 430, 524, 564, 565, 619, 831, and 2333 µM, respectively. Inhibition/knockout of TRPA1 efficiently protected against cytotoxicity, decreased TRPA1 mRNA expression, and reduced calcium influx. The results suggested that the TRPA1 channel could be a key common target for AHs poisoning. The order of TRPA1 affinity for AHs was propanil > pretilachlor > metolachlor > (propiso/ala/aceto/butachlor), based on KD values of 16.2, 309, and 364 µM, respectively. The common molecular mechanisms of TRPA1-AHs interactions were clarified, including toxicity-effector groups (benzene ring, nitrogen/oxygen-containing functional groups, halogen) and residues involved in interactions (Lys787, Leu982). This work provides valuable information for the development of TRPA1 as a promising therapeutic target for broad-spectrum antitoxins.