EML4-ALK G1202R and EML4-ALK L1196M mutations induce crizotinib resistance in non-small cell lung cancer cells through activating epithelial-mesenchymal transition mediated by MDM2/MEK/ERK signal axis.

Crizotinib, as the first-generation of anaplastic lymphoma kinase (ALK) inhibitor, effectively improves the survival time of ALK-positive non-small cell lung cancer (NSCLC) patients. However, its efficacy is severely limited by drug resistance caused by secondary mutations. G1202R and L1196M are classical mutation sites located in ALK kinase domain. They may hinder the binding of ALK inhibitors to the target kinase domain, resulting in drug resistance in patients. However, the exact mechanism of drug resistance mediated by these mutations remains unclear. In this study, we aimed to evaluate how G1202R and L1196M mutations mediate crizotinib resistance. To explore the resistance mechanism, we constructed EML4-ALK G1202R and L1196M mutant cell lines with A549 cells. The results showed that the mutant cells exhibited significant epithelial-mesenchymal transition (EMT) and metastasis compared to control (A549-vector) or wild type (A549-EML4-ALK) cells. Subsequently, it was found that the occurrence of EMT was correlated to the high expression of murine double minute 2 (MDM2) protein and the activation of mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway in mutant cells. Down-regulation of MDM2 inhibited the activation of MEK/ERK pathway, thus reversed the EMT process and markedly increased the inhibitory effect of crizotinib on the growth of mutant cells. Collectively, resistance of ALK-positive NSCLC cells to crizotinib is induced by G1202R and L1196M mutations through activation of the MDM2/MEK/ERK signalling axis, promoting EMT process and metastasis. These findings suggest that the combination of MDM2 inhibitors and crizotinib could be a potential therapeutic strategy.

Mediation analysis of cognitive function in the relationship between pulmonary function and depression among middle-aged and older adults.

AIM: This study aims to explore the association between declining lung function and depression in middle-aged and older adults, with a special focus on the mediating role of cognitive function. METHODS: This study utilizes self-reported and physical examination data from 5345 individuals participating in the 2015 cycle of the China Health and Retirement Longitudinal Study (CHARLS) to explore the role of cognitive function changes in mediating the effects of diminished lung function on depression among middle-aged and older adults. RESULTS: Multivariate linear regression analysis revealed a positive correlation between pulmonary and cognitive functions (ß = 0.003, 95% CI: 0.002∼0.003, P < 0.01) and a negative correlation between cognitive function and depression (ß = -0.279, 95% CI: -0.330-0.228, P < 0.01). Cognitive function plays a mediating role in linking pulmonary function with depression, exhibiting a mediation effect of -0.0007 and a total effect of -0.0046, wherein the mediation effect contributes to 15.22% of the total effect. For females, the mediating effect of cognitive function was stronger (ß = -0.0013, 95% CI: -0.0018∼-0.0008, P < 0.01) than it was for males (ß = -0.0006, 95% CI: -0.0009∼-0.0003, P < 0.01). CONCLUSIONS: The study underscores the importance of monitoring lung and cognitive functions as interconnected factors contributing to the mental health of middle-aged and older adults. It suggests that interventions aimed at improving pulmonary health and cognitive function may help mitigate depressive symptoms among middle-aged and older adults. Further research is warranted to validate these findings across diverse cultural and demographic settings. Geriatr Gerontol Int 2024; ••: ••-••.

High Performance Organic Mixed Ionic-electronic Polymeric Conductor with Stability to Autoclave Sterilization.

We present a series of newly developed donor-acceptor (D-A) polymers designed specifically for organic electrochemical transistors (OECTs) synthesized by a straightforward route. All polymers exhibited accumulation mode behavior in OECT devices, and tuning of the donor comonomer resulted in a three-order-of-magnitude increase in transconductance. The best polymer gFBT-g2T, exhibited normalized peak transconductance (gm,norm) of 298±10.4 S cm-1 with a corresponding product of charge-carrier mobility and volumetric capacitance, µC*, of 847 F V-1 cm-1 s-1 and a µ of 5.76 cm2 V-1 s-1, amongst the highest reported to date. Furthermore, gFBT-g2T exhibited exceptional temperature stability, maintaining the outstanding electrochemical performance even after undergoing a standard (autoclave) high pressure steam sterilization procedure. Steam treatment was also found to promote film porosity, with the formation of circular 200 - 400 nm voids. These results demonstrate the potential of gFBT-g2T in p-type accumulation mode OECTs, and pave the way for the use in implantable bioelectronics for medical applications.

A brain-to-gut signal controls intestinal fat absorption.

Although fat is a crucial source of energy in diets, excessive intake leads to obesity. Fat absorption in the gut is prevailingly thought to occur organ-autonomously by diffusion1-3. Whether the process is controlled by the brain-to-gut axis, however, remains largely unknown. Here we demonstrate that the dorsal motor nucleus of vagus (DMV) plays a key part in this process. Inactivation of DMV neurons reduces intestinal fat absorption and consequently causes weight loss, whereas activation of the DMV increases fat absorption and weight gain. Notably, the inactivation of a subpopulation of DMV neurons that project to the jejunum shortens the length of microvilli, thereby reducing fat absorption. Moreover, we identify a natural compound, puerarin, that mimics the suppression of the DMV-vagus pathway, which in turn leads to reduced fat absorption. Photoaffinity chemical methods and cryogenic electron microscopy of the structure of a GABAA receptor-puerarin complex reveal that puerarin binds to an allosteric modulatory site. Notably, conditional Gabra1 knockout in the DMV largely abolishes puerarin-induced intestinal fat loss. In summary, we discover that suppression of the DMV-vagus-jejunum axis controls intestinal fat absorption by shortening the length of microvilli and illustrate the therapeutic potential of puerarin binding to GABRA1 in fat loss.

Oral administration of Lactobacillus plantarum expressing aCD11c modulates cellular immunity alleviating inflammatory injury due to Klebsiella pneumoniae infection.

BACKGROUND: Klebsiella pneumoniae (KP), responsible for acute lung injury (ALI) and inflammation of the gastrointestinal tract, is a zoonotic pathogen that poses a threat to livestock farming worldwide. Nevertheless, there is currently no validated vaccine to prevent KP infection. The development of mucosal vaccines against KP using Lactobacillus plantarum (L. plantarum) is an effective strategy. RESULTS: Firstly, the L. plantarum strains NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c were constructed via homologous recombination to express the aCD11c protein either inducibly or constitutively. Both NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c strains could enhance the adhesion and invasion of L. plantarum on bone marrow-derived dendritic cells (BMDCs), and stimulate the activation of BMDCs compared to the control strain NC8-pSIP409 in vitro. Following oral immunization of mice with NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c, the cellular, humoral, and mucosal immunity were significantly improved, as evidenced by the increased expression of CD4+ IL-4+ T cells in the spleen, IgG in serum, and secretory IgA (sIgA) in the intestinal lavage fluid (ILF). Furthermore, the protective effects of L. plantarum against inflammatory damage caused by KP infection were confirmed by assessing the bacterial loads in various tissues, lung wet/dry ratio (W/D), levels of inflammatory cytokines, and histological evaluation, which influenced T helper 17 (Th17) and regulatory T (Treg) cells in peripheral blood and lung. CONCLUSIONS: Both the inducible and constitutive L. plantarum strains NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c have been found to stimulate cellular and humoral immunity levels and alleviate the inflammatory response caused by KP infection. These findings have provided a basis for the development of a novel vaccine against KP.

The impact of social activities on mental health among older adults in China.

Background: Understand the current situation of social activities among older adults and its impact on mental health, providing policy basis and intervention measures to improve the mental health of the older adult. Method: Collect relevant data from 8,181 older adults aged ≥ 60 years old from the 2020 China Health and Retirement Longitudinal Study (CHARLS), constructing an analysis framework for social activities of older adults in China from three aspects: participation in social activities, number of social activities, frequency of social activities, and describe them, then analyzing the impact of social activities on their mental health using OLS and 2SLS regression models. This study also discusses the impact of eight social activities on the mental health of older adult people through subgroup. Result: Among 8,181 older adults aged 60 and above, 3,808 participated in social activities (56.24%), average number of social activities is 0.71, and average frequency of social activities is 1.31 times. The average score of mental health level measured by CES-D is 15.24 points. Participate in social activities can reduce the depression level of the older adult (ß = -0.352, 95%CI: -0.547~-0.158); the more social activities the older adult participate in, the lower the depression level of the older adult (ß = -0.214, 95%CI: -0.313~-0.115); the higher the frequency of participating in social activities, the lower the depression level of the older adult (ß = -0.133, 95%CI: -0.182~-0.083). In summary, social activities can improve the mental health level of the older adults in China. As for different types of social activities, visiting and socializing with friends, participating in club organization activities, playing mahjong, chess, cards, or going to community activity rooms and attending school or training courses can improve the mental health of the older adult. Discussion: The social activities in three dimensions among older adults in China need to be further improved, and participating in social activities can help improve their mental health. The conclusion provides important policy implications for encouraging and supporting older adults to participate in various social activities, increasing the number and frequency of older adult social activities, then help improving the mental health level of older adults.

Exploring the potential mechanism of Xiaojin Pill therapy for benign prostatic hyperplasia through metabolomics and gut microbiota analysis.

Background: Xiaojin Pill (XJP) is a traditional Chinese medicine prescribed for treating benign prostatic hyperplasia (BPH). It has been proven to have multiple effects, such as regulating sex hormone levels, exhibiting anti-tumor, anti-inflammatory, analgesic, and anti-platelet aggregation properties, and improving immunity. However, the material basis of XJP's therapeutic effect on BPH and its metabolic process in vivo remains to be clarified. At the same time, many microorganisms that exist in the urogenital tract, including those related to BPH, can also affect the health of the host. Methods: Using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), the chemical components of XJP were identified. A BPH model was created through bilateral testicular ablation and injections of testosterone propionate. A comprehensive evaluation of XJP efficacy was conducted using pathological ELISA, TUNEL, and immunohistochemical techniques. In addition, UPLC-MS metabolomics and 16S rRNA sequencing revealed the serum metabolic profile and intestinal microbiota composition. We performed a Spearman correlation coefficient analysis to highlight the interactions between "intestinal microbiota-serum factors" and "intestinal microbiota-metabolites." Results: XJP contains 91 compounds that alleviate pathologies of BPH in rats, decreasing prostate weight, index, and serum levels of Dihydrotestosterone (DHT), Prostate-Specific Antigen (PSA), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) levels. It inhibits prostatic epithelial cell apoptosis and downregulates Bax, TGF-ß1, and IGF-1 proteins in the caspase-3 pathway. Metabolomics studies have revealed 10 upregulated and 10 downregulated metabolites in treated rats, with 5-methylcytosine, uracil, and cytosine enriched in pyrimidine metabolism. L-arginine plays a pivotal role in metabolic pathways encompassing pyrimidine metabolism, arginine biosynthesis, and the mammalian target of rapamycin (mTOR) signaling pathway. 16S rRNA sequencing revealed that XJP optimized the diversity and balance of intestinal flora in BPH rats by decreasing the Bacteroidetes/Firmicutes (B/F) ratio, enhancing the beneficial bacteria, such as Eggerthellaceae, Anaerovoracaceae, and Romboutsia, and suppressing the dysfunctional bacteria, such as Atopobiaceae, Prevotellaceae_NK3B31_group, Dorea, and Frisingicoccus. According to the Spearman correlation coefficient analysis, Lactobacillus was found to be most associated with serum factors, whereas Romboutsia showed the highest correlation with metabolites. This finding suggests that XJP modulates pyrimidine metabolism disorders in BPH rats, a regulation that aligns closely with Romboutsia, Prevotellaceae_NK3B31_group, Lactobacillus, Chujaibacter, and Enterorhabdus, thereby providing valuable biological insights. Conclusion: In summary, these findings indicate that XJP possesses a synergistic anti-BHP effect through its multi-component, multi-target, multi-gut microbiota, and multi-metabolic pathway properties. The effect involves the regulation of sex hormone levels, growth factors, and the anti-epithelial cell apoptosis process. The modulation of specific gut microbiota by the host and the involvement of multiple metabolic pathways are likely one of the significant mechanisms of XJP in treating BPH. Notably, pyrimidine metabolism and the intestinal microbial ecosystem are closely intertwined in this process.

Two amino acid residues in the N-terminal region of the polymerase acidic protein determine the virulence of Eurasian avian-like H1N1 swine influenza viruses in mice.

Reassortant Eurasian avian-like H1N1 (rEA H1N1) viruses carrying the internal genes of H1N1/2009 virus have been circulating in pigs for more than 10 years and have caused sporadic human infections. The enhanced virulence phenotype of the rEA H1N1 viruses highlights potential risks to public health. However, the molecular mechanism underlying the viral pathogenicity of the currently circulating rEA H1N1 viruses remains unclear. In this study, we found that two naturally isolated rEA H1N1 swine influenza viruses, A/swine/Liaoning/FX38/2017 (FX38) and A/swine/Liaoning/SY72/2018 (SY72), possessed similar genetic characteristics but exhibited significantly different pathogenicity in a mouse model. Using reverse genetics, we demonstrated that amino acid mutations at positions 100 and 122 in the polymerase acidic (PA) protein had individual and synergistic effects on the polymerase activity and viral replication capacity in vitro, as well as the viral pathogenicity in mice. Furthermore, we revealed that amino acid residue 100 in PA influenced the transcription of viral RNA (vRNA) by altering the endonuclease activity, and amino acid residue 122 affected the synthesis of complementary RNA and messenger RNA by altering the RNA-binding ability and endonuclease activity of the PA protein. Taken together, we identified that two naturally occurring amino acid mutations in PA derived from H1N1/2009 virus are crucial determinants of the virulence of rEA H1N1 viruses and revealed the differential mechanism by which these two mutations affect the transcription and replication of vRNA. These findings will extend our understanding of the roles of PA in the virulence of influenza A viruses.IMPORTANCEMultiple genetic determinants are involved in the virulence of influenza A viruses. In this study, we identified two naturally occurring amino acid mutations, located at residues 100 and 122 in the polymerase acidic (PA) protein, which are associated with viral polymerase activity, replication competence, and pathogenicity in mice. In particular, we clarified the specific mechanism by which the two residues play an important role in viral transcription and replication. These findings will help to improve understanding the functions of amino acid residues in the N-terminal region of the PA protein involved in the pathogenicity of influenza A viruses.

SIRT1 silencing promotes EMT and Crizotinib resistance by regulating autophagy through AMPK/mTOR/S6K signaling pathway in EML4-ALK L1196M and EML4-ALK G1202R mutant non-small cell lung cancer cells.

Most EML4-ALK rearrangement non-small cell lung cancer (NSCLC) patients inevitably develop acquired drug resistance after treatment. The main mechanism of drug resistance is the acquired secondary mutation of ALK kinase domain. L1196M and G1202R are classical mutation sites. We urgently need to understand the underlying molecular mechanism of drug resistance to study the therapeutic targets of mutant drug-resistant NSCLC cells. The silent information regulator sirtuin1 (SIRT1) can regulate the normal energy metabolism of cells, but its role in cancer is still unclear. In our report, it was found that the SIRT1 in EML4-ALK G1202R and EML4-ALK L1196M mutant drug-resistant cells was downregulated compared with EML4-ALK NSCLC cells. The high expression of SIRT1 was related to the longer survival time of patients with lung cancer. Activation of SIRT1 induced autophagy and suppressed the invasion and migration of mutant cells. Further experiments indicated that the activation of SIRT1 inhibited the phosphorylation level of mTOR and S6K by upregulating the expression of AMPK, thus activating autophagy. SIRT1 can significantly enhanced the sensitivity of mutant cells to crizotinib, improved its ability to promote apoptosis of mutant cells, and inhibited cell proliferation. In conclusion, SIRT1 is a key regulator of drug resistant in EML4-ALK L1196M and G1202R mutant cells. SIRT1 may be a novel therapeutic target for EML4-ALK drug resistant NSCLC.

Current knowledge on the epidemiology and prevention of Avian leukosis virus in China.

Avian leukosis virus (ALV) is an enveloped retrovirus with a single-stranded RNA genome, belonging to the genus Alpharetrovirus within the family Retroviridae. The disease (Avian leukosis, AL) caused by ALV is mainly characterized by tumor development and immunosuppression in chickens, which increases susceptibility to other pathogens and leads to significant economic losses in the Chinese poultry industry. The government and poultry industry have made lots of efforts to eradicate ALV, but the threat of which remains not vanished. This review provides a summary of the updated understanding of ALV in China, which mainly focuses on genetic and molecular biology, epidemiology, and diagnostic methods. Additionally, promising antiviral agents and ALV eradication strategies performed in China are also included.