Epigenetic marks or not? The discovery of novel DNA modifications in eukaryotes.

DNA modifications add another layer of complexity to the eukaryotic genome to regulate gene expression, playing critical roles as epigenetic marks. In eukaryotes, the study of DNA epigenetic modifications has been confined to 5mC and its derivatives for decades. However, rapid developing approaches have witnessed the expansion of DNA modification reservoirs during the past several years, including the identification of 6mA, 5gmC, 4mC, and 4acC in diverse organisms. However, whether these DNA modifications function as epigenetic marks requires careful consideration. In this review, we try to present a panorama of all the DNA epigenetic modifications in eukaryotes, emphasizing recent breakthroughs in the identification of novel DNA modifications. The characterization of their roles in transcriptional regulation as potential epigenetic marks is summarized. More importantly, the pathways for generating or eliminating these DNA modifications, as well as the proteins involved are comprehensively dissected. Furthermore, we briefly discuss the potential challenges and perspectives, which should be taken into account while investigating novel DNA modifications.

NAD+ supplementation reduces neuroinflammation and cell senescence in a transgenic mouse model of Alzheimer's disease via cGAS-STING.

Alzheimer's disease (AD) is a progressive and fatal neurodegenerative disorder. Impaired neuronal bioenergetics and neuroinflammation are thought to play key roles in the progression of AD, but their interplay is not clear. Nicotinamide adenine dinucleotide (NAD+) is an important metabolite in all human cells in which it is pivotal for multiple processes including DNA repair and mitophagy, both of which are impaired in AD neurons. Here, we report that levels of NAD+ are reduced and markers of inflammation increased in the brains of APP/PS1 mutant transgenic mice with beta-amyloid pathology. Treatment of APP/PS1 mutant mice with the NAD+ precursor nicotinamide riboside (NR) for 5 mo increased brain NAD+ levels, reduced expression of proinflammatory cytokines, and decreased activation of microglia and astrocytes. NR treatment also reduced NLRP3 inflammasome expression, DNA damage, apoptosis, and cellular senescence in the AD mouse brains. Activation of cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) are associated with DNA damage and senescence. cGAS-STING elevation was observed in the AD mice and normalized by NR treatment. Cell culture experiments using microglia suggested that the beneficial effects of NR are, in part, through a cGAS-STING-dependent pathway. Levels of ectopic (cytoplasmic) DNA were increased in APP/PS1 mutant mice and human AD fibroblasts and down-regulated by NR. NR treatment induced mitophagy and improved cognitive and synaptic functions in APP/PS1 mutant mice. Our findings suggest a role for NAD+ depletion-mediated activation of cGAS-STING in neuroinflammation and cellular senescence in AD.

Urolithin A improves Alzheimer's disease cognition and restores mitophagy and lysosomal functions.

BACKGROUND: Compromised autophagy, including impaired mitophagy and lysosomal function, plays pivotal roles in Alzheimer's disease (AD). Urolithin A (UA) is a gut microbial metabolite of ellagic acid that stimulates mitophagy. The effects of UA's long-term treatment of AD and mechanisms of action are unknown. METHODS: We addressed these questions in three mouse models of AD with behavioral, electrophysiological, biochemical, and bioinformatic approaches. RESULTS: Long-term UA treatment significantly improved learning, memory, and olfactory function in different AD transgenic mice. UA also reduced amyloid beta (Aß) and tau pathologies and enhanced long-term potentiation. UA induced mitophagy via increasing lysosomal functions. UA improved cellular lysosomal function and normalized lysosomal cathepsins, primarily cathepsin Z, to restore lysosomal function in AD, indicating the critical role of cathepsins in UA-induced therapeutic effects on AD. CONCLUSIONS: Our study highlights the importance of lysosomal dysfunction in AD etiology and points to the high translational potential of UA. HIGHLIGHTS: Long-term urolithin A (UA) treatment improved learning, memory, and olfactory function in Alzheimer's disease (AD) mice. UA restored lysosomal functions in part by regulating cathepsin Z (Ctsz) protein. UA modulates immune responses and AD-specific pathophysiological pathways.

RecQ dysfunction contributes to social and depressive-like behavior and affects aldolase activity in mice.

RecQ helicase family proteins play vital roles in maintaining genome stability, including DNA replication, recombination, and DNA repair. In human cells, there are five RecQ helicases: RECQL1, Bloom syndrome (BLM), Werner syndrome (WRN), RECQL4, and RECQL5. Dysfunction or absence of RecQ proteins is associated with genetic disorders, tumorigenesis, premature aging, and neurodegeneration. The biochemical and biological roles of RecQ helicases are rather well established, however, there is no systematic study comparing the behavioral changes among various RecQ-deficient mice including consequences of exposure to DNA damage. Here, we investigated the effects of ionizing irradiation (IR) on three RecQ-deficient mouse models (RecQ1, WRN and RecQ4). We find abnormal cognitive behavior in RecQ-deficient mice in the absence of IR. Interestingly, RecQ dysfunction impairs social ability and induces depressive-like behavior in mice after a single exposure to IR, suggesting that RecQ proteins play roles in mood and cognition behavior. Further, transcriptomic and metabolomic analyses revealed significant alterations in RecQ-deficient mice, especially after IR exposure. In particular, pathways related to neuronal and microglial functions, DNA damage repair, cell cycle, and reactive oxygen responses were downregulated in the RecQ4 and WRN mice. In addition, increased DNA damage responses were found in RecQ-deficient mice. Notably, two genes, Aldolase Fructose-Bisphosphate B (Aldob) and NADPH Oxidase 4 (Nox4), were differentially expressed in RecQ-deficient mice. Our findings suggest that RecQ dysfunction contributes to social and depressive-like behaviors in mice, and that aldolase activity may be associated with these changes, representing a potential therapeutic target.

TGFßR-1/ALK5 inhibitor RepSox induces enteric glia-to-neuron transition and influences gastrointestinal mobility in adult mice.

Promoting adult neurogenesis in the enteric nervous system (ENS) may be a potential therapeutic approach to cure enteric neuropathies. Enteric glial cells (EGCs) are the most abundant glial cells in the ENS. Accumulating evidence suggests that EGCs can be a complementary source to supply new neurons during adult neurogenesis in the ENS. In the brain, astrocytes have been intensively studied for their neuronal conversion properties, and small molecules have been successfully used to induce the astrocyte-to-neuron transition. However, research on glia-to-neuron conversion in the ENS is still lacking. In this study, we used GFAP-Cre:Rosa-tdTomato mice to trace glia-to-neuron transdifferentiation in the ENS in vivo and in vitro. We showed that GFAP promoter-driven tdTomato exclusively labelled EGCs and was a suitable marker to trace EGCs and their progeny cells in the ENS of adult mice. Interestingly, we discovered that RepSox or other ALK5 inhibitors alone induced efficient transdifferentiation of EGCs into neurons in vitro. Knockdown of ALK5 further confirmed that the TGFßR-1/ALK5 signalling pathway played an essential role in the transition of EGCs to neurons. RepSox-induced neurons were Calbindin- and nNOS-positive and displayed typical neuronal electrophysiological properties. Finally, we showed that administration of RepSox (3, 10 mg· kg-1 ·d-1, i.g.) for 2 weeks significantly promoted the conversion of EGCs to neurons in the ENS and influenced gastrointestinal motility in adult mice. This study provides a method for efficiently converting adult mouse EGCs into neurons by small-molecule compounds, which might be a promising therapeutic strategy for gastrointestinal neuropathy.

Robust Sparse Bayesian Two-Dimensional Direction-of-Arrival Estimation with Gain-Phase Errors.

To reduce the influence of gain-phase errors and improve the performance of direction-of-arrival (DOA) estimation, a robust sparse Bayesian two-dimensional (2D) DOA estimation method with gain-phase errors is proposed for L-shaped sensor arrays. The proposed method introduces an auxiliary angle to transform the 2D DOA estimation problem into two 1D angle estimation problems. A sparse representation model with gain-phase errors is constructed using the diagonal element vector of the cross-correlation covariance matrix of two submatrices of the L-shaped sensor array. The expectation maximization algorithm derives unknown parameter expression, which is used for iterative operations to obtain off-grid and signal precision. Using these parameters, a new spatial spectral function is constructed to estimate the auxiliary angle. The obtained auxiliary angle is substituted into a sparse representation model with gain and phase errors, and then the sparse Bayesian learning method is used to estimate the elevation angle of the incident signal. Finally, according to the relationship of the three angles, the azimuth angle can be estimated. The simulation results show that the proposed method can effectively realize the automatic matching of the azimuth and elevation angles of the incident signal, and improves the accuracy of DOA estimation and angular resolution.

NAD+ supplementation normalizes key Alzheimer's features and DNA damage responses in a new AD mouse model with introduced DNA repair deficiency.

Emerging findings suggest that compromised cellular bioenergetics and DNA repair contribute to the pathogenesis of Alzheimer's disease (AD), but their role in disease-defining pathology is unclear. We developed a DNA repair-deficient 3xTgAD/Polß+/- mouse that exacerbates major features of human AD including phosphorylated Tau (pTau) pathologies, synaptic dysfunction, neuronal death, and cognitive impairment. Here we report that 3xTgAD/Polß+/- mice have a reduced cerebral NAD+/NADH ratio indicating impaired cerebral energy metabolism, which is normalized by nicotinamide riboside (NR) treatment. NR lessened pTau pathology in both 3xTgAD and 3xTgAD/Polß+/- mice but had no impact on amyloid ß peptide (Aß) accumulation. NR-treated 3xTgAD/Polß+/- mice exhibited reduced DNA damage, neuroinflammation, and apoptosis of hippocampal neurons and increased activity of SIRT3 in the brain. NR improved cognitive function in multiple behavioral tests and restored hippocampal synaptic plasticity in 3xTgAD mice and 3xTgAD/Polß+/- mice. In general, the deficits between genotypes and the benefits of NR were greater in 3xTgAD/Polß+/- mice than in 3xTgAD mice. Our findings suggest a pivotal role for cellular NAD+ depletion upstream of neuroinflammation, pTau, DNA damage, synaptic dysfunction, and neuronal degeneration in AD. Interventions that bolster neuronal NAD+ levels therefore have therapeutic potential for AD.

Roles of NAD+ in Health and Aging.

NAD+, the essential metabolite involved in multiple reactions such as the regulation of cellular metabolism, energy production, DNA repair, mitophagy and autophagy, inflammation, and neuronal function, has been the subject of intense research in the field of aging and disease over the last decade. NAD+ levels decline with aging and in some age-related diseases, and reduction in NAD+ affects all the hallmarks of aging. Here, we present an overview of the discovery of NAD+, the cellular pathways of producing and consuming NAD+, and discuss how imbalances in the production rate and cellular request of NAD+ likely contribute to aging and age-related diseases including neurodegeneration. Preclinical studies have revealed great potential for NAD+ precursors in promotion of healthy aging and improvement of neurodegeneration. This has led to the initiation of several clinical trials with NAD+ precursors to treat accelerated aging, age-associated dysfunctions, and diseases including Alzheimer's and Parkinson's. NAD supplementation has great future potential clinically, and these studies will also provide insight into the mechanisms of aging.

Alzheimer's Amyloid-ß Accelerates Cell Senescence and Suppresses SIRT1 in Human Neural Stem Cells.

As a lifelong source of neurons, neural stem cells (NSCs) serve multiple crucial functions in the brain. The senescence of NSCs may be associated with the onset and progression of Alzheimer's disease (AD). Our study reveals a noteworthy finding, indicating that the AD-associated pathogenic protein amyloid-ß (Aß) substantially enhances senescence-related characteristics of human NSCs. These characteristics encompass the enhanced expression of p16 and p21, the upregulation of genes associated with the senescence-associated secretory phenotype (SASP), increased SA-ß-gal activity, and the activation of the DNA damage response. Further studies revealed that Aß treatment significantly downregulates the SIRT1 protein which plays a crucial role in regulating the aging process and decreases downstream PGC-1α and FOXO3. Subsequently, we found that SIRT1 overexpression significantly alleviates a range of Aß-induced senescent markers in human NSCs. Taken together, our results uncover that Aß accelerates cellular senescence in human NSCs, making SIRT1 a highly promising therapeutic target for senescent NSCs which may contribute to age-related neurodegenerative diseases, including AD.

Mechanisms of Peitu Yimu acupuncture in repairing intestinal mucosal barrier by regulating CRF/CRFR1 pathway in diarrhea-predominant irritable bowel syndrome rats. / 培土抑木针法调节CRF/CRFR1é€šè·¯ä¿®å¤è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ è‚ é»è†œå±éšœçš„æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To investigate the effect of Peitu Yimu(strengthening spleen and soothing liver) acupuncture on intestinal mucosal barrier function and corticotropin-releasing factor (CRF)/CRF receptor 1 (CRFR1) pathway in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), so as to explore its underlying mechanism in alleviating IBS-D. METHODS: Forty female SD rats were randomly divided into blank, model, electroacupuncture (EA), and agonist groups, with 10 rats in each group. Except for the blank group, rats in the other groups were given folium sennae infusion by gavage combined with chronic unpredictable mild stress to establish IBS-D model. Rats in the EA group received acupuncture at "Tianshu"(ST25) and EA at "Zusanli"(ST36) and "Taichong"(LR3) (2 Hz/15 Hz) on one side for 20 min, with the side chosen alternately every other day, for 14 days after modeling. Rats in the agonist group received acupuncture 30 min after intravenous injection of CRFR1 agonist urocortin, with the same manipulation method and time as the EA group. Before and after intervention, visceral pain threshold and stool Bristol scores were measured. Elevated plus maze test and open field test were used to detect anxiety and depression like behavior of rats. ELISA was used to detect the contents of CRF and CRFR1 in rats serum. Immunohistochemistry was used to detect the positive expressions of CRF, CRFR1, zonula occludens protein 1(ZO-1), occlusal protein(Occludin), and closure protein 1 (Claudin-1) in colon tissue. RESULTS: Compared with the blank group, the visceral pain threshold, open arm time percentage (OT%), total distance of movement in the open field test, and positive expression of ZO-1, Occludin, and Claudin-1 in colon were decreased (P<0.01, P<0.05), while Bristol stool scores, serum CRF and CRFR1 contents, and positive expressions of CRF and CRFR1 in colon were increased (P<0.01) in the model group. After intervention and compared with the model group, the visceral pain threshold, OT%, total distance of movement in the open field test, and positive expressions of ZO-1, Occludin, and Claudin-1 in colon were increased (P<0.05, P<0.01), while Bristol stool scores, serum CRF and CRFR1 contents, and positive expressions of CRF and CRFR1 in colon were decreased (P<0.01) in the EA group；the Bristol stool scores, serum CRF content, and CRF positive expression in colon were significantly decreased in the agonist group (P<0.01). CONCLUSIONS: Peitu Yimu acupuncture can significantly improve visceral hypersensitivity and anxiety-depression state in IBS-D rats. Its mechanism may be related to the inhibition of CRF/CRFR1 pathway and restoration of intestinal tight junction protein expressions.

SMRT sequencing of a full-length transcriptome reveals cold induced alternative splicing in Vitis amurensis root.

Alternative splicing enhances diversity at the transcriptional and protein levels that widely involved in plant response to biotic and abiotic stresses. V. amurensis is an extremely cold-tolerant wild grape variety, however, studies on alternative splicing (AS) in amur grape at low temperatures are currently poorly understood. In this study, we analyzed full-length transcriptome and RNA seq data at 0, 2, and 24 h after cold stress in V. amurensis roots. Following quality control and correction, 221,170 high-quality full-length non-concatemer (FLNC) reads were identified. A total of 16,181 loci and 30,733 isoforms were identified. These included 22,868 novel isoforms from annotated genes and 2815 isoforms from 2389 novel genes. Among the distinguished novel isoforms, 673 Long non-coding RNAs (LncRNAs) and 18,164 novel isoforms open reading frame (ORF) region were found. A total of 2958 genes produced 8797 AS events, of which 189 genes were involved in the low-temperature response. Twelve transcription factors show AS during cold treatment and VaMYB108 was selected for initial exploration. Two transcripts, Chr05.63.1 (VaMYB108short) and Chr05.63.2 (VaMYB108normal) of VaMYB108, display up-regulated expression after cold treatment in amur grape roots and are both localized in the nucleus. Only VaMYB108normal exhibits transcriptional activation activity. Overexpression of either VaMYB108short or VaMYB108normal in grape roots leads to increased expression of the other transcript and both increased chilling resistance of amur grape roots. The results improve and supplement the genome annotations and provide insights for further investigation into AS mechanisms during cold stress in V. amurensis.

The Cissus quadrangularis genome reveals its adaptive features in an arid habitat.

Cissus quadrangularis is a tetraploid species belonging to the Vitaceae family and is known for the Crassulacean acid metabolism (CAM) pathway in the succulent stem, while the leaves perform C3 photosynthesis. Here, we report a high-quality genome of C. quadrangularis comprising a total size of 679.2 Mb which was phased into two subgenomes. Genome annotation identified 51 857 protein-coding genes, while approximately 47.75% of the genome was composed of repetitive sequences. Gene expression ratios of two subgenomes demonstrated that the sub-A genome as the dominant subgenome played a vital role during the drought tolerance. Genome divergence analysis suggests that the tetraploidization event occurred around 8.9 million years ago. Transcriptome data revealed that pathways related to cutin, suberine, and wax metabolism were enriched in the stem during drought treatment, suggesting that these genes contributed to the drought adaption. Additionally, a subset of CAM-related genes displayed diurnal expression patterns in the succulent stems but not in leaves, indicating that stem-biased expression of existing genes contributed to the CAM evolution. Our findings provide insights into the mechanisms of drought adaptation and photosynthesis transition in plants.

[Study on the mechanism of electroacupuncture repairing intestinal barrier via regulating mast cell in rats with diarrhea-predominant irritable bowel syndrome].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on mast cell activation-related substances and intestinal barrier function in diarrhea-predominant irritable bowel syndrome (IBS-D) model rats, so as to explore its underlying mechanisms. METHODS: Thirty female SD rats were randomly divided into control group, model group and EA group, with 10 rats in each group. IBS-D model was established by chronic unpredictable mild stress combined with senna solution gavage. Rats in the EA group received EA treatment (2 Hz/15 Hz，0.1-1.0 mA) at "Zusanli" (ST36), "Taichong"(LR3) and "Tianshu"(ST25), 20 min per day, for a total of 14 days, with sides alternated daily. Visceral pain threshold was used to evaluate visceral hypersensitivity, diarrhea index was used to evaluate diarrhea degree. After all treatments, the pathological scores of colon were recorded after HE staining, the contents of cholecystokinin (CCK), substance P (SP), tryptase (TPS) and adenosine triphosphate (ATP) in colon were detected by ELISA, and the expressions of colonic tight junction protein ZO-1 and occludin were detected by Western blot. RESULTS: Compared with the control group, the visceral pain threshold, the expression levels of colonic ZO-1 and occludin proteins decreased (P<0.01), while the diarrhea index, the contents of colonic CCK, SP, TPS and ATP were significantly increased (P<0.01) in the model group. After intervention, in comparison with the model group, the visceral pain thre-shold, the protein expression levels of colonic ZO-1 and occludin protein increased (P<0.01), while the diarrhea index, the contents of colonic CCK, SP, TPS and ATP were significantly decreased (P<0.01) in the EA group. CONCLUSION: EA can significantly alleviate the symptoms of visceral hypersensitivity and diarrhea in IBS-D rats. Its mechanism may be related to down-regulating colonic CCK, SP, TPS and ATP, inhibiting mast cell activation and degranulation, and up-regulating colonic barrier tight junction proteins.

Dissecting the effect of ethylene in the transcriptional regulation of chilling treatment in grapevine leaves.

Ethylene (ETH) plays important roles in various development programs and stress responses in plants. In grapevines, ETH increased dramatically under chilling stress and is known to positively regulate cold tolerance. However, the role of ETH in transcriptional regulation during chilling stress of grapevine leaves is still not clear. To address this gap, targeted hormone profiling and transcriptomic analysis were performed on leaves of Vitis amurensis under chilling stress with and without aminoethoxyvinylglycine (AVG, a inhibitor of ETH synthesis) treatment. APETALA2/ETHYLENE RESPONSIVE FACTOR (AP2/ERF) and WRKY transcription factors (TF) were only the two highly enriched TF families that were consistently up-regulated during chilling stress but inhibited by AVG. The comparison of leaf transcriptomes between chilling treatment and chilling with AVG allowed the identification of potential ETH-regulated genes. Potential genes that are positively regulated by ETH are enriched in solute transport, protein biosynthesis, phytohormone action, antioxidant and carbohydrate metabolism. Conversely, genes related to the synthesis and signaling of ETH, indole-3-acetic acid (IAA), abscisic acid (ABA) were up-regulated by chilling treatment but inhibited by AVG. The contents of ETH, ABA and IAA also paralleled with the transcriptome data, which suggests that the response of ABA and IAA during chilling stress may regulate by ETH signaling, and together may belong to an integrated network of hormonal signaling pathways underpinning chilling stress response in grapevine leaves. Together, these findings provide new clues for further studying the complex regulatory mechanism of ETH under low-temperature stress in plants more generally and new opportunities for breeding cold-resilient grapevines.

Acupuncture as an adjunctive therapy for gastric ulcer: A modified Delphi consensus study.

BACKGROUND: Acupuncture is often used as an adjunctive therapy for gastric ulcer (GU). However, there is still a lack of evidence on the appropriate and optimal interventions for acupuncture. This study aimed to optimize the acupuncture treatment of gastric ulcers based on expert consensus for guiding acupuncturists in clinical practice. METHODS: To conduct this study, research evidence was gathered from databases in both Chinese and English. After discussion, preliminary clinical questions were developed. Following three rounds of multidisciplinary clinical expert consultation, the initial consensus questionnaire was formed after testing and modification by team members. A Delphi consensus was ultimately reached to answer the questionnaire and develop guidance for acupuncture treatment. A 9-point Likert-type scale was used to measure the agreement of expert consensus, where a score of 80% between 7 and 9 was defined as "agreement." RESULTS: After two rounds of Delphi voting, a total of 35 items reached an agreement. These items can be roughly divided into 6 domains. According to expert consensus, the application of acupuncture for gastric ulcer should follow a semistandardized approach. Based on the syndrome differentiation, the main acupoints recommended are Zusanli (ST36), Zhongwan (CV12), Neiguan (PC6), and Sanyinjiao (SP6), while the adjunct acupoints include Taichong (LR3), Guanyuan (CV4), Xuehai (SP10), and Taixi (KI3). In the experience of experts, adverse events associated with acupuncture are typically mild and often manifest as subcutaneous hematomas. CONCLUSION: There is a lack of definitive acupuncture guidelines that can effectively determine the optimal therapeutic approach for the treatment of gastric ulcer. This expert consensus provides recommendations for clinical research and practice of acupuncture, with a particular focus on the selection of acupoints. However, further exploration through rigorous studies is necessary due to the limited availability of clinical evidence.

Effects of acupuncture on gut microbiota and short-chain fatty acids in patients with functional constipation: a randomized placebo-controlled trial.

Objective: To comprehensively evaluate the effect of acupuncture on gut microbiota, identify specific microbes closely related to the clinical efficacy of acupuncture, and explored the role of short-chain fatty acids (SCFAs). Methods: A randomized placebo-controlled trial was conducted with 80 FC patients and 28 healthy controls (HCs). FC patients randomly received 16 acupuncture (n = 40) or sham acupuncture (n = 40) sessions over 4 weeks; HCs received no treatment. The change in the proportion of patients with mean weekly complete spontaneous bowel movements (CSBMs) was considered as the primary outcome measure. Moreover, the composition and the predictive metabolic function of the gut microbiota from feceal samples were analyzed by 16S rRNA gene sequencing, while feceal SCFAs were identified via gas chromatography-mass spectrometry (GC-MS). Results: Compared to sham acupuncture, acupuncture significantly increased the proportion of CSBM responders, and improved spontaneous bowel movements (SBMs), straining, stool consistency, and quality of life. Moreover, Sequencing of 16S rRNA genes revealed that acupuncture improved ß-diversity and restored the composition of gut microbiota. Specifically, the abundance of beneficial bacteria such as g_Lactobacillus increased while that of pathogenic bacteria such as g_Pseudomonas decreased after acupuncture, which were significantly correlated with alleviated symptoms. Moreover, ten microbes including g_Coprobacter, g_Lactobacillus, and g_Eubacterium_coprostanoligenes_group might be considered acupuncture-specific microbes, and formed a stable interaction network. Additionally, GC-MS analysis indicated that acupuncture increased the content of butyrate acid in the gut, which was positively correlated with an increase in defecation frequency and a decrease in acupuncture-related pathogens. Finally, acupuncture specific-microbes including g_Coprobacter, g_Lactobacillus, g_Pseudomonas, g_Eubacterium_coprostanoligenes_group, g_Erysipelotrichaceae_UCG.003, g_Prevotellaceae_UCG.001, and g_Rolstonia could accurately predict the clinical efficacy of acupuncture (AUC = 0.918). Conclusion: Acupuncture could effectively improve clinical symptoms in FC patients, and was associated with gut microbiota reshaping and increased butyrate acid levels. Moreover, key microbial genera such as g_Coprobacter and g_Lactobacillus was predictive of acupuncture efficacy in treating FC. Future studies are required to validate the causal relationship between key microbial genera and acupuncture clinical efficacy, and should explore further metabolic pathways for designing personalized treatment strategies. Clinical Trial Registration: http://www.chictr.org.cn, Identifier: ChiCTR2100048831.

Alzheimer's Amyloid-ß Accelerates Human Neuronal Cell Senescence Which Could Be Rescued by Sirtuin-1 and Aspirin.

Cellular senescence is a major biological process related to aging. Neuronal cell senescence contributes to the pathogenesis of many aging-related neurodegenerative diseases including Alzheimer's disease (AD). In this study, we showed that amyloid-ß42 oligomers (Aß), one of the core pathological players of AD, significantly upregulated the expression of senescence markers, p21, plasminogen activator inhibitor-1 (PAI-1), and SA-ß-gal (senescence-associated ß-galactosidase) in multiple human neuronal cells, including SK-N-SH cells, SH-SY5Y cells, and neural stem cell (NSC)-derived neuronal cells. Moreover, it was consistently observed among the cells that Aß promoted senescence-associated DNA damage as the levels of 8-OHdG staining, histone variant H2AX phosphorylation (γ-H2AX), and genomic DNA lesion increased. Mechanism study revealed that the exposure of Aß markedly suppressed the expression of sirtuin-1 (SIRT1), a critical regulator of aging, and the exogenous expression of SIRT1 alleviated Aß-induced cell senescence phenotypes. To our surprise, a widely used cardiovascular drug aspirin considerably rescued Aß-induced cellular senescence at least partially through its regulation of SIRT1. In conclusion, our findings clearly demonstrate that exposure of Aß alone is sufficient to accelerate the senescence of human neuronal cells through the downregulation of SIRT1.

Alzheimer's Amyloid-ß Accelerates Cell Senescence and Suppresses the SIRT1/NRF2 Pathway in Human Microglial Cells.

Microglia play important roles in maintenance of brain homeostasis, while due to some pathological stimuli in aging-related neurodegenerative diseases including Alzheimer's disease, they are malfunctioning. Here, we demonstrated that amyloid-ß (Aß) accelerated cell senescence characterized by the upregulation of p21 and PAI-1 as well as senescence-associated beta-galactosidase (SA-ß-gal) in human microglial cells. Consistently, Aß induced the senescence-associated mitochondrial dysfunctions such as repression of ATP production, oxygen consumption rate (OCR), and mitochondrial membrane potential and enhancement of ROS production. Furthermore, Aß was found to significantly suppress mRNA expression and protein level of Sirtuin-1 (SIRT1), a key regulator of senescence, and inhibit mRNA expression and translocation of NRF2, a critical transcription factor in inflammatory responses, leading to impairment of phagocytosis. Rescue of SIRT1, as expected, could counteract the pathological effects of Aß. In summary, our findings revealed that Aß accelerates human microglial senescence mainly through its suppression of the SIRT1/NRF2 pathway and suggested that genetic and pharmaceutical rescue of SIRT1 may provide a potential alternative treatment.

Maintenance of Intestinal Homeostasis in Diarrhea-Predominant Irritable Bowel Syndrome by Electroacupuncture Through Submucosal Enteric Glial Cell-Derived S-Nitrosoglutathione.

Objective: To determine whether electroacupuncture (EA) maintains intestinal homeostasis in diarrhea-predominant irritable bowel syndrome (IBS-D) rats by repairing intestinal barrier function through enteric glial cell (EGC)-derived S-nitrosoglutathione (GSNO). Methods: Sprague-Dawley rats were randomly divided into a control group (n = 10) and an IBS-D group (n = 20). These rats received senna solution by gavage and chronic unpredictable mild stress for 14 days and were further divided into a model group (n = 10) and an EA group (n = 10). Rats in the EA group were electroacupunctured at ST25 (Tianshu), ST36 (Zusanli), and LR3 (Taichong) for 20 min every day for 14 days. The abdominal withdrawal reflex (AWR), the percentage of time spent in open arms (OT%) in the elevated plus maze test, and the diarrhea index (DI) were measured. Histopathological examination was performed to evaluate the pathological features of the colon after sacrificing the rats. Transmission electron microscopy was used to observe the EGC in the muscle and submucosal layers. Enzyme-linked immunosorbent assay was performed to detect GSNO expression in the colon. Double immunofluorescence labeling was used to detect the colocalized GFAP and GSNO expressions in the muscle and submucosal layers. Plasma FITC-dextran was used to measure intestinal permeability, whereas western blot was used to detect ZO-1 and occludin expressions in the colon. Results: OT% and ZO-1 and occludin expressions were significantly lower than those of the control group, whereas AWR scores, DI, GSNO expression in the colon, colocalized GFAP and GSNO expressions in the submucosal layer, and intestinal permeability were significantly higher than those of the control group. Structural EGC abnormalities were observed in the model group. After EA treatment, OT% and ZO-1 and occludin expressions increased significantly, whereas AWR scores, DI, GSNO expression, colocalized GFAP and GSNO expressions in the submucosal layer, and intestinal permeability decreased significantly. The EGC structure was then restored to its normal state. Conclusion: EA treatment downregulates the submucosal EGC-derived GSNO expressions, repairs the intestinal barrier by upregulating the ZO-1 and occludin expression, and improves IBS-D symptoms, including visceral hypersensitivity, anxiety, and diarrhea, suggesting a potential role for EGC-derived GSNO in the regulation of intestinal homeostasis in IBS-D rats.

Comparison of vegetable production, resource-use efficiency and environmental performance of high-technology and conventional farming systems for urban agriculture in the tropical city of Singapore.

Urban farming can improve cities' food security and resilience, but the performance of different farming systems with respect to land and investment constraints has not been systematically investigated. Here, we compared conventional soil-based farming, vertical farming with natural lighting (Vnat), and indoor vertical farming. This study aimed to compare (1) the dynamic production of leafy vegetables over time given the same amount of investment and land constraints, (2) the associated water and energy use, and (3) the global warming potential (GWP) of the urban farming sector if each of the three farming systems was solely used in the tropical city-state of Singapore. A system dynamics (SD) model was constructed to map the potential quantity of leafy vegetables produced, together with the water and energy use of each farming system. The land and monetary investment constraints were set at an additional 0.3% of the total land area of Singapore and an annual investment of SGD 10-20 million (0.001-0.005% of Singapore's annual GDP). Vnat farming was predicted to have the highest production level (110,000 t) and self-sufficiency (76.9% of total demand) by 2050 based on the SD model. This would be >3 times the self-sufficiency level achieved by indoor and soil-based farming systems given the same investment and land constraints. Indoor farming was simulated to use <14% the land area of Vnat while soil-based farming exhausted the additional 0.3% of the land allocated. Indoor farming was also the most energy intensive system, requiring 100 times more than Vnat farming. Comparison of the GHG emission rates showed that indoor farming had the greatest GWP-at 2.51 kg CO2-eq per kg of lettuce produced. Our results suggest that Vnat farming may be the best form of urban farming system to provide large amounts of food in Singapore, considering the production level, the amount of resources used, and the environmental impacts.