The metabolite alpha-ketobutyrate extends lifespan by promoting peroxisomal function in C. elegans

Comparative secretome and proteome analysis unveils the response mechanism in the phosphorus utilization of Alexandrium pacificum

Phosphorus (P) acts as a crucial limiting nutrient for the growth of marine phytoplankton cells and the formation of algal blooms. The dinoflagellate Alexandrium pacificum is known for causing frequent and intense blooms in specific estuarine and coastal regions. In this study, we investigated the growth and physiological transformations under conditions characterized by P-deficiency, NaH2PO4, and ATP. For the first time, an integrated comparative analysis of the secretome and proteome was performed to investigate the global protein expression profile of A. pacificum, with 355 and 2308 differentially expressed proteins (DEPs), respectively. The results demonstrated that P-deficiency led to a reduction in growth and notable decreases in metabolic processes in A. pacificum. In P-deficient and ATP groups, the expression of secretory protein alkaline phosphatase A (PhoA) was increased, while intracellular acid phosphatase (ACP) displayed significant upregulation in P-deficient group, indicating that A. pacificum has evolved multiple organic P utilization strategies to adapt to low-P environments. A. pacificum can utilize the intracellular carbohydrate storage pools via glycolysis and the TCA cycle to replenish Calvin cycle intermediates. However, the growth of the ATP and NaH2PO4 groups showed no significant alteration. These results suggest that A. pacificum possesses distinct adaptive strategies towards P-deficiency in the environment and employs specific mechanisms for utilizing organic P, which may be a crucial factor in the formation of blooms in low inorganic P environments.

Association of the gut microbiome with diabetic nephropathy and the mediated effect of metabolites: friend or enemy?

OBJECTIVE

The effects of gut microbiome and its metabolites on diabetic nephropathy (DN) have been inadequately elucidated. The aim of this study is to assess the causal effect of gut microbiome on DN and the mediated effect of metabolites by a two-step Mendelian randomization (MR).

METHODS

Datasets of gut microbiome, metabolites, and DN were acquired in genome-wide association studies and screened for single nucleotide polymorphisms according to the underlying assumptions of MR. Subsequently, inverse variance weighted was used as the primary method for MR analysis to assess the causal effect of gut microbiome on DN and the mediated effect of metabolites. Finally, MR-Egger intercept, Cochran's Q test, and leave-one-out sensitivity analysis were used to assess the horizontal pleiotropy, heterogeneity, and robustness of the results, respectively.

RESULTS

The MR analysis demonstrated that Parabacteroides merdae increased the genetic susceptibility to DN by reducing acetylcarnitine (C2) to propionylcarnitine (C3) ratio (mediated proportion 8.95%, mediated effect 0.024) and alpha-ketobutyrate to 3-methyl-2-oxovalerate ratio (mediated proportion 19.90%, mediated effect 0.053). MR Egger showed that these results lack horizontal pleiotropy (p ≥ 0.05). Cochran's Q and sensitivity analysis suggested these results had no heterogeneity (p ≥ 0.05) and were robust.

CONCLUSION

Our findings revealed the pathway by which Parabacteroides merdae increased the genetic susceptibility to DN by regulating acetylcarnitine (C2) to propionylcarnitine (C3) ratio and alpha-ketobutyrate to 3-methyl-2-oxovalerate ratio. It provides new genetic insights for understanding the pathogenesis of DN and related drug research.

Homocysteine-Responsive Covalent Organic Frameworks as Signaling Scaffolds: Modulating Transsulfuration for Depression Treatment

Depression is a significant global health concern with limited effective treatment strategies to date. Elevated homocysteine is identified as a critical factor contributing to the severity of depression by aggravating neuroinflammation. Herein, this study develops a diverse array of homocysteine-stimulated responsive covalent organic frameworks (COFs) as novel therapeutic agents. Using Schiff-base condensation reactions between cystamine/selenocystamine and various C2- and C3-symmetric aryl aldehydes, it successfully synthesized a library of 20 COFs. The sensitivity and specificity of the resultant COFs for homocysteine clearance are validated using serum samples from patients with depression and a mouse model. Non-targeted metabolomics and transcriptomics analyses revealed that these COFs not only exogenously and directly scavenge homocysteine but also synergistically enhance the transsulfuration pathway within the endogenous metabolic cycle for efficient clearance. Furthermore, these COFs mitigated neuroinflammation by inhibiting inflammatory responses, scavenging reactive oxygen species, and modulating neuronal and microglial activity. They also activated neuroactive ligand-receptor signaling pathways and preserved mitochondrial function, thereby maintaining oxidative phosphorylation. Collectively, these mechanisms resulted in significant improvements in anxiety and depressive behaviors in mice. This study pioneers the therapeutic application of homocysteine-responsive COFs for depression treatment, opening up tremendous opportunities for the biomedical applications of COFs.

Matrine Inhibits High-Glucose-Diet-Induced Fat Accumulation and Aβ-Mediated Lipid Metabolic Disorder via AAK-2/NHR-49 Pathway in Caenorhabditis elegans

Matrine, a quinoline alkaloid, possesses lipid-regulating effects, but the underlying mechanisms are rarely characterized in vivo. With a fat-accumulating Caenorhabditis elegans model, we show that matrine reduces the fat content and the DHS-3::GFP-labeled lipid droplets in high-glucose-diet N2 and transgenic LIU1 nematodes, respectively. Based on RNA-seq, this study demonstrates that a loss of AAK-2 function suppresses the fat-lowering effects of matrine, and the hyperactivated AAK-2 strain has a relatively lower fat content than N2. The involvement of NHR-49 in matrine's fat-lowering effects further suggests that matrine impacts fat breakdown and storage via the AAK-2/NHR-49-governed pathway. Using the transgenic SJ4143 (ges-1::GFP(mit)) and VS10 (vha-6p::mRFP-PTS1), we show that matrine activates the AAK-2/NHR-49 pathway, coupling the alteration of mitochondrial and peroxisomal functions. Studies of aak-2 and nhr-49 mutants reveal that AAK-2 and NHR-49 modulate lipid metabolic homeostasis; meanwhile, matrine increases physical fitness and lifespan through activating the AAK-2/NHR-49 pathway in high-glucose-diet nematodes. Surprisingly, we found that β-amyloid (Aβ) induces lipid metabolic disorder in an Alzheimer's disease (AD) C. elegans model, but matrine not only reduces Aβ aggregation but also alleviates Aβ-mediated lipid metabolic disorder. Our data suggest that matrine has promise as a fat-lowering agent, and also offer new insights into its therapeutic potential for AD.

Ethyl-Dimer-Galactopyranoside, a New Glycoside with Attractive Activity from Cultures of Caenorhabditis elegans on NGM

The nematode Caenorhabditis elegans is an important model for the study of social behaviors. Ethyl-dimer-galactopyranoside, a new glycoside isolated from the cultures of C. elegans on nematode growth medium (NGM), exhibited strong attractive activity toward C. elegans at different doses, reaching a chemotaxis index of 0.36 at 500 pg. Moreover, the results of transcriptome and chemotaxis assays suggest that ASE neurons are involved in the attractive effect of ethyl-dimer-galactopyranoside toward C. elegans. This study supplemented the understanding of the structure and biological function of modular glycosides of C. elegans. It is noteworthy that the chemotaxis index of 500 pg of ethyl-dimer-galactopyranoside toward Meloidogyne incognita was 0.19. It will also help us to further explore the complex multidirectional communication networks among different nematode species, which may aid the development of new treatment approaches for harmful parasitic nematodes in agriculture.

Mid-life anti-inflammatory metabolites are inversely associated with long-term cardiovascular disease events

BACKGROUND

Preclinical data have shown that low levels of metabolites with anti-inflammatory properties may impact metabolic disease processes. However, the association between mid-life levels of such metabolites and long-term ASCVD risk is not known.

METHODS

We characterised the plasma metabolomic profile (1228 metabolites) of 1852 participants (58.1 ± 7.5 years old, 69.6% female, 43.6% self-identified as Black) enrolled in the Heart Strategies Concentrating on Risk Evaluation (Heart SCORE) study. Logistic regression was used to assess the impact of metabolite levels on ASCVD risk (nonfatal MI, revascularisation, and cardiac mortality). We additionally explored the effect of genetic variants neighbouring ASCVD-related genes on the levels of metabolites predictive of ASCVD events. The Atherosclerosis Risk in Communities (ARIC) study (n = 4790; 75.5 ± 5.1 years old, 57.4% female, 19.5% self-identified as Black) was used as an independent validation cohort.

FINDINGS

In fully adjusted models, alpha-ketobutyrate [AKB] (OR 0.62 [95% CI, 0.49-0.80]; p < 0.001), and 1-palmitoyl-2-linoleoyl-GPI [OR, 0.62, 95% CI, 0.47-0.83; p < 0.001], two metabolites in amino acid and phosphatidylinositol lipid pathways, respectively, showed a significant protective association with incident ASCVD risk in both Heart SCORE and ARIC cohorts. Three plasmalogens and a bilirubin derivative, whose levels were regulated by genetic variants neighbouring FADS1 and UGT1A1, respectively, exhibited a significant protective association with ASCVD risk in the Heart SCORE only.

INTERPRETATION

Higher mid-life levels of AKB and 1-palmitoyl-2-linoleoyl-GPI metabolites may be associated with lower risk late-life ASCVD events. Further research can determine the causality and therapeutic potential of these metabolites in ASCVD.

FUNDING

This study was funded by the Pennsylvania Department of Health (ME-02-384). The department specifically disclaims responsibility for any analyses, interpretations, or conclusions. Additional funding was provided by National Institutes of Health (NIH) grant R01HL089292 and UL1 TR001857 (Steven Reis). Further, NIH funded R01HL141824 and R01HL168683 were used for the ARIC study validation (Bing Yu).

Astaxanthin promotes the longevity of Caenorhabditis elegans via modulation of the intracellular redox status and PHA-4-mediated autophagy

Astaxanthin is a xanthophyll carotenoid which has been associated with a number of health-promoting effects, including anti-aging; however, the underlying mechanisms are not fully understood. In the present study, it was found that astaxanthin promoted the longevity of wild-type (N2) Caenorhabditis elegans (C. elegans). The lifespan-extending effect of astaxanthin was associated with a significant decrease of lipofuscin accumulation and the reduction of the age-related decline in spontaneous motility. Meanwhile, astaxanthin enhanced the oxidative stress resistance in C. elegans, preventing the elevation of the reactive oxygen species and alleviating juglone-induced toxicity. Further studies revealed that astaxanthin treatment induced the expression of the skn-1 gene; besides, the lifespan-extending effect of astaxanthin relied on SKN-1. Additionally, the expression of age-1, a PI3K homolog gene, and let-363, a target of the rapamycin (TOR) homolog gene, was decreased, while the expression of PHA-4, a transcription factor negatively regulated by TOR signaling, was increased by astaxanthin treatment. PHA-4 has been demonstrated to regulate the expression of genes playing critical roles in the autophagy-lysosome pathway (ALP). Consistently, several key genes related to ALP, including lgg-1, atg-5, vps-34, ncr-1 and asm-1 were upregulated in C. elegans treated with astaxanthin. Knockdown of pha-4 expression by siRNA prevented the elevation of the above ALP-related genes, while diminishing the lifespan-extension effect of astaxanthin. Overall, these results indicated that astaxanthin prolonged the lifespan of C. elegans via modulating the intracellular redox status and promoting PHA-4-mediated autophagy.

Time-restricted eating reveals a "younger" immune system and reshapes the intestinal microbiome in human

Time-restricted eating (TRE) has been shown to extent lifespans in drosophila and mouse models by affecting metabolic and anti-inflammatory activities. However, the effect of TRE on the human immune system, especially on immunosenescence, intestinal microbiome, and metabolism remains unclear. We conducted a 30-day 16:8 TRE single-arm clinical trial with 49 participants. Participants consumed daily meals from 9 a.m. to 5 p.m., provided by a nutrition canteen with a balanced, calorie-appropriate nutrition, which is designed by clinical nutritionists (ChiCTR2200058137). We monitored weight changes and weight-related parameters and focused on changes in the frequency of CD4+ senescent T cells, immune repertoire from peripheral blood, as well as serum metabolites and gut microbiota. We found that up to 95.9 % of subjects experienced sustained weight loss after TRE. The frequency of circulating senescent CD4+ T cells was decreased, while the frequency of Th1, Treg, Tfh-like, and B cells was increased. Regarding the immune repertoire, the proportions of T cell receptor alpha and beta chains were increased, whereas B cell receptor kappa and lambda chains were reduced. In addition, a reduced class switch recombination from immunoglobulin M (IgM) to immunoglobulin A (IgA) was observed. TRE upregulated the levels of anti-inflammatory and anti-aging serum metabolites named sphingosine-1-phosphate and prostaglandin-1. Additionally, several anti-inflammatory bacteria and probiotics were increased, such as Akkermansia and Rikenellaceae, and the composition of the gut microbiota tended to be "younger". Overall, TRE showed multiple anti-aging effects, which may help humans maintain a healthy lifestyle to stay "young". Clinical Trial Registration URL: https://www.chictr.org.cn/showproj.html?proj=159876.

Transgenerational response of germline histone acetyltransferases and deacetylases to nanoplastics at predicted environmental doses in Caenorhabditis elegans

Nanoplastics could cause toxic effects on organism and their offsprings; however, how this transgenerational toxicity is formed remains largely unclear. We here examined potential involvement of germline histone acetylation regulation in modulating transgenerational toxicity of polyetyrene nanoparticle (PS-NP) in Caenorhabditis elegans. At parental generation (P0-G), PS-NP (1-100 μg/L) decreased expressions of germline cbp-1 and taf-1 encoding histone acetyltransferases, as well as germline expressions of sir-2.1 and hda-3 encoding histone deacetylase. Decrease in these 4 germline genes were also observed in the offspring of PS-NP (1-100 μg/L) exposed nematodes. Germline RNAi of cbp-1, taf-1, sir-2.1 and hda-3 resulted in more severe transgenerational PS-NP toxicity on locomotion and brood size. Meanwhile, in PS-NP exposed nematodes, germline RNAi of cbp-1, taf-1, sir-2.1 and hda-3 increased expression of genes encoding insulin, FGF, Wnt, and/or Notch ligands and expressions of their receptor genes in the offspring. Susceptibility to transgenerational PS-NP toxicity in cbp-1(RNAi), taf-1(RNAi), sir-2.1(RNAi), and hda-3 (RNAi) was inhibited by RNAi of these germline ligands genes. Moreover, histone deacetylase inhibition served as molecular initiating event (MIE) leading to transgenerational toxicity in epigenetic adverse outcome pathway (AOP) for nanoplastics. Our data provided evidence that germline histone acetylation regulation functioned as an important mechanism for transgenerational toxicity of nanoplastics at predicted environmental doses (PEDs) by affecting secreted ligands in organisms.

Aronia melanocarpa extract extends the lifespan and health-span of Caenorhabditis elegans via mitogen-activated protein kinase 1

Aging is a highly complex process and one of the largest risk factors for many chronic diseases. Aronia melanocarpa (AM) is rich in bioactive phytochemicals with antioxidant, anti-inflammatory, and anticancer properties. However, little is known about its effects on aging. The objective of this study was to evaluate the effects of AM extract on lifespan and health-span using Caenorhabditis elegans as a representative model. The mechanisms of its effects were explored using transcriptomics and untargeted metabolomics. Results showed that the lifespan of C. elegans was significantly extended by 22.2% after high-dose AM treatment. AM improved the behavior and physiological functions of C. elegans by increasing the pharyngeal pumping rate, decreasing lipofuscin accumulation and the reactive oxygen species level, enhancing resistance to oxidative stress, and increasing the activities of superoxide dismutase and catalase. Transcriptome analysis showed that the pmk-1 gene (mitogen-activated protein kinase 1), which is involved in the MAPK signaling pathway, was the gene with the largest fold change after AM intervention. However, in the C. elegans pmk-1(km25) mutant, the beneficial effect of AM in improving nematode senescence disappeared. An untargeted metabolomics study showed that the levels of 4-hydroxyproline, rhamnose, and cysteine were increased after AM supplementation, and their extending effect on the lifespan and health-span of C. elegans were partly dependent on the pmk-1 gene. In conclusion, our results revealed that AM can promote the lifespan and health-span of C. elegans via the PMK-1 pathway, highlighting the potential of AM as a dietary supplement to delay aging.

Lifespan effects in male UM-HET3 mice treated with sodium thiosulfate, 16-hydroxyestriol, and late-start canagliflozin

Genetically heterogeneous UM-HET3 mice born in 2020 were used to test possible lifespan effects of alpha-ketoglutarate (AKG), 2,4-dinitrophenol (DNP), hydralazine (HYD), nebivolol (NEBI), 16α-hydroxyestriol (OH_Est), and sodium thiosulfate (THIO), and to evaluate the effects of canagliflozin (Cana) when started at 16 months of age. OH_Est produced a 15% increase (p = 0.0001) in median lifespan in males but led to a significant (7%) decline in female lifespan. Cana, started at 16 months, also led to a significant increase (14%, p = 0.004) in males and a significant decline (6%, p = 0.03) in females. Cana given to mice at 6 months led, as in our previous study, to an increase in male lifespan without any change in female lifespan, suggesting that this agent may lead to female-specific late-life harm. We found that blood levels of Cana were approximately 20-fold higher in aged females than in young males, suggesting a possible mechanism for the sex-specific disparities in its effects. NEBI was also found to produce a female-specific decline (4%, p = 0.03) in lifespan. None of the other tested drugs provided a lifespan benefit in either sex. These data bring to 7 the list of ITP-tested drugs that induce at least a 10% lifespan increase in one or both sexes, add a fourth drug with demonstrated mid-life benefits on lifespan, and provide a testable hypothesis that might explain the sexual dimorphism in lifespan effects of the SGLT2 inhibitor Cana.

Metabolic Pathways Affected in Patients Undergoing Hemodialysis and Their Relationship with Inflammation

Worldwide, 3.9 million individuals rely on kidney replacement therapy. They experience heightened susceptibility to cardiovascular diseases and mortality, alongside an increased risk of infections and malignancies, with inflammation being key to explaining this intensified risk. This study utilized semi-targeted metabolomics to explore novel metabolic pathways related to inflammation in this population. We collected pre- and post-session blood samples of patients who had already undergone one year of chronic hemodialysis and used liquid chromatography and high-resolution mass spectrometry to perform a metabolomic analysis. Afterwards, we employed both univariate (Mann-Whitney test) and multivariate (logistic regression with LASSO regularization) to identify metabolites associated with inflammation. In the univariate analysis, indole-3-acetaldehyde, 2-ketobutyric acid, and urocanic acid showed statistically significant decreases in median concentrations in the presence of inflammation. In the multivariate analysis, metabolites positively associated with inflammation included allantoin, taurodeoxycholic acid, norepinephrine, pyroglutamic acid, and L-hydroorotic acid. Conversely, metabolites showing negative associations with inflammation included benzoic acid, indole-3-acetaldehyde, methionine, citrulline, alphaketoglutarate, n-acetyl-ornithine, and 3-4-dihydroxibenzeneacetic acid. Non-inflamed patients exhibit preserved autophagy and reduced mitochondrial dysfunction. Understanding inflammation in this group hinges on the metabolism of arginine and the urea cycle. Additionally, the microbiota, particularly uricase-producing bacteria and those metabolizing tryptophan, play critical roles.

Disrupting the SKN-1 homeostat: mechanistic insights and phenotypic outcomes

The mechanisms that govern maintenance of cellular homeostasis are crucial to the lifespan and healthspan of all living systems. As an organism ages, there is a gradual decline in cellular homeostasis that leads to senescence and death. As an organism lives into advanced age, the cells within will attempt to abate age-related decline by enhancing the activity of cellular stress pathways. The regulation of cellular stress responses by transcription factors SKN-1/Nrf2 is a well characterized pathway in which cellular stress, particularly xenobiotic stress, is abated by SKN-1/Nrf2-mediated transcriptional activation of the Phase II detoxification pathway. However, SKN-1/Nrf2 also regulates a multitude of other processes including development, pathogenic stress responses, proteostasis, and lipid metabolism. While this process is typically tightly regulated, constitutive activation of SKN-1/Nrf2 is detrimental to organismal health, this raises interesting questions surrounding the tradeoff between SKN-1/Nrf2 cryoprotection and cellular health and the ability of cells to deactivate stress response pathways post stress. Recent work has determined that transcriptional programs of SKN-1 can be redirected or suppressed to abate negative health outcomes of constitutive activation. Here we will detail the mechanisms by which SKN-1 is controlled, which are important for our understanding of SKN-1/Nrf2 cytoprotection across the lifespan.

Untargeted metabolomics reveals the regulatory effect of geniposidic acid on lipid accumulation in HepG2 cells and Caenorhabditis elegans and validation in hyperlipidemic hamsters

BACKGROUND

Geniposidic acid (GPA) alleviates oxidative stress and inflammation in mice However, whether it can effectively regulate lipid accumulation and prevent hyperlipidemia requires further investigation.

PURPOSE

This study combined the untargeted metabolomics of cells and a Caenorhabditis elegans model to evaluate the anti-hyperlipidemic potential of GPA by modulating oxidative stress and regulating lipid metabolism. A golden hamster model of hyperlipidemia was used to further validate the lipid-lowering effect and mechanism of action of GPA.

METHODS

Chemical staining, immunofluorescence, and flow cytometry were performed to examine the effects of GPA on lipid accumulation and oxidative stress. Untargeted metabolomic analysis of cells and C. elegans was performed using ultra-performance liquid chromatography coupled with quadrupole electrostatic field Orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap MS) to identify biomarkers altered by GPA action, analyze the affected metabolic pathways, and validate the mechanisms by which GPA regulates lipid metabolism and oxidative stress. A golden hamster model of hyperlipidemia was established to test the lipid-lowering effects of GPA. Body weight, biochemical markers, rate-limiting enzymes, and key proteins were assessed. Hematoxylin and eosin (H&E) and Oil Red O staining were performed.

RESULTS

Phenotypic data showed that GPA decreased free fatty acid (FFA)-induced lipid buildup and high reactive oxygen species (ROS) levels, reversed the decrease in mitochondrial membrane potential (MMP), and increased the cellular reduced glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio. GPA also reduces high glucose-induced lipid build-up and ROS production in C. elegans. Metabolomic analysis showed that GPA affected purine, lipid, and amino acid metabolism. Moreover, GPA inhibited xanthine oxidase (XOD), glutamate dehydrogenase (GLDH), fatty acid synthase (FAS), phosphorylation of P38 MAPK, and upregulated the expression of SIRT3 and CPT1A protein production to control lipid metabolism and produce antioxidant benefits in cells and golden hamsters.

CONCLUSION

Current evidence suggests that GPA can effectively regulate lipid metabolism and the oxidative stress response, and has the potential to prevent hyperlipidemia. This study also provided an effective method for evaluating the mechanism of action of GPA.

Sorafenib extends the lifespan of C. elegans through mitochondrial uncoupling mechanism

Sorafenib is a targeted anticancer drug in clinic. Low-dose sorafenib has been reported to activate AMPK through inducing mitochondrial uncoupling without detectable toxicities. AMPK activation has been the approach for extending lifespan, therefore, we investigated the effect of sorafenib on lifespan and physical activity of C. elegans and the underlying mechanisms. In the present study, we found that the effect of sorafenib on C. elegans lifespan was typically hermetic. Sorafenib treatment at higher concentrations (100 μM) was toxic but at lower concentrations (1, 2.5, 5 μM) was beneficial to C. elegans. Sorafenib (1 μM) treatment for whole-life period extended C. elegans lifespan and improved C. elegans physical activity as manifested by increasing pharyngeal pumping and body movement, preserving intestinal barrier integrity, muscle fibers organization and mitochondrial morphology. In addition, sorafenib (1 μM) treatment enhanced C. elegans stress resistance. Sorafenib activated AMPK through inducing mitochondrial uncoupling in C. elegans. Sorafenib treatment activated DAF-16, SKN-1, and increased SOD-3, HSP-16.2, GST-4 expression in C. elegans. Sorafenib treatment induced AMPK-dependent autophagy in C. elegans. We conclude that low-dose sorafenib protects C. elegans against aging through activating AMPK/DAF-16 dependent anti-oxidant pathways and stimulating autophagy responses. Low-dose sorafenib could be a strategy for treating aging and aging-related diseases.

The role of serum-glucocorticoid regulated kinase 1 in reproductive viability: implications from prenatal programming and senescence

OBJECTIVE

Organisms and cellular viability are of paramount importance to living creatures. Disruption of the balance between cell survival and apoptosis results in compromised viability and even carcinogenesis. One molecule involved in keeping this homeostasis is serum-glucocorticoid regulated kinase (SGK) 1. Emerging evidence points to a significant role of SGK1 in cell growth and survival, cell metabolism, reproduction, and life span, particularly in prenatal programming and reproductive senescence by the same token. Whether the hormone inducible SGK1 kinase is a major driver in the pathophysiological processes of prenatal programming and reproductive senescence?

METHOD

The PubMed/Medline, Web of Science, Embase/Ovid, and Elsevier Science Direct literature databases were searched for articles in English focusing on SGK1 published up to July 2023 RESULT: Emerging evidence is accumulating pointing to a pathophysiological role of the ubiquitously expressed SGK1 in the cellular and organismal viability. Under the regulation of specific hormones, extracellular stimuli, and various signals, SGK1 is involved in several biological processes relevant to viability, including cell proliferation and survival, cell migration and differentiation. In line, SGK1 contributes to the development of germ cells, embryos, and fetuses, whereas SGK1 inhibition leads to abnormal gametogenesis, embryo loss, and truncated reproductive lifespan.

CONCLUTION

SGK1 integrates a broad spectrum of effects to maintain the homeostasis of cell survival and apoptosis, conferring viability to multiple cell types as well as both simple and complex organisms, and thus ensuring appropriate prenatal development and reproductive lifespan.

The role of Caenorhabditis elegans in the discovery of natural products for healthy aging

Covering: 2012 to 2023The human population is aging. Thus, the greatest risk factor for numerous diseases, such as diabetes, cancer and neurodegenerative disorders, is increasing worldwide. Age-related diseases do not typically occur in isolation, but as a result of multi-factorial causes, which in turn require holistic approaches to identify and decipher the mode of action of potential remedies. With the advent of C. elegans as the primary model organism for aging, researchers now have a powerful in vivo tool for identifying and studying agents that effect lifespan and health span. Natural products have been focal research subjects in this respect. This review article covers key developments of the last decade (2012-2023) that have led to the discovery of natural products with healthy aging properties in C. elegans. We (i) discuss the state of knowledge on the effects of natural products on worm aging including methods, assays and involved pathways; (ii) analyze the literature on natural compounds in terms of their molecular properties and the translatability of effects on mammals; (iii) examine the literature on multi-component mixtures with special attention to the studied organisms, extraction methods and efforts regarding the characterization of their chemical composition and their bioactive components. (iv) We further propose to combine small in vivo model organisms such as C. elegans and sophisticated analytical approaches ("wormomics") to guide the way to dissect complex natural products with anti-aging properties.

The million-molecule challenge: a moonshot project to rapidly advance longevity intervention discovery

Targeting aging is the future of twenty-first century preventative medicine. Small molecule interventions that promote healthy longevity are known, but few are well-developed and discovery of novel, robust interventions has stagnated. To accelerate longevity intervention discovery and development, high-throughput systems are needed that can perform unbiased drug screening and directly measure lifespan and healthspan metrics in whole animals. C. elegans is a powerful model system for this type of drug discovery. Combined with automated data capture and analysis technologies, truly high-throughput longevity drug discovery is possible. In this perspective, we propose the "million-molecule challenge", an effort to quantitatively assess 1,000,000 interventions for longevity within five years. The WormBot-AI, our best-in-class robotics and AI data analysis platform, provides a tool to achieve the million-molecule challenge for pennies per animal tested.

Nanodrug Delivery Strategies to Signaling Pathways in Alopecia

Over 50% of the global population suffers from hair loss. The mixed results in the treatment of hair loss reveal the limitations of conventional commercial topical drugs. One the one hand, the definite pathogenesis of hair loss is still an enigma. On the other hand, targeted drug carriers ensure the drug therapeutic effect and low side effects. This review highlights the organization and overview of nine crucial signaling pathways associated with hair loss, as well as the development of nanobased topical delivery systems loading the clinical drugs, which will fuel emerging hair loss treatment strategies.

Acyl CoA oxidase: from its expression, structure, folding, and import to its role in human health and disease

β-oxidation of fatty acids is an important metabolic pathway and is a shared function between mitochondria and peroxisomes in mammalian cells. On the other hand, peroxisomes are the sole site for the degradation of fatty acids in yeast. The first reaction of this pathway is catalyzed by the enzyme acyl CoA oxidase housed in the matrix of peroxisomes. Studies in various model organisms have reported the conserved function of the protein in fatty acid oxidation. The importance of this enzyme is highlighted by the lethal conditions caused in humans due to its altered function. In this review, we discuss various aspects ranging from gene expression, structure, folding, and import of the protein in both yeast and human cells. Further, we highlight recent findings on the role of the protein in human health and aging, and discuss the identified mutations in the protein associated with debilitating conditions in patients.

Glycerol 3-phosphate phosphatase/PGPH-2 counters metabolic stress and promotes healthy aging via a glycogen sensing-AMPK-HLH-30-autophagy axis in C. elegans

Metabolic stress caused by excess nutrients accelerates aging. We recently demonstrated that the newly discovered enzyme glycerol-3-phosphate phosphatase (G3PP; gene Pgp), which operates an evolutionarily conserved glycerol shunt that hydrolyzes glucose-derived glycerol-3-phosphate to glycerol, counters metabolic stress and promotes healthy aging in C. elegans. However, the mechanism whereby G3PP activation extends healthspan and lifespan, particularly under glucotoxicity, remained unknown. Here, we show that the overexpression of the C. elegans G3PP homolog, PGPH-2, decreases fat levels and mimics, in part, the beneficial effects of calorie restriction, particularly in glucotoxicity conditions, without reducing food intake. PGPH-2 overexpression depletes glycogen stores activating AMP-activate protein kinase, which leads to the HLH-30 nuclear translocation and activation of autophagy, promoting healthy aging. Transcriptomics reveal an HLH-30-dependent longevity and catabolic gene expression signature with PGPH-2 overexpression. Thus, G3PP overexpression activates three key longevity factors, AMPK, the TFEB homolog HLH-30, and autophagy, and may be an attractive target for age-related metabolic disorders linked to excess nutrients.

2 Hydroxybutyric Acid-Producing Bacteria in Gut Microbiome and Fusobacterium nucleatum Regulates 2 Hydroxybutyric Acid Level In Vivo

2-hydroxybutyric acid (2HB) serves as an important regulatory factor in a variety of diseases. The circulating level of 2HB in serum is significantly higher in multiple diseases, such as cancer and type 2 diabetes (T2D). However, there is currently no systematic study on 2HB-producing bacteria that demonstrates whether gut bacteria contribute to the circulating 2HB pool. To address this question, we used BLASTP to reveal the taxonomic profiling of 2HB-producing bacteria in the human microbiome, which are mainly distributed in the phylum Proteobacteria and Firmicutes. In vitro experiments showed that most gut bacteria (21/32) have at least one path to produce 2HB, which includes Aspartic acid, methionine, threonine, and 2-aminobutyric acid. Particularly, Fusobacterium nucleatum has the strongest ability to synthesize 2HB, which is sufficient to alter colon 2HB concentration in mice. Nevertheless, neither antibiotic (ABX) nor Fusobacterium nucleatum gavage significantly affected mouse serum 2HB levels during the time course of this study. Taken together, our study presents the profiles of 2HB-producing bacteria and demonstrates that gut microbiota was a major contributor to 2HB concentration in the intestinal lumen but a relatively minor contributor to serum 2HB concentration.