Urolithin A

The Gut Connection: Exploring the Possibility of Implementing Gut Microbial Metabolites in Lymphoma Treatment.[Pubmed:38672546]

Cancers (Basel). 2024 Apr 11;16(8):1464.

Recent research has implicated the gut microbiota in the development of lymphoma. Dysbiosis of the gut microbial community can disrupt the production of gut microbial metabolites, thereby impacting host physiology and potentially contributing to lymphoma. Dysbiosis-driven release of gut microbial metabolites such as lipopolysaccharides can promote chronic inflammation, potentially elevating the risk of lymphoma. In contrast, gut microbial metabolites, such as short-chain fatty acids, have shown promise in preclinical studies by promoting regulatory T-cell function, suppressing inflammation, and potentially preventing lymphoma. Another metabolite, Urolithin A, exhibited immunomodulatory and antiproliferative properties against lymphoma cell lines in vitro. While research on the role of gut microbial metabolites in lymphoma is limited, this article emphasizes the need to comprehend their significance, including therapeutic applications, molecular mechanisms of action, and interactions with standard chemotherapies. The article also suggests promising directions for future research in this emerging field of connection between lymphoma and gut microbiome.

Effects of (poly)phenols on circadian clock gene-mediated metabolic homeostasis in cultured mammalian cells: a scoping review.[Pubmed:38648895]

Adv Nutr. 2024 Apr 20:100232.

Metabolic homeostasis is regulated by circadian clocks. Disruption to our circadian clocks, by lifestyle behaviors such as timing of eating and sleeping, has been linked to increased rates of metabolic disorders. There is now considerable evidence that selected dietary (poly)phenols, including flavonoids, phenolic acids and tannins, may modulate both metabolic and circadian processes. This review evaluates the effects of (poly)phenols on circadian clock genes and linked metabolic homeostasis in vitro, and potential mechanisms of action, by critically evaluating the literature on mammalian cells. A systematic search was conducted to ensure full coverage of the literature, and identified 43 relevant studies addressing the effects of (poly)phenols on cellular circadian processes. Nobiletin and tangeretin, found in citrus, (-)-epigallocatechin-3-gallate from green tea, Urolithin A, a gut microbial metabolite from ellagitannins in fruit, curcumin, bavachalcone, cinnamic acid and resveratrol at low micromolar concentrations all affect circadian molecular processes in multiple types of synchronized cells. Nobiletin emerges as a putative Retinoic acid-related Orphan Receptor (RORalpha/gamma) agonist, leading to induction of the circadian regulator Brain and Muscle ARNT-Like 1 (BMAL1), and increased Period Circadian Regulator 2 (PER2) amplitude and period. These effects are clear despite substantial variations in the protocols employed, and this review suggests a methodological framework to help future study design in this emerging area of research.

Methylated urolithin A, mitigates cognitive impairment by inhibiting NLRP3 inflammasome and ameliorating mitochondrial dysfunction in aging mice.[Pubmed:38636727]

Neuropharmacology. 2024 Apr 16;252:109950.

Effective therapeutic interventions for elderly patients are lacking, despite advances in pharmacotherapy. Methylated Urolithin A (mUro A), a modified ellagitannin (ET)-derived metabolite, exhibits anti-inflammatory, antioxidative, and anti-apoptotic effects. Current research has primarily investigated the neuroprotective effects of mUroA in aging mice and explored the underlying mechanisms. Our study used an in vivo aging model induced by d-galactose (D-gal) to show that mUro A notably improved learning and memory, prevented synaptic impairments by enhancing synaptic protein expression and increasing EPSCs, and reduced oxidative damage in aging mice. mUro A alleviated the activation of the NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome, leading to reduced glial cell activity and neuroinflammation in both accelerated aging and naturally senescent mouse models. Moreover, mUroA enhanced the activity of TCA cycle enzymes (PDH, CS, and OGDH), decreased 8-OHdG levels, and raised ATP and NAD(+) levels within the mitochondria. At the molecular level, mUro A decreased phosphorylated p53 levels and increased the expression of peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha), thus enhancing mitochondrial function. In conclusion, mUro A alleviates cognitive impairment in aging mice by suppressing neuroinflammation through NLRP3 inflammasome inhibition and restoring mitochondrial function via the p53-PGC-1alpha pathway. This suggests its potential therapeutic agent for brain aging and aging-related diseases.

Gut microbiota-generated metabolites: missing puzzles to hosts' health, diseases, and aging.[Pubmed:38627947]

BMB Rep. 2024 Apr 17:6194.

The gut microbiota, an intricate community of bacteria residing in the gastrointestinal system, assumes a pivotal role in various physiological processes. Beyond its function in food breakdown and nutrient absorption, gut microbiota exerts a profound influence on immune and metabolic modulation by producing diverse gut microbiota-generated metabolites (GMGMs). These small molecules hold potential to impact host health via multiple pathways, which exhibit remarkable diversity, and have gained increasing attention in recent studies. Here, we elucidate the intricate implications and significant impacts of four specific metabolites, Urolithin A (UA), equol, Trimethylamine N-oxide (TMAO), and imidazole propionate, in shaping human health. Meanwhile, we also look into the advanced research on GMGMs, which demonstrate promising curative effects and hold great potential for further clinical therapies. Notably, the emergence of positive outcomes from clinical trials involving GMGMs, typified by UA, emphasizes their promising prospects in the pursuit of improved health and longevity. Collectively, the multifaceted impacts of GMGMs present intriguing avenues for future research and therapeutic interventions.

Urolithin A affects cellular migration and modulates matrix metalloproteinase expression in colorectal cancer cells.[Pubmed:38622949]

Cell Biochem Funct. 2024 Apr;42(3):e4019.

Colorectal cancer (CRC) is the world's second most common gastrointestinal malignancy. Preventing tumor cell proliferation and dissemination is critical for patient survival. Polyphenols have a variety of health advantages and can help prevent cancer. The current study examined different cellular activities of the gut-microbiota metabolite Urolithin A (UA) on several colon cancer cell lines. The results revealed that UA suppressed cell growth in a dose- and time-dependent manner. In the current investigation, UA substantially affected cell migration in the wound-healing experiment and greatly decreased the number of colonies generated in each CRC cell culture. UA decreased cellular migration in CRC cells 48 h after treatment, which was significant (p < .001) compared to the migration rate in untreated cells. When compared to untreated cells, UA slowed the process of colony formation by reducing the number of colonies or altering their morphological shape. The western blot analysis investigation revealed that UA inhibits cellular metastasis by lowering the expression levels of matrix metalloproteinases 1 and 2 (MMP1 and MMP2) by more than 43% and 41% (p < .001) in HT29, 28% and 149% (p < .001) in SW480, and 90% and 74% (p < .001) in SW620, respectively, at a 100 microM dosage of UA compared to the control. Surprisingly, at a 100 microM dosage of UA, the expression levels of the tissue inhibitor of metalloproteinases 1 (TIMP1) were elevated in HT29, SW480, and SW620 cells treated with 100 microM of UA by more than 89%, 57%, and 29%, respectively. Our findings imply that UA has anticancer properties and might be used therapeutically to treat CRC. The findings provided the first indication of the influence of UA on cellular migration and metastasis in colon cancer cells. All of these data showed that UA might be used as an adjuvant therapy in the treatment of various forms of CRC.

Urolithin A inhibits breast cancer progression via activating TFEB-mediated mitophagy in tumor macrophages.[Pubmed:38615740]

J Adv Res. 2024 Apr 12:S2090-1232(24)00153-X.

INTRODUCTION: Urolithin A (UA) is a naturally occurring compound that is converted from ellagitannin-like precursors in pomegranates and nuts by intestinal flora. Previous studies have found that UA exerts tumor-suppressive effects through antitumor cell proliferation and promotion of memory T-cell expansion, but its role in tumor-associated macrophages remains unknown. OBJECTIVES: Our study aims to reveal how UA affects tumor macrophages and tumor cells to inhibit breast cancer progression. METHODS: Observe the effect of UA treatment on breast cancer progression though in vivo and in vitro experiments. Western blot and PCR assays were performed to discover that UA affects tumor macrophage autophagy and inflammation. Co-ip and Molecular docking were used to explore specific molecular mechanisms. RESULTS: We observed that UA treatment could simultaneously inhibit harmful inflammatory factors, especially for InterleuKin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha), in both breast cancer cells and tumor-associated macrophages, thereby improving the tumor microenvironment and delaying tumor progression. Mechanistically, UA induced the key regulator of autophagy, transcription factor EB (TFEB), into the nucleus in a partially mTOR-dependent manner and inhibited the ubiquitination degradation of TFEB, which facilitated the clearance of damaged mitochondria via the mitophagy-lysosomal pathway in macrophages under tumor supernatant stress, and reduced the deleterious inflammatory factors induced by the release of nucleic acid from damaged mitochondria. Molecular docking and experimental studies suggest that UA block the recognition of TFEB by 1433 and induce TFEB nuclear localization. Notably, UA treatment demonstrated inhibitory effects on tumor progression in multiple breast cancer models. CONCLUSION: Our study elucidated the anti-breast cancer effect of UA from the perspective of tumor-associated macrophages. Specifically, TFEB is a crucial downstream target in macrophages.

Effects of solid lipid nanocarrier containing methyl urolithin A by coating folate-bound chitosan and evaluation of its anti-cancer activity.[Pubmed:38600497]

BMC Biotechnol. 2024 Apr 10;24(1):18.

BACKGROUND: Nanotechnology-based drug delivery systems have received much attention over the past decade. In the present study, we synthesized Methyl Urolithin A-loaded solid lipid nanoparticles decorated with the folic acid-linked chitosan layer called MuSCF-NPs and investigated their effects on cancer cells. METHODS: MuSCF-NPs were prepared using a high-pressure homogenization method and characterized using FTIR, FESEM, DLS, and zeta potential methods. Drug encapsulation was assessed by spectrophotometry and its cytotoxic effect on various cancer cells (MDA-MB231, MCF-7, PANC, AGS, and HepG2) by the MTT method. Antioxidant activity was assessed by the ABTS and DPPH methods, followed by expression of genes involved in oxidative stress and apoptosis by qPCR and flow cytometry. RESULTS: The results showed the formation of monodisperse and stable round nanoparticles with a size of 84.8 nm. The drug loading efficiency in MuSCF-NPs was reported to be 88.6%. MuSCF-NPs exhibited selective cytotoxicity against MDA-MB231 cells (IC(50) = 40 mug/mL). Molecular analysis showed a significant increase in the expression of Caspases 3, 8, and 9, indicating that apoptosis was occurring in the treated cells. Moreover, flow cytometry results showed that the treated cells were arrested in his SubG1 phase, confirming the pro-apoptotic effect of the nanoparticles. The results indicate a high antioxidant effect of the nanoparticles with IC(50) values ​​of 45 mug/mL and 1500 mug/mL against ABTS and DPPH, respectively. The reduction of catalase gene expression confirmed the pro-oxidant effect of nanoparticles in cancer cells treated at concentrations of 20 and 40 mug/mL. CONCLUSIONS: Therefore, our findings suggest that the MuSCF-NPs are suitable candidates, especially for breast cancer preclinical studies.

Urolithin A attenuates bupivacaine-induced neurotoxicity in SH-SY5Y cells by regulating the SIRT1-activated PI3K/AKT pathway.[Pubmed:38587058]

Histol Histopathol. 2024 Mar 25:18737.

Urolithin A (UroA) is well-recognized for its anti-oxidative, anti-inflammatory, and immunomodulatory potentials and has been proven to have neuroprotective effects. Nevertheless, the potential of UroA on bupivacaine (BUP)-induced neurotoxicity has never been reported. Using SH-SY5Y cells to establish a cell model, it was revealed that BUP stimulated cell viability reduction, LDH release increase, and suppression of SIRT1-activated PI3K/AKT signaling in SH-SY5Y cells, whereas UroA treatment caused an effective abrogation of the effects of BUP. Besides, SIRT1 overexpression caused an enhancement in the activity of PI3K/AKT signaling in BUP and UroA co-treated cells, indicating that SIRT1 mediated the activity of PI3K/AKT signaling. Moreover, UroA inhibited BUP-induced apoptosis, oxidative stress, and inflammatory responses in SH-SY5Y cells. However, the effects of UroA on BUP-induced neurotoxicity were all abated by inhibiting SIRT1 or PI3K/AKT signaling through EX527 or LY294002. In conclusion, UroA protected SH-SY5Y cells against BUP-induced injuries through PI3K/AKT signaling in a SIRT1-dependent manner.

The effects of urolithin A on poly I:C-induced microglial activation.[Pubmed:38577490]

Front Cell Neurosci. 2024 Mar 20;18:1343562.

Neuroinflammation can be triggered by various stimuli, including viral infections. Viruses can directly invade the brain and infect neuronal cells or indirectly trigger a "cytokine storm" in the periphery that eventually leads to microglial activation in the brain. While this initial activation of microglial cells is important for viral clearance, chronic activation leads to excessive inflammation and oxidative stress, which can be neurotoxic. Remarkebly, recent studies have shown that certain viruses such as influenza A virus, coronavirus, herpes virus and Epstein-Barr virus may be involved in the development of neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and multiple sclerosis. Therefore, it is important to find therapeutic strategies against chronic neuroinflammation triggered by viral infections. Here, we investigated the effects of Urolithin A (UA) on microglial activation in vitro induced by a viral mimetic, poly I:C, in a triple co-culture system of neurons, astrocytes and microglial cells. Immunocytochemistry was used to perform a comprehensive single-cell analysis of the morphological changes of microglia as an indicator of their reactive state. Treatment with UA significantly prevented the poly I:C-induced reactive state of microglia, which was characterized by increased expression of the microglial activation markers CD68 and IBA-1. UA restored the poly I:C-induced morphology by restoring microglial ramification. In addition, UA was able to reduce the release of the pro-inflammatory mediators CCL2, TNF-alpha, and IL-1beta and showed a trend toward attenuation of cellular ROS production in poly I:C-treated cultures. Overall, this study suggests that UA as a component of a healthy diet may help prevent virus-induced neuroinflammation and may have therapeutic potential for future studies to prevent or treat neurodegenerative diseases by targeting the associated neuroinflammatory processes.

ApoE4 dysregulation incites depressive symptoms and mitochondrial impairments in mice.[Pubmed:38506067]

J Cell Mol Med. 2024 Apr;28(7):e18160.

Apolipoprotein E4 (ApoE4) is involved in the stress-response processes and is hypothesized to be a risk factor for depression by means of mitochondrial dysfunction. However, their exact roles and underlying mechanisms are largely unknown. ApoE4 transgenic mice (B6. Cg-ApoE(tm1Unc) Cdh18(Tg() GFAP(-APOE i4)1Hol) /J) were subjected to stress (lipopolysaccharides, LPS) to elucidate the aetiology of ApoE4-induced depression. LPS treatment significantly aggravated depression-like behaviours, concurrent with neuroinflammation and impaired mitochondrial changes, and melatonin/Urolithin A (UA) + 5-aminoimidazole-4-carboxamide 1-beta-D-ribofuranoside (AICAR) reversed these effects in ApoE4 mice. Concurrently, ApoE4 mice exhibited mitophagy deficits, which could be further exacerbated by LPS stimulation, as demonstrated by reduced Atg5, Beclin-1 and Parkin levels, while PINK1 levels were increased. However, these changes were reversed by melatonin treatment. Additionally, proteomic profiling suggested mitochondria-related signalling and network changes in ApoE4 mice, which may underlie the exaggerated response to LPS. Furthermore, HEK 293T cells transfected with ApoE4 showed mitochondria-associated protein and mitophagy defects, including PGC-1alpha, TFAM, p-AMPKalpha, PINK1 and LC3B impairments. Additionally, it aggravates mitochondrial impairment (particularly mitophagy), which can be attenuated by triggering autophagy. Collectively, ApoE4 dysregulation enhanced depressive behaviour upon LPS stimulation.

Urolithin A exerts anti-tumor effects on gastric cancer via activating autophagy-Hippo axis and modulating the gut microbiota.[Pubmed:38489081]

Naunyn Schmiedebergs Arch Pharmacol. 2024 Mar 15.

Gastric cancer (GC) treatment regimens are still unsatisfactory. Recently, Urolithin A (UroA) has gained tremendous momentum due to its anti-tumor properties. However, the therapeutic effect and underlying mechanisms of UroA in GC are unclear. We explored the effects and related mechanisms of UroA on GC both in vivo and in vitro. A Cell Counting Kit-8 was used to determine the influence of UroA on the proliferation of GC cell lines. The Autophagy inhibitor 3-methyladenine (3MA) was employed to clarify the role of autophagy in the anti-tumor effect of UroA. Simultaneously, we detected the core-component proteins involved in autophagy and its downstream pathways. Subsequently, the in vivo anti-tumor effect of UroA was determined using a xenograft mouse model. Western blotting was used to detect the core protein components of the anti-tumor pathways, and 16S rDNA sequencing was used to detect the effect of UroA on the gut microbiota. We found that UroA suppressed tumor progression. The use of 3MA undermined the majority of the inhibitory effect of UroA on tumor cell proliferation, further confirming the importance of autophagy in the anti-tumor effect of UroA. Invigorating of autophagy activated the downstream Hippo pathway, thereby inhibiting the Warburg effect and promoting cell apoptosis. In addition, UroA modulated the composition of the gut microbiota, as indicated by the increase of probiotics and the decrease of pathogenic bacteria. Our research revealed new anti-tumor mechanisms of UroA, which may be a promising candidate for GC treatment.

Enhancing healthy aging with small molecules: A mitochondrial perspective.[Pubmed:38483176]

Med Res Rev. 2024 Mar 14.

The pursuit of enhanced health during aging has prompted the exploration of various strategies focused on reducing the decline associated with the aging process. A key area of this exploration is the management of mitochondrial dysfunction, a notable characteristic of aging. This review sheds light on the crucial role that small molecules play in augmenting healthy aging, particularly through influencing mitochondrial functions. Mitochondrial oxidative damage, a significant aspect of aging, can potentially be lessened through interventions such as coenzyme Q10, alpha-lipoic acid, and a variety of antioxidants. Additionally, this review discusses approaches for enhancing mitochondrial proteostasis, emphasizing the importance of mitochondrial unfolded protein response inducers like doxycycline, and agents that affect mitophagy, such as Urolithin A, spermidine, trehalose, and taurine, which are vital for sustaining protein quality control. Of equal importance are methods for modulating mitochondrial energy production, which involve nicotinamide adenine dinucleotide boosters, adenosine 5'-monophosphate-activated protein kinase activators, and compounds like metformin and mitochondria-targeted tamoxifen that enhance metabolic function. Furthermore, the review delves into emerging strategies that encourage mitochondrial biogenesis. Together, these interventions present a promising avenue for addressing age-related mitochondrial degradation, thereby setting the stage for the development of innovative treatment approaches to meet this extensive challenge.

Urolithin A Ameliorates Athletic Ability and Intestinal Microbiota in Sleep Deprivation from the Perspective of the Gut-Muscle Axis.[Pubmed:38468112]

Mol Nutr Food Res. 2024 Apr;68(7):e2300599.

SCOPE: Urolithin A (UA), a gut-microbiota-derived metabolite of ellagic acid, presents various benefits to intestinal microecology. The presence of "gut-muscle axis" regulating the onset and progression of exercise-related physical frailty and sarcopenia has been recently hypothesized. This study aims to explore the underlying mechanism of gut-muscle axis by which UA enhances muscle strength and fatigue resistance of sleep-deprived (SD) mice. METHODS AND RESULTS: UA is gavaged to C57BL/6 mice (50 mg kg(-1) bw) before 48-h SD. The results indicate that pretreatment of UA significantly enhances motor ability and energy metabolism. The inflammation is suppressed, and intestinal permeability is improved after prophylactic treatment with UA. The decreased level of serum lipopolysaccharide (LPS) is concomitant with augmentation of the intestinal tight junction proteins. 16s rRNA analysis of colonic contents reveals that UA significantly reduces the abundance of Clostridia_UCG-014 and Candidatus_Saccharimonas, and upregulates Lactobacillus and Muribaculaceae. UA probably influences on gut microbial functions via several energy metabolism pathways, such as carbon metabolism, phosphotransferase system (PTS), and ATP binding cassette (ABC) transporters. CONCLUSIONS: The dietary intervention of UA helps to create a systemic protection, a bidirectional communication connecting the gut microbiota with muscle system, able to alleviate SD-induced mobility impairment and gut dysbiosis.