@article {2400, title = {Inflammation-specific targeted carriers for local drug delivery to inflammatory bowel disease.}, journal = {Biomaterials}, volume = {281}, year = {2022}, month = {2022 Jan 05}, pages = {121364}, abstract = {

Delivering drugs directly to the inflamed intestinal sites to treat inflammatory bowel disease (IBD), particularly Crohn{\textquoteright}s and ulcerative colitis, is highly challenging. Recent advances in colitis therapy medications are expanding opportunities for improving local on-site drug availability by minimising the associated systemic side-effects. Drug delivery with targeted carrier systems has shown the potential to increase site-specificity, stability, and therapeutic efficacy. Herein, we report the development of a strong anionic charged inflammation targeted nanocarriers (IT-NCs) loaded with an immunosuppressant model drug. This system showed preferential adhesion on a charge-modified surface in vitro, and in both dextran sulfate sodium (DSS) and TNBS colitis mice in vivo models. IT-NCs showed improved colitis phenotype therapeutic efficacy in both animal models compared to free drug. Furthermore, ex vivo study of colon tissue biopsies from patients with colitis revealed that IT-NCs adhered preferentially to inflamed biopsies compared to normal. Together, our results suggest that IT-NCs have promising therapeutic potential as delivery carriers{\textquoteright} in colitis management.

}, issn = {1878-5905}, doi = {10.1016/j.biomaterials.2022.121364}, author = {Kotla, Niranjan G and Singh, Rajbir and Baby, Becca V and Rasala, Swetha and Rasool, Jawad and Hynes, Sean O and Martin, Darrell and Egan, Laurence J and Vemula, Praveen K and Jala, Venkatakrishna R and Rochev, Yury and Pandit, Abhay} } @article {1603, title = {Enhancement of the gut barrier integrity by a microbial metabolite through the Nrf2 pathway.}, journal = {Nat Commun}, volume = {10}, year = {2019}, month = {2019 01 09}, pages = {89}, abstract = {

The importance of gut microbiota in human health and pathophysiology is undisputable. Despite the abundance of metagenomics data, the functional dynamics of gut microbiota in human health and disease remain elusive. Urolithin A (UroA), a major microbial metabolite derived from polyphenolics of berries and pomegranate fruits displays anti-inflammatory, anti-oxidative, and anti-ageing activities. Here, we show that UroA and its potent synthetic analogue (UAS03) significantly enhance gut barrier function and inhibit unwarranted inflammation. We demonstrate that UroA and UAS03 exert their barrier functions through activation of aryl hydrocarbon receptor (AhR)- nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent pathways to upregulate epithelial tight junction proteins. Importantly, treatment with these compounds attenuated colitis in pre-clinical models by remedying barrier dysfunction in addition to anti-inflammatory activities. Cumulatively, the results highlight how microbial metabolites provide two-pronged beneficial activities at gut epithelium by enhancing barrier functions and reducing inflammation to protect from colonic diseases.

}, keywords = {Animals, Basic Helix-Loop-Helix Transcription Factors, Caco-2 Cells, Coumarins, Epithelial Cells, Gene Expression Regulation, HT29 Cells, Humans, Intestinal Mucosa, Macrophages, Mice, Mice, Inbred C57BL, Mice, Knockout, NF-E2-Related Factor 2, Receptors, Aryl Hydrocarbon, Specific Pathogen-Free Organisms, Tight Junction Proteins}, issn = {2041-1723}, doi = {10.1038/s41467-018-07859-7}, author = {Singh, Rajbir and Chandrashekharappa, Sandeep and Bodduluri, Sobha R and Baby, Becca V and Hegde, Bindu and Kotla, Niranjan G and Hiwale, Ankita A and Saiyed, Taslimarif and Patel, Paresh and Vijay-Kumar, Matam and Langille, Morgan G I and Douglas, Gavin M and Cheng, Xi and Rouchka, Eric C and Waigel, Sabine J and Dryden, Gerald W and Alatassi, Houda and Zhang, Huang-Ge and Haribabu, Bodduluri and Vemula, Praveen K and Jala, Venkatakrishna R} } @article {1582, title = {Urolithin A, a Novel Natural Compound to Target PI3K/AKT/mTOR Pathway in Pancreatic Cancer.}, journal = {Mol Cancer Ther}, volume = {18}, year = {2019}, month = {2019 Feb}, pages = {301-311}, abstract = {

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy and is highly resistant to standard treatment regimens. Targeted therapies against , a mutation present in an overwhelming majority of PDAC cases, have been largely ineffective. However, inhibition of downstream components in the KRAS signaling cascade provides promising therapeutic targets in the management of PDAC and warrants further exploration. Here, we investigated Urolithin A (Uro A), a novel natural compound derived from pomegranates, which targets numerous kinases downstream of KRAS, in particular the PI3K/AKT/mTOR signaling pathways. We showed that treatment of PDAC cells with Uro A blocked the phosphorylation of AKT and p70S6K successfully inhibited the growth of tumor xenografts, and increased overall survival of Ptf1a;LSL-Kras;Tgfbr2 (PKT) mice compared with vehicle or gemcitabine therapy alone. Histologic evaluation of these Uro A-treated tumor samples confirmed mechanistic actions of Uro A via decreased phosphorylation of AKT and p70S6K, reduced proliferation, and increased cellular apoptosis in both xenograft and PKT mouse models. In addition, Uro A treatment reprogrammed the tumor microenvironment, as evidenced by reduced levels of infiltrating immunosuppressive cell populations such as myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. Overall, this work provides convincing preclinical evidence for the utility of Uro A as a therapeutic agent in PDAC through suppression of the PI3K/AKT/mTOR pathway.

}, issn = {1538-8514}, doi = {10.1158/1535-7163.MCT-18-0464}, author = {Totiger, Tulasigeri M and Srinivasan, Supriya and Jala, Venkatakrishna R and Lamichhane, Purushottam and Dosch, Austin R and Gaidarski, Alexander A and Joshi, Chandrashekhar and Rangappa, Shobith and Castellanos, Jason and Vemula, Praveen Kumar and Chen, Xi and Kwon, Deukwoo and Kashikar, Nilesh and VanSaun, Michael and Merchant, Nipun B and Nagathihalli, Nagaraj S} } @article {1200, title = {Targeted delivery of microbial metabolite, urolithin A protects from chemically (DSS or TNBS) induced colitis in pre-clinical models}, journal = {The Journal of Immunology}, volume = {198}, year = {2017}, pages = {65.6{\textendash}65.6}, abstract = {

Epidemiological data suggests that consumption of diets rich in phytochemicals are protective in inflammatory bowel diseases (IBDs). However, the beneficial effects are not uniform among individuals and attributed to variations in gut microbiota, and altered capacity to generate certain metabolites. Urolithin A (UroA) (3,8-dihydroxybenzo[c]chromen-6-one) is a microbial metabolite, derived from ellagic acid and ellagitannins, major poly phenolic components in berries and pomegranates. Here, we examined therapeutic applications of UroA and mechanisms of action in IBDs. Our studies suggested that UroA significantly reduced LPS induced inflammatory mediators (e.g., IL-6, TNF-alpha and IL-12) as well as ROS production in mouse bone marrow-derived macrophages (BMDMs), dendritic and THP1 cells. Most importantly, UroA also reduced LPS induced systemic inflammation in mouse models. Next, we examined therapeutic applications of UroA in dextran sodium sulphate (DSS)-induced, 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis models. Treatment with UroA significantly reduced both acute and chronic DSS-induced colitis as well as TNBS induced colitis in mouse models. Most importantly, delivery of UroA utilizing inflammation targeting oral nano-particles (single treatment regimen) effectively mitigated the colitis in both models. In summary, these results highlight even presence of single microbial metabolite at right location at right time will have significant beneficial effects to protect from adverse inflammatory activities.

}, issn = {0022-1767}, url = {http://www.jimmunol.org/content/198/1_Supplement/65.6}, author = {Singh, Rajbir and Hegde, Bindu and Von Baby, Becca and Sadeep, C and Kotla, Niranjan and Chandrasekar, Bhargavi and Marepally, Srujan and Bodduluri, Haribabu and Vemula, Praveen K and Jala, Venkatakrishna R} } @article {617, title = {Gut Microbiota Conversion of Dietary Ellagic Acid into Bioactive Phytoceutical Urolithin A Inhibits Heme Peroxidases.}, journal = {PLoS One}, volume = {11}, year = {2016}, month = {2016}, pages = {e0156811}, abstract = {

Numerous studies signify that diets rich in phytochemicals offer many beneficial functions specifically during pathologic conditions, yet their effects are often not uniform due to inter-individual variation. The host indigenous gut microbiota and their modifications of dietary phytochemicals have emerged as factors that greatly influence the efficacy of phytoceutical-based intervention. Here, we investigated the biological activities of one such active microbial metabolite, Urolithin A (UA or 3,8-dihydroxybenzo[c]chromen-6-one), which is derived from the ellagic acid (EA). Our study demonstrates that UA potently inhibits heme peroxidases i.e. myeloperoxidase (MPO) and lactoperoxidase (LPO) when compared to the parent compound EA. In addition, chrome azurol S (CAS) assay suggests that EA, but not UA, is capable of binding to Fe3+, due to its catechol-like structure, although its modest heme peroxidase inhibitory activity is abrogated upon Fe3+-binding. Interestingly, UA-mediated MPO and LPO inhibition can be prevented by innate immune protein human NGAL or its murine ortholog lipocalin 2 (Lcn2), implying the complex nature of host innate immunity-microbiota interactions. Spectral analysis indicates that UA inhibits heme peroxidase-catalyzed reaction by reverting the peroxidase back to its inactive native state. In support of these in vitro results, UA significantly reduced phorbol myristate acetate (PMA)-induced superoxide generation in neutrophils, however, EA failed to block the superoxide generation. Treatment with UA significantly reduced PMA-induced mouse ear edema and MPO activity compared to EA treated mice. Collectively, our results demonstrate that microbiota-mediated conversion of EA to UA is advantageous to both host and microbiota i.e. UA-mediated inhibition of pro-oxidant enzymes reduce tissue inflammation, mitigate non-specific killing of gut bacteria, and abrogate iron-binding property of EA, thus providing a competitive edge to the microbiota in acquiring limiting nutrient iron and thrive in the gut.

}, issn = {1932-6203}, doi = {10.1371/journal.pone.0156811}, author = {Saha, Piu and Yeoh, Beng San and Singh, Rajbir and Chandrasekar, Bhargavi and Vemula, Praveen Kumar and Haribabu, Bodduluri and Vijay-Kumar, Matam and Jala, Venkatakrishna R} }