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Lee HJ, Min L, Gao J, Matta S, Drel V, Saliba A, Tamayo I, Montellano R, Hejazi L, Maity S, Xu G, Grajeda BI, Roy S, Hallows KR, Choudhury GG, Kasinath BS, Sharma K. Female protection against diabetic kidney disease is regulated by kidney-specific AMPK activity. Diabetes 2024:db230807. [PMID: 38656940 DOI: 10.2337/db23-0807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 04/15/2024] [Indexed: 04/26/2024]
Abstract
Reduced kidney AMPK activity is associated with nutrient stress-induced chronic kidney disease (CKD) in male mice. In contrast, female mice resist nutrient stress-induced CKD. The role of kidney AMPK in sex-related organ protection against nutrient stress and metabolite changes were evaluated in diabetic kidney tubule-specific AMPKγ2KO (KTAMPKγ2KO) male and female mice. In WT males, diabetes increased albuminuria, urinary kidney injury molecule-1, hypertension, kidney p70S6K phosphorylation, and kidney matrix accumulation; these features were not exacerbated with KTAMPKγ2KO. Whereas WT females had protection against diabetes induced kidney injury, KTAMPKγ2KO led to loss of female protection against kidney disease. 17β-estradiol ameliorated high glucose-induced AMPK inactivation, p70S6K phosphorylation and matrix protein accumulation in kidney tubule cells. The mechanism for female protection against diabetes-induced kidney injury is likely via an estrogen-AMPK pathway, as inhibition of AMPK led to loss of estrogen protection to glucose-induced mTORC1 activation and matrix production. RNA-seq and metabolomic analysis identified a decrease in the degradation pathway of phenylalanine and tyrosine resulting in increased urinary phenylalanine and tyrosine levels in females. The metabolite levels correlated with loss of female protection. The findings provide new insights to explain evolutionary advantages to females during states of nutrient challenges.
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Affiliation(s)
- Hak Joo Lee
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
- South Texas Veterans Health Care System, San Antonio, Texas
| | - Liang Min
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Jingli Gao
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Shane Matta
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Viktor Drel
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Afaf Saliba
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Ian Tamayo
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Richard Montellano
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Leila Hejazi
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Soumya Maity
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Guogang Xu
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
| | - Brian I Grajeda
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas, El Paso, Texas
| | - Sourav Roy
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas, El Paso, Texas
| | - Kenneth R Hallows
- USC/UKRO Kidney Research Center, Division of Nephrology and Hypertension, University of Southern California Keck School of Medicine, Los Angeles, California
| | - Goutam Ghosh Choudhury
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
- South Texas Veterans Health Care System, San Antonio, Texas
| | - Balakuntalam S Kasinath
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
- South Texas Veterans Health Care System, San Antonio, Texas
| | - Kumar Sharma
- Center for Precision Medicine, Division of Nephrology, University of Texas Health, San Antonio, Texas
- South Texas Veterans Health Care System, San Antonio, Texas
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Zhang R, Peng X, Du JX, Boohaker R, Estevao IL, Grajeda BI, Cox MB, Almeida IC, Lu W. Oncogenic KRASG12D Reprograms Lipid Metabolism by Upregulating SLC25A1 to Drive Pancreatic Tumorigenesis. Cancer Res 2023; 83:3739-3752. [PMID: 37695315 PMCID: PMC10840918 DOI: 10.1158/0008-5472.can-22-2679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/24/2022] [Accepted: 09/07/2023] [Indexed: 09/12/2023]
Abstract
Pancreatic cancer is a highly lethal disease with obesity as one of the risk factors. Oncogenic KRAS mutations are prevalent in pancreatic cancer and can rewire lipid metabolism by altering fatty acid (FA) uptake, FA oxidation (FAO), and lipogenesis. Identification of the underlying mechanisms could lead to improved therapeutic strategies for treating KRAS-mutant pancreatic cancer. Here, we observed that KRASG12D upregulated the expression of SLC25A1, a citrate transporter that is a key metabolic switch to mediate FAO, fatty acid synthesis, glycolysis, and gluconeogenesis. In genetically engineered mouse models and human pancreatic cancer cells, KRASG12D induced SLC25A1 upregulation via GLI1, which directly stimulated SLC25A1 transcription by binding its promoter. The enhanced expression of SLC25A1 increased levels of cytosolic citrate, FAs, and key enzymes in lipid metabolism. In addition, a high-fat diet (HFD) further stimulated the KRASG12D-GLI1-SLC25A1 axis and the associated increase in citrate and FAs. Pharmacologic inhibition of SLC25A1 and upstream GLI1 significantly suppressed pancreatic tumorigenesis in KrasG12D/+ mice on a HFD. These results reveal a KRASG12D-GLI1-SLC25A1 regulatory axis, with SLC25A1 as an important node that regulates lipid metabolism during pancreatic tumorigenesis, thus indicating an intervention strategy for oncogenic KRAS-driven pancreatic cancer. SIGNIFICANCE Upregulation of SLC25A1 induced by KRASG12D-GLI1 signaling rewires lipid metabolism and is exacerbated by HFD to drive the development of pancreatic cancer, representing a targetable metabolic axis to suppress pancreatic tumorigenesis.
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Affiliation(s)
- Ruowen Zhang
- Department of Medicine, Stony Brook University, Stony Brook, New York, USA
| | - Xiaogang Peng
- Depart of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, Texas, USA
| | - James Xianxing Du
- Department of Medicine, Stony Brook University, Stony Brook, New York, USA
- Depart of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, Texas, USA
| | - Rebecca Boohaker
- Oncology Department, Southern Research Institute, Birmingham, Alabama, USA
| | - Igor L Estevao
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas, USA
| | - Brian I Grajeda
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas, USA
| | - Marc B Cox
- Depart of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, Texas, USA
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas, USA
| | - Igor C Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas, USA
| | - Weiqin Lu
- Department of Medicine, Stony Brook University, Stony Brook, New York, USA
- Depart of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, Texas, USA
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Kulkarni A, Delgadillo FM, Gayathrinathan S, Grajeda BI, Roy S. Current Status of Omics Studies Elucidating the Features of Reproductive Biology in Blood-Feeding Insects. Insects 2023; 14:802. [PMID: 37887814 PMCID: PMC10607566 DOI: 10.3390/insects14100802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/28/2023]
Abstract
Female insects belonging to the genera Anopheles, Aedes, Glossina, and Rhodnius account for the majority of global vector-borne disease mortality. In response to mating, these female insects undergo several molecular, physiological, and behavioral changes. Studying the dynamic post-mating molecular responses in these insects that transmit human diseases can lead to the identification of potential targets for the development of novel vector control methods. With the continued advancements in bioinformatics tools, we now have the capability to delve into various physiological processes in these insects. Here, we discuss the availability of multiple datasets describing the reproductive physiology of the common blood-feeding insects at the molecular level. Additionally, we compare the male-derived triggers transferred during mating to females, examining both shared and species-specific factors. These triggers initiate post-mating genetic responses in female vectors, affecting not only their reproductive success but also disease transmission.
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Affiliation(s)
- Aditi Kulkarni
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA; (A.K.); (F.M.D.); (S.G.); (B.I.G.)
- Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Frida M. Delgadillo
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA; (A.K.); (F.M.D.); (S.G.); (B.I.G.)
- Environmental Science and Engineering Ph.D. Program, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Sharan Gayathrinathan
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA; (A.K.); (F.M.D.); (S.G.); (B.I.G.)
- Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Brian I. Grajeda
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA; (A.K.); (F.M.D.); (S.G.); (B.I.G.)
- Biosciences Ph.D. Program, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Sourav Roy
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA; (A.K.); (F.M.D.); (S.G.); (B.I.G.)
- Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
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Castro VL, Paz D, Virrueta V, Estevao IL, Grajeda BI, Ellis CC, Quintana AM. Missense and nonsense mutations of the zebrafish hcfc1a gene result in contrasting mTor and radial glial phenotypes. Gene 2023; 864:147290. [PMID: 36804358 DOI: 10.1016/j.gene.2023.147290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/02/2023] [Accepted: 02/14/2023] [Indexed: 02/20/2023]
Abstract
Mutations in the HCFC1 transcriptional co-factor protein are the cause of cblX syndrome and X-linked intellectual disability (XLID). cblX is the more severe disorder associated with intractable epilepsy, abnormal cobalamin metabolism, facial dysmorphia, cortical gyral malformations, and intellectual disability. In vitro, murine Hcfc1 regulates neural precursor (NPCs) proliferation and number, which has been validated in zebrafish. However, conditional deletion of mouse Hcfc1 in Nkx2.1 + cells increased cell death, reduced Gfap expression, and reduced numbers of GABAergic neurons. Thus, the role of this gene in brain development is not completely understood. Recently, knock-in of both a cblX (HCFC1) and cblX-like (THAP11) allele were created in mice. Knock-in of the cblX-like allele was associated with increased expression of proteins required for ribosome biogenesis. However, the brain phenotypes were not comprehensively studied due to sub-viability. Therefore, a mechanism underlying increased ribosome biogenesis was not described. We used a missense, a nonsense, and two conditional zebrafish alleles to further elucidate this mechanism during brain development. We observed contrasting phenotypes at the level of Akt/mTor activation, the number of radial glial cells, and the expression of two downstream target genes of HCFC1, asxl1 and ywhab. Despite these divergent phenotypes, each allele studied demonstrates with a high degree of face validity when compared to the phenotypes reported in the literature. Collectively, these data suggest that individual mutations in the HCFC1 protein result in differential mTOR activity which may be associated with contrasting cellular phenotypes.
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Affiliation(s)
- Victoria L Castro
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA.
| | - David Paz
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA
| | - Valeria Virrueta
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA
| | - Igor L Estevao
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA
| | - Brian I Grajeda
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA
| | - Cameron C Ellis
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA
| | - Anita M Quintana
- Department of Biological Sciences, Border Biomedical Research Center, The University of Texas El Paso, El Paso, TX 79968, USA.
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Grajeda BI, De Chatterjee A, Villalobos CM, Pence BC, Ellis CC, Enriquez V, Roy S, Roychowdhury S, Neumann AK, Almeida IC, Patterson SE, Das S. Giardial lipid rafts share virulence factors with secreted vesicles and participate in parasitic infection in mice. Front Cell Infect Microbiol 2022; 12:974200. [PMID: 36081774 PMCID: PMC9445159 DOI: 10.3389/fcimb.2022.974200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Giardia lamblia, a protozoan parasite, is a major cause of waterborne infection, worldwide. While the trophozoite form of this parasite induces pathological symptoms in the gut, the cyst form transmits the infection. Since Giardia is a noninvasive parasite, the actual mechanism by which it causes disease remains elusive. We have previously reported that Giardia assembles cholesterol and GM1 glycosphingolipid-enriched lipid rafts (LRs) that participate in encystation and cyst production. To further delineate the role of LRs in pathogenesis, we isolated LRs from Giardia and subjected them to proteomic analysis. Various cellular proteins including potential virulence factors—e.g., giardins, variant surface proteins, arginine deaminases, elongation factors, ornithine carbomyltransferases, and high cysteine-rich membrane proteins—were found to be present in LRs. Since Giardia secretes virulence factors encapsulated in extracellular vesicles (EVs) that induce proinflammatory responses in hosts, EVs released by the parasite were isolated and subjected to nanoparticle tracking and proteomic analysis. Two types of EV—i.e., small vesicles (SVs; <100 nm, exosome-like particles) and large vesicles (LVs; 100–400 nm, microvesicle-like particles)—were identified and found to contain a diverse group of proteins including above potential virulence factors. Although pretreatment of the parasite with two giardial lipid raft (gLR) disruptors, nystatin (27 μM) and oseltamivir (20 μM), altered the expression profiles of virulence factors in LVs and SVs, the effects were more robust in the case of SVs. To examine the potential role of rafts and vesicles in pathogenicity, Giardia-infected mice were treated with oseltamivir (1.5 and 3.0 mg/kg), and the shedding of cysts were monitored. We observed that this drug significantly reduced the parasite load in mice. Taken together, our results suggest that virulence factors partitioning in gLRs, released into the extracellular milieu via SVs and LVs, participate in spread of giardiasis and could be targeted for future drug development.
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Affiliation(s)
- Brian I. Grajeda
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Atasi De Chatterjee
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Carmen M. Villalobos
- Department of Pathology, School of Medicine, University of New Mexico, Albuquerque, NM, United States
| | - Breanna C. Pence
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Cameron C. Ellis
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Vanessa Enriquez
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Sourav Roy
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Sukla Roychowdhury
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Aaron K. Neumann
- Department of Pathology, School of Medicine, University of New Mexico, Albuquerque, NM, United States
| | - Igor C. Almeida
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
| | - Steven E. Patterson
- Center for Drug Design, University of Minnesota, Minneapolis, MN, United States
| | - Siddhartha Das
- Infectious Disease and Immunology, Border Biomedical Research Center and the Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, United States
- *Correspondence: Siddhartha Das,
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Aguilera J, Karki CB, Li L, Vazquez Reyes S, Estevao I, Grajeda BI, Zhang Q, Arico CD, Ouellet H, Sun J. Nα-Acetylation of the virulence factor EsxA is required for mycobacterial cytosolic translocation and virulence. J Biol Chem 2020; 295:5785-5794. [PMID: 32169899 PMCID: PMC7186180 DOI: 10.1074/jbc.ra119.012497] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 03/11/2020] [Indexed: 12/23/2022] Open
Abstract
The Mycobacterium tuberculosis virulence factor EsxA and its chaperone EsxB are secreted as a heterodimer (EsxA:B) and are crucial for mycobacterial escape from phagosomes and cytosolic translocation. Current findings support the idea that for EsxA to interact with host membranes, EsxA must dissociate from EsxB at low pH. However, the molecular mechanism by which the EsxA:B heterodimer separates is not clear. In the present study, using liposome-leakage and cytotoxicity assays, LC-MS/MS-based proteomics, and CCF-4 FRET analysis, we obtained evidence that the Nα-acetylation of the Thr-2 residue on EsxA, a post-translational modification that is present in mycobacteria but absent in Escherichia coli, is required for the EsxA:B separation. Substitutions at Thr-2 that precluded Nα-acetylation inhibited the heterodimer separation and hence prevented EsxA from interacting with the host membrane, resulting in attenuated mycobacterial cytosolic translocation and virulence. Molecular dynamics simulations revealed that at low pH, the Nα-acetylated Thr-2 makes direct and frequent "bind-and-release" contacts with EsxB, which generates a force that pulls EsxB away from EsxA. In summary, our findings provide evidence that the Nα-acetylation at Thr-2 of EsxA facilitates dissociation of the EsxA:B heterodimer required for EsxA membrane permeabilization and mycobacterial cytosolic translocation and virulence.
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Affiliation(s)
- Javier Aguilera
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Chitra B Karki
- Department of Physics, University of Texas at El Paso, El Paso, Texas 79968
| | - Lin Li
- Department of Physics, University of Texas at El Paso, El Paso, Texas 79968
| | - Salvador Vazquez Reyes
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Igor Estevao
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Brian I Grajeda
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Qi Zhang
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Chenoa D Arico
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Hugues Ouellet
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968
| | - Jianjun Sun
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968; Border Biomedical Research Center, University of Texas at El Paso, El Paso, Texas 79968.
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Duarte TT, Ellis CC, Grajeda BI, De Chatterjee A, Almeida IC, Das S. A Targeted Mass Spectrometric Analysis Reveals the Presence of a Reduced but Dynamic Sphingolipid Metabolic Pathway in an Ancient Protozoan, Giardia lamblia. Front Cell Infect Microbiol 2019; 9:245. [PMID: 31396488 PMCID: PMC6668603 DOI: 10.3389/fcimb.2019.00245] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 06/24/2019] [Indexed: 12/11/2022] Open
Abstract
Giardia lamblia, a single-celled eukaryote, colonizes and thrives in the small intestine of humans. Because of its compact and reduced genome, Giardia has adapted a “minimalistic” life style, as it becomes dependent on available resources of the small intestine. Because Giardia expresses fewer sphingolipid (SL) genes—and glycosphingolipids are critical for encystation—we investigated the SL metabolic cycle in this parasite. A tandem mass spectrometry (MS/MS) analysis reveals that major SLs in Giardia include sphingomyelins, sphingoid bases, ceramides, and glycosylceramides. Many of these lipids are obtained by Giardia from the growth medium, remodeled at their fatty acyl chains and end up in the spent medium. For instance, ceramide-1-phosphate, a proinflammatory molecule that is not present in the culture medium, is generated from sphingosine (abundant in the culture medium) possibly by remodeling reactions. It is then subsequently released into the spent medium. Thus, the secretion of ceramide-1-phospate and other SL derivatives by Giardia could be associated with inflammatory bowel disease observed in acute giardiasis. Additionally, we found that the levels of SLs increase in encysting Giardia and are differentially regulated throughout the encystation cycle. We propose that SL metabolism is important for this parasite and, could serve as potential targets for developing novel anti-giardial agents.
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Affiliation(s)
- Trevor T Duarte
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Cameron C Ellis
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Brian I Grajeda
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Atasi De Chatterjee
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Igor C Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States.,Infectious Disease and Immunology Cluster, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Siddhartha Das
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States.,Infectious Disease and Immunology Cluster, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
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