scholarly journals Comparison of the Effects of Nonprotein and Protein Nitrogen on Apoptosis and Autophagy of Rumen Epithelial Cells in Goats

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2079
Author(s):  
Zhiwei Kong ◽  
Chuanshe Zhou ◽  
Jinhe Kang ◽  
Zhiliang Tan
Keyword(s):  
Epithelial Cells ◽  
Protein Expression ◽  
Caspase 3 ◽  
Critical Role ◽  
Nitrogen Sources ◽  
The Self ◽  
Nonprotein Nitrogen ◽  
Protein Nitrogen ◽  
Self Renewal ◽  
Ameliorative Effect

Protein nutrition is particularly important for the self-renewal processes of gastrointestinal epithelial cells. The self-renewal of cells is inseparable from the interaction between apoptosis and autophagy. However, there are few reports on the relationship between different nitrogen sources and apoptosis/autophagy. In this study, the relative protein expression of Bcl-2-associated X protein(Bax), caspase-3, and p62 was significantly higher (p < 0.05), while that of Bcl-xl, Bcl-2, Beclin1, and Microtuble-associated protein light chain 3 (LC3-II) was significantly lower (p < 0.05), in the NH4Cl group in comparison with the NH4Cl + 4-phenylbutyric acid (4PBA) group. In addition, the relative protein expression of Bax and caspase-3 was significantly higher (p < 0.05), while that of Bcl-2 and Bcl-xl was decreased significantly (p < 0.05), in the NH4Cl + 3-Methyladenine (3-MA) group and the methionine (Met) + 3-MA group in comparison with the NH4Cl group. Furthermore, the relative protein expression of Beclin1 and LC3B-II was significantly lower (p < 0.05), while that of p62 was significantly higher (p < 0.05), in the NH4Cl + Z-VAD-FMK group and the Met + Z-VAD-FMK group in comparison with the NH4Cl group. In conclusion, our results suggested that endoplasmic reticulum (ER) stress played a critical role in the crosstalk between apoptosis and autophagy induced by NH4Cl and Met. Autophagy had a more obvious ameliorative effect on ruminal epithelial cell apoptosis after treatment with nonprotein nitrogen than after treatment with protein nitrogen. These findings may reveal the molecular mechanism of apoptosis and autophagy induced by nonprotein nitrogen and protein nitrogen.

Metabolic Regulation and Related Molecular Mechanisms in Various Stem Cell Functions

2020 ◽  
Vol 15 (6) ◽  
pp. 531-546 ◽  
Author(s):  
Hwa-Yong Lee ◽  
In-Sun Hong
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Oxidative Phosphorylation ◽  
Metabolic Pathways ◽  
Critical Role ◽  
The Self ◽  
Specific Cell ◽  
Differentiation Potential ◽  
Self Renewal ◽  
Cell Functions

Recent studies on the mechanisms that link metabolic changes with stem cell fate have deepened our understanding of how specific metabolic pathways can regulate various stem cell functions during the development of an organism. Although it was originally thought to be merely a consequence of the specific cell state, metabolism is currently known to play a critical role in regulating the self-renewal capacity, differentiation potential, and quiescence of stem cells. Many studies in recent years have revealed that metabolic pathways regulate various stem cell behaviors (e.g., selfrenewal, migration, and differentiation) by modulating energy production through glycolysis or oxidative phosphorylation and by regulating the generation of metabolites, which can modulate multiple signaling pathways. Therefore, a more comprehensive understanding of stem cell metabolism could allow us to establish optimal culture conditions and differentiation methods that would increase stem cell expansion and function for cell-based therapies. However, little is known about how metabolic pathways regulate various stem cell functions. In this context, we review the current advances in metabolic research that have revealed functional roles for mitochondrial oxidative phosphorylation, anaerobic glycolysis, and oxidative stress during the self-renewal, differentiation and aging of various adult stem cell types. These approaches could provide novel strategies for the development of metabolic or pharmacological therapies to promote the regenerative potential of stem cells and subsequently promote their therapeutic utility.

LPA protects intestinal epithelial cells from apoptosis by inhibiting the mitochondrial pathway

2003 ◽  
Vol 284 (5) ◽  
pp. G821-G829 ◽  
Author(s):  
Wenlin Deng ◽  
De-An Wang ◽  
Elvira Gosmanova ◽  
Leonard R. Johnson ◽  
Gabor Tigyi
Keyword(s):  
Epithelial Cells ◽  
Cytochrome C ◽  
Protein Expression ◽  
Caspase 3 ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial ◽  
Caspase 9 ◽  
Cytochrome C Release ◽  
Apoptotic Pathway ◽  
Antiapoptotic Activity

We previously showed ( Gastroenterology 123: 206–216, 2002) that lysophosphatidic acid (LPA) protects and rescues rat intestinal epithelial cells (IEC-6) from apoptosis. Here, we provide evidence for the LPA-elicited inhibition of the mitochondrial apoptotic pathway leading to attenuation of caspase-3 activation. Pretreatment of IEC-6 cells with LPA inhibited campothecin-induced caspase-9 and caspase-3 activation and DNA fragmentation. A caspase-9 inhibitor peptide mimicked the LPA-elicited antiapoptotic activity. LPA elicited ERK1/ERK2 and PKB/Akt phosphorylation. The LPA-elicited antiapoptotic activity and inhibition of caspase-9 activity were abrogated by pertussis toxin, PD 98059, wortmannin, and LY 294002. LPA reduced cytochrome c release from mitochondria and prevented activation of caspase-9. LPA prevented translocation of Bax from cytosol to mitochondria and increased the expression of the antiapoptotic Bcl-2 mRNA and protein. LPA had no effect on Bcl-xl, Bad, and Bak mRNA or protein expression. These data indicate that LPA protects IEC-6 cells from camptothecin-induced apoptosis through Gi-coupled inhibition of caspase-3 activation mediated by the attenuation of caspase-9 activation due to diminished cytochrome c release, involving upregulation of Bcl-2 protein expression and prevention of Bax translocation.

scholarly journals SIX1 Is a Novel Effector Gene in CALM-AF10 Leukemia

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5035-5035
Author(s):  
Waitman K. Aumann ◽  
Catherine P. Lavau ◽  
Amanda Harrington ◽  
Amanda E. Conway ◽  
Daniel S. Wechsler
Keyword(s):  
Nuclear Export ◽  
Conflicts Of Interest ◽  
Fetal Liver ◽  
Critical Role ◽  
Leukemia Cell ◽  
The Self ◽  
Hek293 Cells ◽  
Hematopoietic Progenitors ◽  
Self Renewal ◽  
Hoxa Genes

Background: The CALM-AF10 translocation is detected in ~10% of T-cell acute lymphoblastic leukemias (T-ALLs), and in some acute myeloid leukemias (AMLs). CALM-AF10 leukemias are characterized by high expression of proleukemic HOXA genes, which serve a critical role in hematopoiesis. We hypothesized that identification of novel CALM-AF10 effector genes may yield new therapeutic targets in this difficult to treat leukemia. We took advantage of our prior observation that the nuclear export factor CRM1/XPO1 tethers CALM-AF10 to HOXA genes by interacting with a nuclear export signal (NES) in CALM. Using next generation sequencing, we determined that, SIX1, similar to HOXA genes, is increased in CALM-AF10 leukemias and decreased in response to CRM1 inhibition with Leptomycin B (LMB). Design/Methods: RT-qPCR and Chromatin Immunoprecipitation were performed using both bone marrow progenitors and murine embryonic fibroblasts (MEFs) transduced with CALM-AF10 or an empty vector, with and without LMB. The ability of SIX1 to enhance self-renewal of hematopoietic progenitors was examined by measuring the colony-forming ability of transduced fetal liver hematopoietic progenitor cells. CRISPR-Cas9 was used to silence SIX1 in Human Embryonic Kidney 293 (HEK293) cells. Results: RT-qPCR confirmed overexpression of SIX1 in both CALM-AF10 transduced MEFs and CALM-AF10 leukemias, with decreased SIX1 expression observed in the presence of LMB. ChIP analysis showed that CALM-AF10 binds to the SIX1 gene locus. Overexpression of SIX1 in fetal liver cells was sufficient to increase the self-renewal potential of colony-forming progenitors. SIX1 was successfully knocked out in HEK293 cells without a significant effect on HEK293 proliferation. Conclusions: The SIX1 homeobox gene is highly expressed during development and its expression is silenced post-embryogenesis. Increased SIX1 expression has been reported in numerous solid tumors. We have determined that SIX1 is upregulated in CALM-AF10 leukemias, and increases the self-renewal potential of hematopoietic progenitors. Using CRISPR-Cas9 to silence SIX1, we have demonstrated that SIX1 is not essential for cell survival, and that its inhibition may impair CALM-AF10 leukemia cell proliferation. Thus, SIX1 may play a pathogenic role in leukemogenesis and is a potential therapeutic target in CALM-AF10 leukemias. Disclosures No relevant conflicts of interest to declare.

scholarly journals In vitro evaluation of nutritional quality of ensiled rice offal enhanced with nonprotein nitrogen sources and soybean meal residue

2019 ◽  
Vol 46 (1) ◽  
pp. 236-245
Author(s):  
A. Y. Abdullahi ◽  
A. S. Muhammad ◽  
M. H. Zango ◽  
S. Madaki ◽  
M. A. Dambatta ◽  
...  
Keyword(s):  
Soybean Meal ◽  
Energy Content ◽  
Poultry Litter ◽  
Nitrogen Sources ◽  
Nonprotein Nitrogen ◽  
Protein Nitrogen ◽  
Randomized Design ◽  
Completely Randomized Design

An experiment was conducted to assess the appearance, smell, texture, pH, temperature, chemical composition and energy content of ensiled Rice offal (RO) treated with non-protein nitrogen sources and soybean meal residue in a completely randomized design. Rice offal was treated with different proportions of Urea, Poultry litter (PL) and Soybean meal residue (SBMR) and ensiled. The treatment combinations were; A (100%RO), B (100%RO + Urea), C (75%RO + 25%PL), D (50%RO + 50%PL), E (75%RO + 25%SBMR) and F (50%RO + 50%SBMR). The treatments were ensiled for 21 days in triplicates. The results showed that silages were adequately fermented with sweet aroma. The silages were acidic (4.70 – 5.80) except for treatments C and D which had pH of 7.20 and 7.00, respectively. The temperatures of the silages were significantly (P<0.05) different. The proximate composition of silages differed significantly (P<0.05), being highest for %CP, %EE and ash in treatment B. Dry matter contents were also significantly different (P<0.05) with treatment A having the highest (90.25%). Rice offal and Urea mixtures resulted in silages with highest NDF, HEM and Energy. Lowest NDF was obtained in treatment without additive (Treatment A) compared to all other treatments. Least ADF was obtained in Treatment E (75% RO + 25% SBMR). Enhancement of rice offal with urea, poultry litter and soybean meal residue has shown improvement in the silage physiochemical quality

scholarly journals A genome-scale CRISPR screen reveals factors regulating Wnt-dependent renewal of mouse gastric epithelial cells

2021 ◽  
Vol 118 (4) ◽  
pp. e2016806118
Author(s):  
Kazuhiro Murakami ◽  
Yumi Terakado ◽  
Kikue Saito ◽  
Yoshie Jomen ◽  
Haruna Takeda ◽  
...  
Keyword(s):  
Stem Cell ◽  
Epithelial Cells ◽  
Adult Stem Cells ◽  
Ex Vivo ◽  
Critical Role ◽  
Gastric Epithelial Cells ◽  
Screening Assay ◽  
Self Renewal ◽  
A Genome ◽  
Genome Scale

An ability to safely harness the powerful regenerative potential of adult stem cells for clinical applications is critically dependent on a comprehensive understanding of the underlying mechanisms regulating their activity. Epithelial organoid cultures accurately recapitulate many features of in vivo stem cell-driven epithelial renewal, providing an excellent ex vivo platform for interrogation of key regulatory mechanisms. Here, we employed a genome-scale clustered, regularly interspaced, short palindromic repeats (CRISPR) knockout (KO) screening assay using mouse gastric epithelial organoids to identify modulators of Wnt-driven stem cell-dependent epithelial renewal in the gastric mucosa. In addition to known Wnt pathway regulators, such as Apc, we found that KO of Alk, Bclaf3, or Prkra supports the Wnt independent self-renewal of gastric epithelial cells ex vivo. In adult mice, expression of these factors is predominantly restricted to non-Lgr5–expressing stem cell zones above the gland base, implicating a critical role for these factors in suppressing self-renewal or promoting differentiation of gastric epithelia. Notably, we found that Alk inhibits Wnt signaling by phosphorylating the tyrosine of Gsk3β, while Bclaf3 and Prkra suppress regenerating islet-derived (Reg) genes by regulating the expression of epithelial interleukins. Therefore, Alk, Bclaf3, and Prkra may suppress stemness/proliferation and function as novel regulators of gastric epithelial differentiation.

A critical role for Smad4 in the self-renewal of hematopoietic stem cells

2008 ◽  
Vol 40 (2) ◽  
pp. 271
Author(s):  
Göran Karlsson ◽  
Ulrika Blank ◽  
Jennifer L Moody ◽  
Sofie Singbrant ◽  
Stefan Karlsson
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Critical Role ◽  
The Self ◽  
Self Renewal ◽  
Hematopoietic Stem

Telomerase Promotes the Self-Renewal of Human Hematopoietic Progenitor Cells but Does Not Maintain Telomere Length.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 647-647 ◽  
Author(s):  
Junping Wei ◽  
Mark Wunderlich ◽  
James C. Mulloy
Keyword(s):  
Telomere Length ◽  
Progenitor Cells ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Telomerase Activity ◽  
The Self ◽  
Hematopoietic Progenitor Cells ◽  
Hematopoietic Progenitor ◽  
Self Renewal ◽  
Hematopoietic Stem

Abstract Telomerase is a reverse transcriptase that adds telomeric sequences onto chromosome ends. During hematopoiesis, telomerase activity is high in proliferating hematopoietic stem and progenitor cells, but decreases sharply as cells differentiate. Approximately 90% of all human cancers are telomerase positive, including samples from AML patients. To understand the role of telomerase in human hematopoietic stem and progenitor cell proliferation and differentiation, and in the development of leukemia, we established stable long-term cultures expressing high levels of telomerase by retrovirus-mediated transduction of the h-TERT (catalytic subunit of telomerase) gene into AML1-ETO-expressing CD34+ (AE) cells. We have previously shown that these AE cells maintain CD34 expression and proliferate for 7 months in culture but gradually lose telomere length and are not immortal, providing a good model for studying the molecular mechanisms involved in telomere shortening. Strikingly, telomerase expression enhanced the self-renewal ability of the human hematopoietic progenitor cells, as shown by continuous replating ability in methylcellulose assays. We also detected a pronounced delay in the differentiation of the progenitor cells upon telomerase expression, and an expansion of the progenitor pool. Telomerase expression promoted proliferation due to increased cell cycle progression as well as a survival advantage. At the same time, these cells demonstrated a progressive decline in telomere length, despite telomerase activity equivalent to that detected in leukemia cell lines. We conclude that expression of hTERT expands the pool of hematopoietic progenitors but does not maintain long telomeres in human CD34+ cells. hTERT plays a critical role not only in telomere homeostasis for genetic stability but also in cellular proliferation, differentiation, and self-renewal, functions that may be part of hTERT involvement in leukemogenesis. These data open an important debate regarding the specific contribution of telomerase expression to the leukemic phenotype and the potential timing of this essential hit in the progression of the disease.

scholarly journals Circular RNA circIPO11 drives self-renewal of liver cancer initiating cells via Hedgehog signaling

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Yang Gu ◽  
Yanying Wang ◽  
Luyun He ◽  
Jiahang Zhang ◽  
Xiaoxiao Zhu ◽  
...  
Keyword(s):  
Liver Cancer ◽  
Signaling Pathway ◽  
Hedgehog Signaling ◽  
Critical Role ◽  
Circular Rna ◽  
The Self ◽  
High Rate ◽  
Hedgehog Signaling Pathway ◽  
Self Renewal ◽  
Tumor Tissues

Abstract Background Hepatocellular carcinoma (HCC) is one of the most intractable tumors in the world due to its high rate of recurrence and heterogeneity. Liver cancer initiating cells also called cancer stem cells (CSCs) play a critical role in resistance against typical therapy and high tumor-initiating potential. However, the role of the novel circular RNA (circRNA) circIPO11 in the maintenance of liver cancer initiating cells remains elusive. Methods CircRNAs highly conserved in humans and mice were identified from 3 primary HCC samples by circRNA array. The expression and function of circIPO11 were further evaluated by Northern blot, limiting dilution xenograft analysis, chromatin isolation by RNA purification-PCR assay (ChIRP) and HCC patient-derived tumor cells (PDC) models. CircIpo11 knockout (KO) mice were generated by a CRISPR/Cas9 technology. Results CircIPO11 is highly expressed in HCC tumor tissues and liver CSCs. CircIPO11 is required for the self-renewal maintenance of liver CSCs to initiate HCC development. Mechanistically, circIPO11 recruits TOP1 to GLI1 promoter to trigger its transcription, leading to the activation of Hedgehog signaling. Moreover, GLI1 is also highly expressed in HCC tumor tissues and liver CSCs, and TOP1 expression levels positively correlate with the metastasis, recurrence and survival of HCC patients. Additionally, circIPO11 knockout in mice suppresses the progression of chemically induced liver cancer development. Conclusion Our findings reveal that circIPO11 drives the self-renewal of liver CSCs and promotes the propagation of HCC via activating Hedgehog signaling pathway. Antisense oligonucleotides (ASOs) against circIPO11 combined with TOP1 inhibitor camptothecin (CPT) exert synergistic antitumor effect. Therefore, circIPO11 and the Hedgehog signaling pathway may provide new potential targets for the treatment of HCC patients.

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