bims-polyam 2023-11-05 papers

Issue of 2023–11–05
three papers selected by
Sebastian J. Hofer, University of Graz

Sci Rep. 2023 Oct 31. 13(1): 18714

Effects of slight shading in summer on the leaf senescence and endogenous hormone and polyamine contents in herbaceous peony.

Anqi Xie, Mengwen Lv, Dongliang Zhang, Yajie Shi, Lijin Yang, Xiao Yang, Jie Du, Limin Sun, Xia Sun.

Herbaceous peony is a perennial root plant that likes light and is cold-resistant. During summer, high temperature and strong light intensity advance its entry into the leaf wilting stage, which limits the accumulation of nutrients and formation of strong buds and severely affects its growth and development the following year. In this study, the wild herbaceous peony species and two main cultivars, 'Zifengyu' and 'Hongfengyu', were subjected to slight shading and strong light environments in summer, and their effects on leaf senescence and endogenous hormone and polyamine contents were explored. Slight shading treatment significantly delayed withering, increased the leaf net photosynthetic rate, and increased the chlorophyll, soluble sugar, indole-3-acetic acid, zeatin, gibberellin, spermine, spermidine, putrescine, and polyamine contents. Additionally, slight shading significantly reduced the proline and abscisic acid contents. Slight shading during summer prolonged the green period and delayed leaf senescence. The tolerance of tested materials to strong light intensity in summer was ranked as follows: 'Zifengyu' > 'Hongfengyu' > wild species. In conclusion, this study revealed that summer leaf senescence is delayed in herbaceous peony through shading and growth regulators. Additional varieties should be evaluated to provide reference for high-efficiency, high-quality, and high-yield cultivation of herbaceous peony.

DOI: https://doi.org/10.1038/s41598-023-46192-y

Cell Rep Med. 2023 Oct 24. pii: S2666-3791(23)00438-X. [Epub ahead of print] 101261

Inhibition of polyamine biosynthesis preserves β cell function in type 1 diabetes.

In preclinical models, α-difluoromethylornithine (DFMO), an ornithine decarboxylase (ODC) inhibitor, delays the onset of type 1 diabetes (T1D) by reducing β cell stress. However, the mechanism of DFMO action and its human tolerability remain unclear. In this study, we show that mice with β cell ODC deletion are protected against toxin-induced diabetes, suggesting a cell-autonomous role of ODC during β cell stress. In a randomized controlled trial (ClinicalTrials.gov: NCT02384889) involving 41 recent-onset T1D subjects (3:1 drug:placebo) over a 3-month treatment period with a 3-month follow-up, DFMO (125-1,000 mg/m2) is shown to meet its primary outcome of safety and tolerability. DFMO dose-dependently reduces urinary putrescine levels and, at higher doses, preserves C-peptide area under the curve without apparent immunomodulation. Transcriptomics and proteomics of DFMO-treated human islets exposed to cytokine stress reveal alterations in mRNA translation, nascent protein transport, and protein secretion. These findings suggest that DFMO may preserve β cell function in T1D through islet cell-autonomous effects.

Keywords: disease modification; islet; ornithine decarboxylase; polyamines; prevention; trial; type 1 diabetes; α-difluoromethylornithine; β cell; β cell stress

DOI: https://doi.org/10.1016/j.xcrm.2023.101261

Front Biosci (Landmark Ed). 2023 Oct 20. 28(10): 251

Serum Metabolomic Profile in Hypoxia-Induced Pulmonary Hypertension Mice after C75 Treatment.

Shun Chen, Shujia Lin, Wei Liu, Qiuping Lin, Yi Yang, Qingzhu Qiu, Yanfang Zong, Tingting Xiao, Cuilan Hou, Lijian Xie.

BACKGROUND: Inhibition of fatty acid synthase (FAS) plays a crucial protective role in pulmonary hypertension (PH). Our aim was to identify novel metabolites in mice with hypoxia-induced PH after treatment with C75 (FAS inhibitor) and to confirm the presence of these metabolites in paediatric patients with PH.
METHODS: The PH mouse model was built by chronic hypoxia and ovalbumin (OVA) assistance. Untargeted metabolomics was used to analyse mouse serum. Six children with PH and six relative controls (patients without lung and heart disease) were selected in Shanghai Children's Hospital and they all performed blood tandem mass spectrometry during hospitalization.
RESULTS: First, a total of 29 differential metabolites, including lipid metabolites, polyamine, and glutamine were identified as differential metabolites in the hypoxia group compared with the control group. After C75 treatment, symptoms were partially relieved in the PH mouse, and 15 differential metabolites, including lipid metabolites, polyamine, and glutamine were identified in the hypoxia + C75 group compared with the hypoxia group. These differential metabolites were enriched in arginine and glycerolipid metabolism through metabolite set enrichment analyses and were involved in excessive cell proliferation, which was a characteristic of PH. Second, glutamine and caproyl carnitine levels were increased in paediatric patients with PH.
CONCLUSIONS: FAS may be a potential PH therapeutic target. Lipid metabolites, polyamine, and glutamine, are closely related to PH. Putrescine and glutamine might be biomarkers for PH.

Keywords: C75; biomarkers; metabolomics; pulmonary hypertension

DOI: https://doi.org/10.31083/j.fbl2810251