Hydrogen sulfide (H
2
S) and methylglyoxal (MG) were supposed to be novel signaling molecules in plants. However, whether interplay between H
2
S and MG can initiate thermotolerance in maize ...seedlings and in relation to metabolism of reactive oxygen species (ROS) and osmolytes is little known. In this study, watering with MG and NaHS (H
2
S donor) alone or in combination elevated survival and tissue vigor of maize seedlings under heat stress and coped with an increase in the biomembrane injury (as indicated in membrane lipid peroxidation and electrolyte leakage). The above-mentioned effects were separately weakened by MG scavengers (N-acetyl cysteine: NAC; aminoguanidine: AG) and H
2
S inhibitor (DL-propargylglycine, PAG) and scavenger (hypotaurine, HT). These suggested that the interplay between H
2
S and MG initiated the thermotolerance in maize seedlings. The further data indicated that, under non-heat stress and heat stress conditions, MG and NaHS alone or in combination modulated ROS metabolism by regulating the activities of antioxidant enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase, monodehydroascorbate reductase, and dehydroascorbate reductase) and the contents of non-enzymatic antioxidants (ascorbic acid, glutathione, flavonoids, and carotenoids) in maize seedlings. In addition, MG and NaHS alone or in combination also separately modulated the metabolism of osmolytes (proline, trehalose, glycine betaine, and total soluble sugar), H
2
S (L-cysteine desulfhydrase and O-acetylserine (thione) lyase), and MG (glyoxalase I, glyoxalase II, and MG reductase). These physiological effects also were separately impaired by NAC, AG, PAG, and HT. The current data illustrated that the interplay between H
2
S and MG initiated the thermotolerance in maize seedlings by modulating ROS, osmolyte, H
2
S, and MG metabolism.
Polypodiales suborder Dennstaedtiineae contain a single family Dennstaedtiaceae, eleven genera, and about 270 species, and include some groups that were previously placed in Dennstaedtiaceae, ...Hypolepidaceae, Monachosoraceae, and Pteridaceae. The classification and phylogenetic relationships among these eleven genera have been poorly understood. To explore the deep relationships within suborder Dennstaedtiineae and estimate the early diversification of this morphologically heterogeneous group, we analyzed complete plastomes of 57 samples representing all eleven genera of suborder Dennstaedtiineae using maximum likelihood and Bayesian inference. The phylogenetic relationships of all the lineages in the bracken fern family Dennstaedtiaceae were well resolved with strong support values. All six genera of Hypolepidoideae were recovered as forming a monophyletic group with full support, and Pteridium was fully supported as sister to all the other genera in Hypolepidoideae. Dennstaedtioideae (Dennstaedtia s.l.) fell into four clades with full support: the Microlepia clade, the northern Dennstaedtia clade, the Dennstaedtia globulifera clade, and the Dennstaedtia s.s. clade. Monachosorum was strongly resolved as sister to all the remaining genera of suborder Dennstaedtiineae. Based on the well resolved relationships among genera, the divergence between Monachosorum and other groups of suborder Dennstaedtiineae was estimated to have occurred in the Early Cretaceous, and all extant genera (and clades) in Dennstaedtiineae, were inferred to have diversified since the Late Oligocene. This study supports reinstating a previously published family Monachosoraceae as a segregate from Dennstaedtiaceae, based on unique morphological evidence, the shady habitat, and the deep evolutionary divergence from its closest relatives.
As a programmed cell death 1 (PD-1) inhibitor, camrelizumab is used in the treatment of a variety of malignancies. However, a variety of immune-mediated adverse reactions have been reported in a wide ...range of clinical applications, including immune-related colitis, arthritis, hepatitis, etc.
This 56-year-old male patient experienced diarrhea, bloody stool, and knee pain after receiving camrelizumab for metastatic esophageal squamous cell carcinoma. Colonoscopy showed granular changes in the whole colonic mucosa and blurred or even disappeared vascular texture. Pathology showed chronic inflammation of the colonic mucosa. Magnetic resonance imaging of knee joint showed exudative inflammatory changes in bilateral knee joints.
Immune checkpoint inhibitor-induced colitis and arthritis.
Mesalazine oral (extended-release granules, 1000 mg/quarter in die daily). Dexamethasone sodium phosphate (once daily, 5mg in the evening) and compound cypress liquid (once daily, 100ml in the evening) were given by enema. Anti-inflammatory and analgesic treatment of bone pain plaster.
The patient had diarrhea reduced to 3 times/day, no more bloody stools, and the knee pain was relieved.
This article describes the cases of immune-related colitis and arthritis caused by camrelizumab, and recommends considering the risk of colitis and arthritis with camrelizumab monotherapy or combination therapy.
RING-finger-type ubiquitin E3 ligase Constitutively Photomorphogenic 1 (COP1) and floral integrators such as FLOWERING LOCUS T (FT), TWIN SISTER OF FT (TSF) and SUPPRESSOR OF OVEREXPRESSION OF ...CONSTANS1 (SOC1) have been identified as regulators of stomatal movement. However, little is known about their roles and relationship in dark-induced stomatal closure. Here, we demonstrated that COP1 is required for dark-induced stomatal closure using
mutant. The
mutant closed stomata in response to exogenous nitric oxide (NO) but not hydrogen peroxide (H
O
), and H
O
but not NO accumulated in
in darkness, further indicating that COP1 acts downstream of H
O
and upstream of NO in dark-induced stomatal closure. Expression of
,
and
in wild-type (WT) plants decreased significantly with dark duration time, but this process was blocked in
. Furthermore,
,
, and
mutants accumulated NO and closed stomata faster than WT plants in response to darkness. Altogether, our results indicate that COP1 transduces H
O
signaling, promotes NO accumulation in guard cells by suppressing
,
and
expression, and consequently leads to stomatal closure in darkness. These findings add new insights into the mechanisms of dark-induced stomatal closure.
The tyrosine phosphorylation barcode encoded in C-terminus of HER2 and its ubiquitination regulate diverse HER2 functions. PTPN18 was reported as a HER2 phosphatase; however, the exact mechanism by ...which it defines HER2 signaling is not fully understood. Here, we demonstrate that PTPN18 regulates HER2-mediated cellular functions through defining both its phosphorylation and ubiquitination barcodes. Enzymologic characterization and three crystal structures of PTPN18 in complex with HER2 phospho-peptides revealed the molecular basis for the recogni- tion between PTPN18 and specific HER2 phosphorylation sites, which assumes two distinct conformations. Unique structural properties of PTPN18 contribute to the regulation of sub-cellular phosphorylation networks downstream of HER2, which are required for inhibition of HER2-mediated cell growth and migration. Whereas the catalytic domain of PTPN18 blocks lysosomal routing and delays the degradation of HER2 by dephosphorylation of HER2 on py111z, the PEST domain of PTPN18 promotes K48-1inked HER2 ubiquitination and its rapid destruction via the proteasome pathway and an HER2 negative feedback loop. In agreement with the negative regulatory role of PTPN18 in HER2 signaling, the HER2/PTPN18 ratio was correlated with breast cancer stage. Taken together, our study presents a structural basis for selective HER2 dephosphorylation, a previously uncharacterized mechanism for HER2 degradation and a novel function for the PTPN18 PEST domain. The new regulatory role of the PEST domain in the ubiquitination pathway will broaden our understanding of the functions of other important PEST domain-containing phosphatases, such as LYP and PTPN12.
More and more evidence shows that metabolic reprogramming is closely related to the occurrence of AD. The metabolic conversion of oxidative phosphorylation into glycolysis will aggravate ...microglia-mediated inflammation. It has been demonstrated that baicalein could inhibit neuroinflammation in LPS-treated BV-2 microglial cells, but whether the anti-neuroinflammatory mechanisms of baicalein were related to glycolysis is unclear. Our results depicted that baicalein significantly inhibited the levels of nitric oxide (NO), interleukin-6 (IL-6), prostaglandin 2 (PGE2) and tumor necrosis factor (TNF-α) in LPS-treated BV-2 cells.
1
H-NMR metabolomics analysis showed that baicalein decreased the levels of lactic acid and pyruvate, and significantly regulated glycolytic pathway. Further study revealed that baicalein significantly inhibited the activities of glycolysis-related enzymes including hexokinase (HK), 6-phosphate kinase (6-PFK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and inhibited STAT3 phosphorylation and c-Myc expression. By using of STAT3 activator RO8191, we found that baicalein suppressed the increase of STAT3 phosphorylation and c-Myc expression triggered by RO8191, and inhibited the increased levels of 6-PFK, PK and LDH caused by RO8191. In conclusion, these results suggested that baicalein attenuated the neuroinflammation in LPS-treated BV-2 cells by inhibiting glycolysis through STAT3/c-Myc pathway.
Ischemic preconditioned (IP) neurons protect astrocytes against ischemia/reperfusion (I/R)‐induced injury by inhibiting oxidative stress. However, the relevant mechanisms are unknown. Based on the ...role of nuclear factor‐κB (NF‐κB) in cell survival and adaption to oxidative stress, we hypothesized that NF‐κB might be associated with astroprotection induced by IP neurons via upregulation of antioxidant enzymes. Here, we investigated the effects of IP neurons on NF‐κB activation, cell viability, reactive oxygen species (ROS), expression of antioxidant enzymes, erythropoietin (EPO), and tumor necrosis factor α (TNF‐α), in the presence or absence of BAY11‐7082 (an NF‐κB inhibitor), anti‐EPO, and anti‐TNF‐α antibodies, in astrocytes treated with or without I/R. We found that IP neurons could keep NF‐κB activation at a relatively higher but beneficial level, and in turn, upregulated the activity of antioxidant enzymes and hence enhanced cell viability and reduced ROS in I/R treated astrocytes. The results collectively indicated that IP neurons are able to significantly inhibit the I/R‐induced NF‐κB overactivation, probably via EPO and TNF‐α, being essential for IP neuron‐induced astroprotection under the conditions of I/R. We concluded that NF‐κB‐mediated antioxidative stress is one of the mechanisms by which IP neurons protect astrocytes against I/R injury.
Our results collectively indicated that IP neurons are able to significantly inhibit the ischemia/reperfusion (I/R)‐induced nuclear factor κB (NF‐κB) over‐activation, probably via erythropoietin (EPO) and tumor necrosis factor α (TNF‐α), being essential for IP neuron‐induced astroprotection under the conditions of I/R. We concluded that NF‐κB‐mediated antioxidative stress is one of the mechanisms by which IP neurons protect astrocytes against I/R injury.
Broilers are frequently exposed to various immunological stresses, which lead to intestinal damage, weakened immunity, and even growth retardation. Lutein, as a kind of carotenoid, possesses ...antioxidant and immunomodulatory functions. Therefore, this study was conducted to investigate the effects of lutein on jejunal mucosal barrier function and inflammatory responses of yellow-feather broilers challenged with lipopolysaccharide (LPS). A total of two hundred eight-eight 1-day-old yellow-feather broilers were randomly allocated to 3 groups with 8 replicate cages containing 12 birds each. Birds were fed broken-rice-soybean basal diet containing 0, 20 and 40 mg/kg lutein (CON, LU20 and LU40) for 26 d. On days 21, 23, and 25 of the trial, broilers were intraperitoneally injected with LPS (1 mg/kg body weight). The results showed that, compared with CON group, LU40 supplementations significantly increased the average daily gain (ADG) of broilers at 1 to 21 and 22 to 26 d of age (P < 0.05), significantly decreased the ratio of feed to gain (F/G) of broilers at 22 to 26 d of age (P < 0.05). LU20 and LU40 supplementations increased goblet cell density in jejunum of broilers under LPS challenge, and LU20 supplementation elevated the villus area (P < 0.05). Scanning electron microscopy of jejunal mucosa revealed significant villi damage, while transmission electron microscopy demonstrated severe enterocyte damage and loss of cellular integrity in CON group. In particular, mitochondria were morphologically altered, appearing irregular or swollen. Apical junctional complexes between adjacent enterocytes were obviously shorter and saccular in CON group. LU20 and LU40 supplementations increased the mRNA expressions of Occludin, Claudin-1, and ZO-1 in the jejunal mucosa of broilers under LPS challenge (P < 0.05), restrained TLR4/MyD88/NF-κB pathway activation in the jejunal mucosa, decreased the mRNA expressions of IL-1β and IL-6, and strengthened the mRNA expressions of IL-4 and IL-10 (P < 0.05). Meanwhile, the protein expressions of p38 and JNK in LU40 group were lower than CON group (P < 0.05). It can be concluded that 40 mg/kg lutein supplementation improved LPS-induced jejunal mucosal barrier function and tamed inflammation of yellow-feather broilers.
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