Cisd2 deficiency impairs neutrophil function by regulating calcium homeostasis via Calnexin and SERCA.

In the context of aging, the susceptibility to infectious diseases increases, leading to heightened morbidity and mortality. This phenomenon, termed immunosenescence, is characterized by dysregulation in the aging immune system, including abnormal alterations in lymphocyte composition, elevated basal inflammation, and the accumulation of senescent T cells. Such changes contribute to increased autoimmune diseases, enhanced infection severity, and reduced responsiveness to vaccines. Utilizing aging animal models becomes imperative for a comprehensive understanding of immunosenescence, given the complexity of aging as a physiological process in living organisms. Our investigation focuses on Cisd2, a causative gene for Wolfram syndrome, to elucidate on immunosenescence. Cisd2 knockout (KO) mice, serving as a model for premature aging, exhibit a shortened lifespan with early onset of aging-related features, such as decreased bone density, hair loss, depigmentation, and optic nerve degeneration. Intriguingly, we found that the Cisd2 KO mice present a higher number of neutrophils in the blood; however, isolated neutrophils from these mice display functional defects. Through mass spectrometry analysis, we identified an interaction between Cisd2 and Calnexin, a protein known for its role in protein quality control. Beyond this function, Calnexin also regulates calcium homeostasis through interaction with sarcoendoplasmic reticulum calcium transport ATPase (SERCA). Our study proposes that Cisd2 modulates calcium homeostasis via its interaction with Calnexin and SERCA, consequently influencing neutrophil functions. [BMB Reports 2024; 57(5): 256-261].

TXNIP-mediated crosstalk between oxidative stress and glucose metabolism.

Thioredoxin-interacting protein (TXNIP) has emerged as a key player in cancer and diabetes since it targets thioredoxin (TRX)-mediated redox regulation and glucose transporter (GLUT)-mediated metabolism. TXNIP consists of two arrestin (ARR, N-ARR and C-ARR) domains at its amino-terminus and two PPxY (PY) motifs and a di-leucine (LL) motif for endocytosis at its carboxyl-terminus. Here, we report that TXNIP shuffles between TRX and GLUTs to regulate homeostasis of intracellular oxidative stress and glucose metabolism. While TXNIP functions as a gatekeeper of TRX by default, it robustly interacted with class I GLUTs through its C-ARR domain upon increase of intracellular reactive oxygen species. This interaction prompted the surface expression downregulation and lysosomal degradation of GLUTs by its carboxyl-terminal LL endocytic signaling motif to attenuate glucose uptake. Consequently, TXNIP expression significantly limited glucose uptake, leading to the suppression of glycolysis, hexosamine biosynthesis, and the pentose phosphate pathway. Our findings establish a fundamental link between ROS and glucose metabolism through TXNIP and provide a promising target for the drug development against GLUT-related metabolic disorders.

When should patients take simethicone orally before colonoscopy for avoiding bubbles: A single-blind, randomized controlled study.

BACKGROUND: Many studies have reported the use of simethicone before colonoscopy removes bubbles. However, guidelines weakly recommend simethicone administration before colonoscopy. The present study aimed to confirm the advantages of taking simethicone and determine the appropriate time for taking simethicone. METHODS: We randomly assigned patients to the following 5 groups according to the administration time: 4 groups were divided based on 2 parameters (the day before and on the day of colonoscopy and before and after bowel cleansing) and the remaining group was the control group. We compared bubble score (BS), number of simethicone solution irrigations when visually obscured, satisfaction score of the endoscopist, insertion time. RESULTS: A total of 204 patients were included in the study. There was a difference in BS according to the timing of simethicone administration (P < .001). The group taking simethicone on the day of the test had a better BS than the group taking simethicone the day before (P < .001). The group taking simethicone on the previous day had a better BS than the control group (P = .001). In the group of taking simethicone on the examination day, the number of irrigations was lower, and satisfaction with the inspector was higher than group of taking simethicone on previous day and control group (both P < .001). The insertion time showed a non-significantly decreasing trend (P = .417). CONCLUSION: Administering simethicone reduced bubbles and facilitated effective colonoscopy, especially when administrating it on the day of examination. It needs to be administered on the day of the examination regardless of bowel preparation.

Lung-specific MCEMP1 functions as an adaptor for KIT to promote SCF-mediated mast cell proliferation.

Lung mast cells are important in host defense, and excessive proliferation or activation of these cells can cause chronic inflammatory disorders like asthma. Two parallel pathways induced by KIT-stem cell factor (SCF) and FcεRI-immunoglobulin E interactions are critical for the proliferation and activation of mast cells, respectively. Here, we report that mast cell-expressed membrane protein1 (MCEMP1), a lung-specific surface protein, functions as an adaptor for KIT, which promotes SCF-mediated mast cell proliferation. MCEMP1 elicits intracellular signaling through its cytoplasmic immunoreceptor tyrosine-based activation motif and forms a complex with KIT to enhance its autophosphorylation and activation. Consequently, MCEMP1 deficiency impairs SCF-induced peritoneal mast cell proliferation in vitro and lung mast cell expansion in vivo. Mcemp1-deficient mice exhibit reduced airway inflammation and lung impairment in chronic asthma mouse models. This study shows lung-specific MCEMP1 as an adaptor for KIT to facilitate SCF-mediated mast cell proliferation.

Benefits of Probiotic Pretreatment on the Gut Microbiota and Minor Complications after Bowel Preparation for Colonoscopy: A Randomized Double-Blind, Placebo-Controlled Pilot Trial.

The aim of this study was to evaluate the effects of probiotic pretreatment on the alteration and recovery of gut microbiota after bowel preparation and its correlation with minor complications. This was a randomized, double-blind, placebo-controlled pilot trial that included participants 40-65 years of age. Participants were randomly provided probiotics (active group) or placebo (placebo group) for 1 month before the colonoscopy and their feces collected. A total of 51 participants were included in the present study (26 in the active group and 25 in the placebo group). In the active group, the microbial diversity, evenness, and distribution were not significantly changed between before and after bowel preparation, but did change in the placebo group. The number of gut microbiota that decreased after bowel preparation in the active group was lower than in the placebo group. On the seventh day after colonoscopy, the gut microbiota in the active group was restored to almost the same level as before bowel preparation. In addition, we identified that several strains were assumed as key microbiota in early colonization and some taxa were increased only in the active group after bowel preparation. In multivariate analysis, taking probiotics before bowel preparation was identified as a significant factor for decreasing the duration of minor complications (odds ratio 0.13, 95% confidence interval 0.02-0.60, p = 0.027). Probiotic pretreatment had benefits on the alteration and recovery of gut microbiota and possible complications after bowel preparation. Probiotics may also aid in the early colonization of key microbiota.

OASL phase condensation induces amyloid-like fibrillation of RIPK3 to promote virus-induced necroptosis.

RIPK3-ZBP1-MLKL-mediated necroptosis is a proinflammatory cell death process that is crucial for antiviral host defence. RIPK3 self-oligomerization and autophosphorylation are prerequisites for executing necroptosis, yet the underlying mechanism of virus-induced RIPK3 activation remains elusive. Interferon-inducible 2'-5' oligoadenylate synthetase-like (OASL) protein is devoid of enzymatic function but displays potent antiviral activity. Here we describe a role of OASL as a virus-induced necroptosis promoter that scaffolds the RIPK3-ZBP1 non-canonical necrosome via liquid-like phase condensation. This liquid-like platform of OASL recruits RIPK3 and ZBP1 via protein-protein interactions to provide spatial segregation for RIPK3 nucleation. This process facilitates the amyloid-like fibril formation and activation of RIPK3 and thereby MLKL phosphorylation for necroptosis. Mice deficient in Oasl1 exhibit severely impaired necroptosis and attenuated inflammation after viral infection, resulting in uncontrolled viral dissemination and lethality. Our study demonstrates an interferon-induced innate response whereby OASL scaffolds RIPK3-ZBP1 assembly via its phase-separated liquid droplets to facilitate necroptosis-mediated antiviral immunity.

Herpesvirus-induced spermidine synthesis and eIF5A hypusination for viral episomal maintenance.

Spermidine is essential for cellular growth and acts as a prerequisite of hypusination, a post-translational modification of eukaryotic initiation factor 5A (eIF5A), allowing the translation of polyproline-containing proteins. Here, we show that oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV) increases spermidine synthesis and eIF5A hypusination to enhance expression of polyproline-containing latency-associated nuclear antigen (LANA) for viral episomal maintenance. KSHV upregulates intracellular spermidine levels by dysregulating polyamine metabolic pathways in three-dimensional (3D) culture and 2D de novo infection conditions. Increased intracellular spermidine leads to increased eIF5A hypusination, ultimately enhancing LANA expression. In contrast, inhibition of spermidine synthesis or eIF5A hypusination alleviates LANA expression, decreasing viral episomal maintenance and KSHV-infected cell proliferation in vitro and in vivo, which is reversed by spermidine supplement. This demonstrates that KSHV hijacks spermidine synthesis and eIF5A hypusination pathways to enhance LANA expression for viral episomal maintenance, suggesting polyamine metabolism and eIF5A hypusination as therapeutic targets for KSHV-induced tumorigenesis.

Colonoscopy Insertion in Patients with Gastrectomy: Does Position Impact Cecal Intubation Time?

BACKGROUND: A history of abdominal surgery is associated with difficulty in colonoscopy insertion. Few studies have reported effective colonoscopy insertion for patients who underwent abdominal surgery due to stomach cancer. AIM: We aimed to compare the impact of supine position (SP) and left lateral position (LLP) as the starting position of colonoscopy insertion in patients who underwent abdominal surgery due to stomach cancer. METHODS: This was a prospective, randomized controlled trial. Patients undergoing colonoscopy for screening or post-polypectomy surveillance after gastrectomy due to stomach cancer were enrolled and randomized to the SP or LLP group as the starting position of colonoscopy insertion. All colonoscopic examinations were performed with a transparent cap. The primary outcome was to compare the cecal intubation time between the two groups. RESULTS: A total of 224 patients were enrolled. The mean cecal intubation time was not significantly different between the SP and LLP groups (364.5 s versus 306.9 s; p = 0.105). In patients with a lower body mass index (< 21 kg/m2) or who underwent gastrectomy within three years, the mean cecal intubation time of the LLP group was shorter than the SP group. In the multivariate analysis for the factors affecting to increase in the cecal intubation time (> 5 min), the starting position was not an independent factor. CONCLUSION: Either the SP or LLP could serve as a possible starting position of colonoscopy insertion for patients who underwent abdominal surgery due to stomach cancer.

Age-dependent pathogenic characteristics of SARS-CoV-2 infection in ferrets.

While the seroprevalence of SARS-CoV-2 in healthy people does not differ significantly among age groups, those aged 65 years or older exhibit strikingly higher COVID-19 mortality compared to younger individuals. To further understand differing COVID-19 manifestations in patients of different ages, three age groups of ferrets are infected with SARS-CoV-2. Although SARS-CoV-2 is isolated from all ferrets regardless of age, aged ferrets (≥3 years old) show higher viral loads, longer nasal virus shedding, and more severe lung inflammatory cell infiltration, and clinical symptoms compared to juvenile (≤6 months) and young adult (1-2 years) groups. Furthermore, direct contact ferrets co-housed with the virus-infected aged group shed more virus than direct-contact ferrets co-housed with virus-infected juvenile or young adult ferrets. Transcriptome analysis of aged ferret lungs reveals strong enrichment of gene sets related to type I interferon, activated T cells, and M1 macrophage responses, mimicking the gene expression profile of severe COVID-19 patients. Thus, SARS-CoV-2-infected aged ferrets highly recapitulate COVID-19 patients with severe symptoms and are useful for understanding age-associated infection, transmission, and pathogenesis of SARS-CoV-2.

Cut Flower Characteristics and Growth Traits under Salt Stress in Lily Cultivars.

Salt stress is a major constraint of crop productivity because it reduces yield and limits the expansion of agriculture. This study investigated salt tolerance in 26 cultivars of cut lilies (Lilium hybrids) by examining the effect of salt stress on the growth and morphological characteristics of flowers and leaves and their physiological properties (chlorophyll a fluorescence). Salt stress significantly affected the growth and development of cut lilies. Canonical discriminant analysis indicates that the middle leaf width, number of flowers, first flower diameter, petal width, and chlorophyll a fluorescence were correlated with salt stress, whereas plant height, the middle leaf length, days to flowering, and sepal width were less affected by the stress. The cultivars examined were divided into three groups: Group 1 included the salt-sensitive cultivars, which failed to develop normal flowers; Group 2 included cultivars sensitive to salt stress but tolerant to osmotic stress; and Group 3 was the salt-tolerant group, which developed commercially valuable flowers. In conclusion, the cultivars contained a variable range of cut flower characteristics and growth traits that can be employed for lily breeding programs and as material for molecular mechanisms and signaling networks under salt stress.

Critical role of neutralizing antibody for SARS-CoV-2 reinfection and transmission.

Cases of laboratory-confirmed SARS-CoV-2 reinfection have been reported in a number of countries. Further, the level of natural immunity induced by SARS-CoV-2 infection is not fully clear, nor is it clear if a primary infection is protective against reinfection. To investigate the potential association between serum antibody titres and reinfection of SARS-CoV-2, ferrets with different levels of NAb titres after primary SARS-CoV-2 infection were subjected to reinfection with a heterologous SARS-CoV-2 strain. All heterologous SARS-CoV-2 reinfected ferrets showed active virus replication in the upper respiratory and gastro-intestinal tracts. However, the high NAb titre group showed attenuated viral replication and rapid viral clearance. In addition, direct-contact transmission was observed only from reinfected ferrets with low NAb titres (<20), and not from other groups. Further, lung histopathology demonstrated the presence of limited inflammatory regions in the high NAb titre groups compared with control and low NAb groups. This study demonstrates a close correlation between a low NAb titre and SARS-CoV-2 reinfection in a recovered ferret reinfection model.

Outcomes of reused transplanted kidneys using cases from the Korean Network for Organ Sharing database.

Due to organ shortages, the reuse of transplanted organs may be a good option for potential organ recipients. However, reports on the reuse of transplanted organs are rare. We retrospectively investigated cases of kidney donation since 2000 using the Korean Network for Organ Sharing database. Three cases of retransplanted kidneys were identified between 2000 and 2019. Of these three cases of kidney reuse, two involved reuse after a living-donor kidney transplant, and one case involved reuse after a deceased-donor kidney transplant. Another patient required a graftectomy due to bacterial infection immediately after transplantation. In two cases, the transplants were successful, and the kidneys have been functioning well for over 7 years. We believe that this case report highlights the opportunities for organ reuse among potential organ recipients and alleviates concerns about reused transplanted kidneys.

Effect of gut microbiome on minor complications after a colonoscopy.

BACKGROUND/AIMS: Minor complications that might occur after colonoscopy, including abdominal discomfort, bloating, diarrhea, and constipation, could a barrier for patients to undergo a screening colonoscopy. In this study, we aimed to identify the effect of gut microbial diversity and composition on minor complications after colonoscopy. METHODS: A total of 24 healthy subjects provided their stools before bowel preparation and on the 7th and 28th day after colonoscopy. On the 7th day after colonoscopy, the presence of minor complications was investigated using a questionnaire. We divided patients into 2 groups, the no complication group and complications group. The fecal microbial diversity, distribution, and composition were then compared between the groups. RESULTS: Five of the 24 subjects reported that they had undergone minor complications after colonoscopy. Most of the symptoms were mild and self-limited, but 1 patient needed medication. Interestingly, the Firmicutes/Bacteroidetes ratio of the initial stool samples before bowel preparation in the complication group was significantly higher than that in no complication group. After bowel preparation, the Firmicutes/Bacteroidetes ratio of the complication group decreased, but not in the no complication group. The microbial diversity of the no complication group decreased after bowel preparation, but not in the complication group. CONCLUSIONS: The gut microbial composition and diversity before and after bowel preparation could be considered as one of the causes of minor complications after colonoscopy. Further studies are needed to delineate the role of gut microbiota in the occurrence of minor complications after colonoscopy.

Analysis of Relative Scent Intensity, Volatile Compounds and Gene Expression in Freesia "Shiny Gold".

Scent is one of the most important economic traits in Freesia hybrida. "Shiny Gold", a popular cultivar in South Korea, is widely cultivated for its scent. The relative scent intensity of "Shiny Gold" was approximately 16% higher in full-bloomed flower when compared to the yellow bud stage, while tissue-specifically, tepals showed higher intensity in electronic-nose (e-nose) analysis. E-nose analysis also showed that the scent intensity of "Shiny Gold" was higher and lower than "10C3-424" and "10C3-894", respectively, and was similar to "Yvonne". These results correlated to those of the olfactory tests. In total, 19 volatile compounds, including linalool, ß-ocimene, D-limonene, trans-ß-ionone were detected in gas chromatography-mass spectrometry analysis. Among these, linalool was the major volatile compound, accounting for 38.7% in "Shiny Gold". Linalool synthase and TPS gene expression corresponded to the scent intensity of the four cultivars, with the lowest expression in the "10C3-424". TPS 2, TPS 3, TPS 5, TPS 6 and TPS 8 were highly expressed in both bud and flower in "Shiny Gold", while the expression of TPS 4 was lower, relative to other TPS genes in both the flowering stages. These results may aid in enhancing scent composition in Freesia cultivars using marker-assisted selection.

Negative regulation of NEMO signaling by the ubiquitin E3 ligase MARCH2.

NF-κB essential modulator (NEMO) is a key regulatory protein that functions during NF-κB- and interferon-mediated signaling in response to extracellular stimuli and pathogen infections. Tight regulation of NEMO is essential for host innate immune responses and for maintenance of homeostasis. Here, we report that the E3 ligase MARCH2 is a novel negative regulator of NEMO-mediated signaling upon bacterial or viral infection. MARCH2 interacted directly with NEMO during the late phase of infection and catalyzed K-48-linked ubiquitination of Lys326 on NEMO, which resulted in its degradation. Deletion of MARCH2 resulted in marked resistance to bacterial/viral infection, along with increased innate immune responses both in vitro and in vivo. In addition, MARCH2-/- mice were more susceptible to LPS challenge due to massive production of cytokines. Taken together, these findings provide new insight into the molecular regulation of NEMO and suggest an important role for MARCH2 in homeostatic control of innate immune responses.

Efficacy and Safety of Etomidate in Comparison with Propofol or Midazolam as Sedative for Upper Gastrointestinal Endoscopy.

BACKGROUND/AIMS: In this study, we compared the efficacy and safety of etomidate with those of propofol or midazolam for the maintenance of sedation during endoscopy. METHODS: The study enrolled patients who underwent sedative endoscopy in our hospital and divided them into three groups. Patients in each group were administered midazolam as induction therapy and were subsequently administered either midazolam (M + M group), propofol (M + P group), or etomidate (M + E group) as maintenance medication. The primary outcome was overall cardiovascular and respiratory adverse events. RESULTS: In total, 105 patients who underwent sedative endoscopic examination were enrolled. The outcomes related to the procedure and sedation were not significantly different among the groups. Overall cardiovascular and respiratory adverse events were observed in 9 patients (25.7%) in the M + M group, 8 patients (23.5%) in the M + P group, and 10 patients (27.8%) in the M + E group. The logistic regression analysis revealed that etomidate use was not an independent risk factor for overall cardiovascular and respiratory adverse events. CONCLUSION: The outcomes following the use of etomidate for maintenance after induction with midazolam for sedation in upper gastrointestinal endoscopy were not inferior to those following midazolam or propofol use from the perspectives of safety and efficacy.

Oncogenic human herpesvirus hijacks proline metabolism for tumorigenesis.

Three-dimensional (3D) cell culture is well documented to regain intrinsic metabolic properties and to better mimic the in vivo situation than two-dimensional (2D) cell culture. Particularly, proline metabolism is critical for tumorigenesis since pyrroline-5-carboxylate (P5C) reductase (PYCR/P5CR) is highly expressed in various tumors and its enzymatic activity is essential for in vitro 3D tumor cell growth and in vivo tumorigenesis. PYCR converts the P5C intermediate to proline as a biosynthesis pathway, whereas proline dehydrogenase (PRODH) breaks down proline to P5C as a degradation pathway. Intriguingly, expressions of proline biosynthesis PYCR gene and proline degradation PRODH gene are up-regulated directly by c-Myc oncoprotein and p53 tumor suppressor, respectively, suggesting that the proline-P5C metabolic axis is a key checkpoint for tumor cell growth. Here, we report a metabolic reprogramming of 3D tumor cell growth by oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV), an etiological agent of Kaposi's sarcoma and primary effusion lymphoma. Metabolomic analyses revealed that KSHV infection increased nonessential amino acid metabolites, specifically proline, in 3D culture, not in 2D culture. Strikingly, the KSHV K1 oncoprotein interacted with and activated PYCR enzyme, increasing intracellular proline concentration. Consequently, the K1-PYCR interaction promoted tumor cell growth in 3D spheroid culture and tumorigenesis in nude mice. In contrast, depletion of PYCR expression markedly abrogated K1-induced tumor cell growth in 3D culture, not in 2D culture. This study demonstrates that an increase of proline biosynthesis induced by K1-PYCR interaction is critical for KSHV-mediated transformation in in vitro 3D culture condition and in vivo tumorigenesis.

Risk of Delayed Bleeding after a Colorectal Endoscopic Mucosal Resection without Prophylactic Clipping: Single Center, Observational Study.

BACKGROUND/AIMS: Bleeding is one of the major complications of a colorectal polypectomy. The aim of this study was to identify the risk of delayed bleeding, particularly after a colorectal endoscopic mucosal resection (EMR) without prophylactic clipping. METHODS: Between April 2014 and August 2014, patients who underwent colorectal EMR (≥6 mm and <2 cm) without prophylactic clipping were included. This study evaluated the incidence of delayed bleeding and the associated factors after colorectal EMR without prophylactic clipping. RESULTS: A total of 717 colorectal polyps (≥6 mm and <2 cm) of 243 patients resected by colorectal EMR in the study period were evaluated. The mean age of the patients was 63 years; 165 patients were men and 78 patients were women. The mean polyp size removed by colorectal EMR was 9.0 mm (range 6.0-19.0), and the number of polyps larger than 1 cm was 212 (29.6%). Delayed bleeding after colorectal EMR occurred in 12 polyps (1.7%) in eight patients (3.3%), and there were no significant risk factors affecting delayed bleeding. CONCLUSIONS: This study identified that the incidence of delayed bleeding on colorectal polyps (≥6 mm and <2 cm) after EMR without prophylactic clipping was 3.3%, but no significant risk factors affecting delayed bleeding were found.

Publisher Correction: SERPINB1-mediated checkpoint of inflammatory caspase activation.

In the version of this article initially published, the label (CASP4-C285A-HA) above the second and fifth lanes in the right blot in Fig. 1e is incorrect; the correct label is CASP4-C258A-HA. Also, the two labels at right above the plot in Fig. 6c were switched; the far right label should be 'Co-housed Serpinb1a-/-' (in red font) and the label just to its left (above the fourth column) should be 'Co-housed WT' (in black font). Finally, the bottom two symbols in the key to Fig. 7d were switched; the red circle should identify 1CARD-SUMO (TEV) and the blue triangle should identify 1CARD-SUMO + SERPINB1 (TEV). The errors have been corrected in the HTML and PDF versions of the article.

SERPINB1-mediated checkpoint of inflammatory caspase activation.

Inflammatory caspases (caspase-1, caspase-4, caspase-5 and caspase-11 (caspase-1/-4/-5/-11)) mediate host defense against microbial infections, processing pro-inflammatory cytokines and triggering pyroptosis. However, precise checkpoints are required to prevent their unsolicited activation. Here we report that serpin family B member 1 (SERPINB1) limited the activity of those caspases by suppressing their caspase-recruitment domain (CARD) oligomerization and enzymatic activation. While the reactive center loop of SERPINB1 inhibits neutrophil serine proteases, its carboxy-terminal CARD-binding motif restrained the activation of pro-caspase-1/-4/-5/-11. Consequently, knockdown or deletion of SERPINB1 prompted spontaneous activation of caspase-1/-4/-5/-11, release of the cytokine IL-1ß and pyroptosis, inducing elevated inflammation after non-hygienic co-housing with pet-store mice and enhanced sensitivity to lipopolysaccharide- or Acinetobacter baumannii-induced endotoxemia. Our results reveal that SERPINB1 acts as a vital gatekeeper of inflammation by restraining neutrophil serine proteases and inflammatory caspases in a genetically and functionally separable manner.