Soluble Fibrinogen-Like Protein 2 Downregulation and Th17/Treg Imbalance in a Taurocholate-Induced Murine Experimental Model of Severe Acute Pancreatitis.

BACKGROUND: Severe acute pancreatitis (SAP) is associated with tremendous systemic inflammation, T-helper 17 (Th17) cells, and regulatory T (Treg) cells play an essential role in the inflammatory responses. Meanwhile, soluble fibrinogen-like protein 2 (Sfgl2) is a critical immunosuppressive effector cytokine of Treg cells and modulates immune responses. However, the impact of SAP induction on Sfgl2 expression and the role of Sfgl2 in immunomodulation under SAP conditions are largely unknown. METHODS: A taurocholate-induced mouse SAP model was established. The ratios of CD4+CD25+Foxp3+ Treg cells or CD4+IL-17+ Th17 cells in blood and pancreatic tissues as well as surface expression of CD80, CD86, and major histocompatibility complex class II (MHC-II) were determined by flow cytometry. Gene mRNA expression was determined by qPCR. Serum amylase and soluble factors were quantitated by commercial kits. Bone marrow-derived dendritic cells (DCs) were generated, and NF-κB/p65 translocation was measured by immunofluorescence staining. RESULTS: SAP induction in mice decreased the Th17/Treg ratio in the pancreatic tissue and increased the Th17/Treg ratio in the peripheral blood. In addition, SAP was associated with a reduced level of Sfgl2 in the pancreatic tissue and blood: higher levels of serum IL-17, IL-2, IFN-α, and TNF-α, and lower levels of serum IL-4 and IL-10. Furthermore, the SAP-induced reduction in Sfgl2 expression was accompanied by dysregulated maturation of bone marrow-derived DCs. CONCLUSIONS: SAP causes reduced Sfgl2 expression and Th17/Treg imbalance, thus providing critical insights for the development of Sfgl2- and Th17/Treg balance-targeted immunotherapies for patients with SAP.

Association Between the Blood Glucose Value at PACU Discharge and Postoperative Hypoglycemia in Nondiabetic Patients With Hyperglycemia After Hysteroscopic Surgery: A Retrospective Cohort Study.

PURPOSE: The target glycemic control for nondiabetic patients in the postanesthesia care unit (PACU) after hysteroscopic surgery remains unclear. Our goal is to determine the optimal level of glycemic control by finding the relationship between blood glucose level (BGL) leaving the PACU and postoperative hypoglycemia in nondiabetic patients. DESIGN: This retrospective cohort study was conducted at a comprehensive tertiary hospital in Chongqing, China between June 2018 and December 2020. METHODS: The target independent and dependent variables were BGL leaving the PACU and postoperative hypoglycemia, respectively. The primary outcome was the incidence of hypoglycemia. Logistic regression was used to explore the association between discharge BGL and hypoglycemia. The optimal glycemic control range was determined by using the receiver operating characteristic (ROC) curve. FINDINGS: Prior to insulin use, BGL in the insulin-using subgroup might be as high as 20 mmol/L. Hypoglycemia was related to the BGL while leaving the PACU (odds ratio (OR) 0.37 [95% confidence interval (CI) 0.22 to 0.65]). The best cut-off value (12.95 mmol/L) was determined by fitting the ROC curve. CONCLUSIONS: If severe hyperglycemia develops during hysteroscopic surgery in individuals with 5% glucose as the mediator of uterine distention, the recommendation is to maintain blood glucose above 12.95 mmol/L when treated with insulin.

Type†I Photoinitiator Based on Sustainable Carbon Dots.

Sustainable carbon dots comprising surficial oxime ester groups following homolytic bond cleavage exhibit potential as photoinitiators for traditional free radical photopolymerization. Carbon dots were made following a solvothermal procedure from sustainable furfural available from lignocellulose. Surficial aldehyde moieties reacted with hydroxylamine to the respective oxime while reaction with benzoyl chloride resulted in a biobased Type I photoinitiator comprising sustainable carbon dot (CD-PI). Photoinitiating ability was compared with the traditional photoinitiator (PI) ethyl (2,4,6-trimethyl benzoyl) phenyl phosphinate (TPO-L) by real-time FTIR with UV exposure at 365 nm. Photopolymer composition based on a mixture of urethane dimethacrylate (UDMA) and tripropylene glycol diacrylate (TPGDA) resulted in a similar final conversion of about 70 % using either CD-PI or TPO-L. Nevertheless, it appeared homogeneous in the case of compositions processed with CD-PI, while those made with TPO-L were heterogeneous as shown by two glass transition temperatures. Moreover, the migration rate of CD-PI in the cured samples was lower in comparison with those samples using TPO-L as PI.

An unusual cause of gastrointestinal bleeding: adult mixed-type Henoch-Schönlein purpura.

A 25-year-old man presented with 3-day history of abdominal pain, vomiting, diarrhea, and bloody stools. The contrast-enhanced CT examination of the abdomen detected thickening and edema of intestinal canal wall. The complete colonoscopy showed hyperemia, dropsy and erosion in the sigmoid colon and rectum. The biopsies revealed obvious bleeding points in mucosa. Then, wireless capsule endoscopy (OMOM ® JS-ME-I) was carried out and showed multiple lesions in the entire small intestine with diffused hyperemia, dropsy and erosion, even multiple and large ulcers. Subsequently, symmetrical scattered purpura distributed over the extensor surfaces of the lower limbs. Hence, a firm diagnosis of adult mixed-type Henoch-Schönlein purpura (HSP) was made. With the use of methylprednisolone, the patient was recovered. The patient remained well during our follow-up.

Rational Selection of Cyanines to Generate Conjugate Acid and Free Radicals for Photopolymerization upon Exposure at 860 nm.

Different cyanines absorbing in the NIR between 750 and 930 nm were applied to study the efficiency of both radical and cationic polymerization in combination with diaryliodonium salt. Variation of the connecting methine chain and structure of the terminal indolium moiety provided a deeper insight in the structure of the cyanine NIR-sensitizer and the efficiency to generate initiating radicals and conjugate acid. Photophysical studies were pursued by fluorescence spectroscopy providing a deeper understanding regarding the lifetime of the excited state and contribution of nonradiative deactivation resulting in generation of additional heat in the polymerization process. Furthermore, electrochemical experiments demonstrated connection to oxidation and reduction capability as influenced by the structural pattern of the sensitizer. LC-MS measurements provided a deeper pattern about the photoproducts formed. A nonamethine-based cyanine showed the best performance regarding bleaching in combination with an iodonium salt at 860 nm.

Circular RNA circHIAT1 inhibits proliferation and epithelial-mesenchymal transition of gastric cancer cell lines through downregulation of miR-21.

Gastric cancer (GC) is the third leading cause of cancer-related death worldwide. Circular RNA circHIAT1 has been proved to play an antitumor role. We aimed to explore the function and mechanism of circHIAT1 in GC. MKN28 and MKN45 cells were transfected with PLCDH-circHIAT1, miR-21 mimic, and relative control. Cell viability and apoptosis were examined through Cell Counting Kit-8 and flow cytometry, respectively. CircHIAT1 expression and other relative factors were tested through quantitative reverse transcription-polymerase chain reaction and Western blot analysis, respectively. Our findings demonstrated that circHIAT1 was lowly expressed in GC tissues. After transfection with PLCDH-circHIAT1 in MKN28 and MKN45 cells, cell viability was decreased, while the expression levels of p53 and p21 were raised, as well as apoptosis. Besides this, the epithelial-mesenchymal transition process was inhibited by PLCDH-circHIAT1 transfection. Mechanistically, miR-21 expression was upregulated in GC tissues and could be negatively regulated by circHIAT1. Further experiments showed that the addition of miR-21 mimic reversed the growth inhibition effects of circHIAT1 overexpression. Moreover, circHIAT1 inhibited the activation of phosphatase and tensin homolog/phosphatidylinositol 3 kinase/protein kinase B and extracellular signal-regulated kinase signal pathways via downregulating miR-21. CircHIAT1 functioned as a tumor inhibitor in GC cells through downregulating miR-21, and could be a novel target for GC treatment.

Hsa_circ_0001649 restrains gastric carcinoma growth and metastasis by downregulation of miR-20a.

BACKGROUND: Gastric carcinoma (GC) is a familiar carcinoma and serious threat to human health. We investigated the efficacy and mechanism of circular RNA hsa_circ_0001649 on the growth, migration, and invasion of GC cells. METHODS: microRNA (miR)-20a and hsa_circ_0001649 expression was investigated by RT-qPCR and was changed by cell transfection. CCK-8, flow cytometry, and BrdU assays were, respectively, used to investigate the efficacies of hsa_circ_0001649 and miR-20a on cell viability, apoptosis, and proliferation. Transwell assay was used to investigate the efficacies of hsa_circ_0001649 and miR-20a on cell migration and invasion. Moreover, the levels of cyclin D1, Bax, cleaved caspase-3, and signal pathway-related proteins were investigated by Western blot. RESULTS: Hsa_circ_0001649 was downregulated in GC cells and tissues. Upregulation of hsa_circ_0001649 restrained viability, proliferation, migration, and invasion, while promoted apoptosis. Furthermore, miR-20a was negatively regulated by hsa_circ_0001649 and miR-20a overexpression reversed the efficacy of hsa_circ_0001649 upregulation. Finally, upregulation of hsa_circ_0001649 restrained ERK and Wnt/ß-catenin pathways while miR-20a overexpression reversed these progresses. CONCLUSION: Upregulation of hsa_circ_0001649 restrained GC cell growth and metastasis by downregulating miR-20a and thereby inactivated ERK and Wnt/ß-catenin pathways.

Circular RNA circMAN2B2 promotes growth and migration of gastric cancer cells by down-regulation of miR-145.

BACKGROUND: CircMAN2B2 is a newly discovered circRNA that has been found to be an oncogene in lung cancer and glioma. The present study was designed to reveal the role of circMAN2B2 in gastric carcinoma (GC). METHODS: qRT-PCR method was utilized to examine circMAN2B2 expression in GC tissues and paracancerous tissues. Next, circMAN2B2 expression in SNU-16 and AGS cells was silenced by transfection. CCK-8 assay, colony formation assay, flow cytometer, Transwell assay, and Western blot were conducted for testing cell phenotype changes. Further, the downstream genes and signaling were uncovered by qRT-PCR and Western blot. RESULTS: As relative to paracancerous tissues, circMAN2B2 was high-expressed in GC tissues. Silence of circMAN2B2 clearly declined SNU-16 and AGS cells viability, survival, migration but enhanced apoptosis. Meanwhile, silence of circMAN2B2 induced the cleavage of caspases (-3 and -9), down-regulation of MMPs (-2 and -9), and up-regulation of miR-145. The impacts of circMAN2B2 silence toward SNU-16 and AGS cells were attenuated by miR-145 silence. Moreover, circMAN2B2 silence deactivated PI3K, AKT while activated JNK through regulating miR-145. CONCLUSION: This work presented the oncogenic function of circMAN2B2 in GC cells growth and migration. CircMAN2B2 exerted its function possibly through regulating miR-145 as well as PI3K/AKT and JNK pathways.

Silencing of long non-coding RNA PCAT6 restrains gastric cancer cell proliferation and epithelial-mesenchymal transition by targeting microRNA-15a.

Gastric cancer (GC) is a high mortality disease. We studied the function and mechanism of long non-coding RNA prostate cancer-associated transcript 6 (lncRNA PCAT6) on cell proliferation and epithelial-mesenchymal transition (EMT) in GC cells. CCK-8, flow cytometry and colony formation assay were respectively used to detect the cell viability, apoptosis and colony formation. PCAT6 and miR-15a expression were changed by cell transfection. Moreover, the level of Cyclin D1, p53, Bax, Cleaved caspase-3 and relate-proteins of EMT and cell pathways were investigated by Western blot. Besides, the level of miR-15a and PCAT6 was tested by RT-qPCR. Besides, the target relation between miR-15a and PCAT6 were tested by luciferase assay. PCAT6 was highly expressed in GC cells and tissues. Silencing of PCAT6 restrained the relate-proteins of cell proliferation and EMT. Furthermore, PCAT6 reversely regulated miR-15a and miR-15a inhibitor reversed the efficacy of sh-PCAT6 in cell proliferation and EMT. PCAT6 restrained the relate-proteins of RB/E2F and Wnt/ß-catenin pathways and miR-15a reverse this progress. Finally, PCAT6 was a target of miR-15a. Silencing of lncRNA PCAT6 restrained proliferation and EMT of GC cells by targeting miR-15a via RB/E2F and Wnt/ß-catenin pathways.

NIR-Sensitized Activated Photoreaction between Cyanines and Oxime Esters: Free-Radical Photopolymerization.

Cyanines comprising either a benzo[e]- or benzo[c,d]indolium core facilitate initiation of radical photopolymerization combined with high power NIR-LED prototypes emitting at 805 nm, 860 nm, or 870 nm, while different oxime esters function as radical coinitiators. Radical photopolymerization followed an initiation mechanism based on the participation of excited states, requiring additional thermal energy to overcome an existing intrinsic activation barrier. Heat released by nonradiative deactivation of the sensitizer favored the system, even under conditions where a thermally activated photoinduced electron transfer controls the reaction protocol. The heat generated internally by the NIR sensitizer promotes generation of the initiating reactive radicals. Sensitizers with a barbiturate group at the meso-position preferred to bleach directly, while sensitizers carrying a cyclopentene moiety unexpectedly initiated the photosensitized mechanism.

Decomposable Polyvinyl Alcohol-Based Super-Hydrophobic Three-Dimensional Porous Material for Effective Water/Oil Separation.

The development of the oil industry brings the critical problem of ocean pollution by oil spill or fossil fuels. The use of materials for water/oil separation is one of the effective approaches to solve this crisis. Polyvinyl alcohol (PVA) has been used  to prepare water/oil separation materials. Currently, glutaraldehyde has been employed as the cross-linking agent, which is well known to be toxic and environmentally unfriendly. Moreover, it is difficult to deal with the disposal of the Across-linked material. Here, we propose a strategy of fabricating macroporous material which was prepared by PVA and sodium silicate (Na2SiO3) in aqueous solution. Following through with the one-step method of sol-gel reaction of hydroxyl groups with trimethoxy(octadecyl)silane, the low surface energy substance was grafted on the macroporous material and a super-hydrophobic macroporous membrane for water/oil separation was prepared. As oil sorbent, the as-prepared dried super-hydrophobic PVA/Na2SiO3 porous materials (PSD6S) have the adsorption capacity of 1.8-7.0 g/g for oil uptake, which depends on the type of oil liquid. Typically, the separation efficiency of this material could reach more than 99% even after 10 times of use without the help of ambient pressure. It is noteworthy that the as-prepared samples could be easily decomposable and dissolvable completely in acidic medium at a rapid rate.

An Unusual Cause of Intestinal Ulcers Masquerading as Inflammatory Bowel Disease: A Case Report of Allied Disorders of Hirschsprung's Disease.

Background: Allied disorders of Hirschsprung's disease (ADHD) exhibit symptoms akin to those of Hirschsprung's disease, primarily characterized by intestinal obstruction, bowel dilatation, and chronic constipation. The occurrence of amyloid complications in patients with ADHD is infrequent. In this report, we present a case of ADHD with intestinal ulcers as the initial gastrointestinal manifestation, and subsequent pathological examination revealed the presence of amyloid deposits in the colonic mucosa. Case Report: A male patient, aged 20, exhibited recurring abdominal distension and intestinal obstruction for a duration of three years. Multiple colonoscopies revealed the presence of recurrent colonic ulcers, with pathological examination indicating the existence of amyloid deposits within the mucosal layer of the colon. Abdominal CT scans suggested colonic dilatation. Following a multidisciplinary consultation, a subtotal resection of the colon was performed, and subsequent postoperative pathology confirmed a decrease and absence of myenteric plexus ganglion cells. Considering the patient's symptoms and the findings from the postoperative pathology, a diagnosis of ADHD was made. The patient's symptoms resolved postoperatively and he was discharged from the hospital and followed up for 1 year in stable condition. Conclusion: Our study highlights the potential association between ADHD and the initial presentation of recurrent colonic ulcers, accompanied by amyloid deposition in the intestinal mucosa. This finding suggests a possible pathogenic mechanism for ADHD and offers a novel perspective on its diagnosis.

Correlation of chronic atrophic gastritis with gastric-specific circulating biomarkers.

BACKGROUND AND STUDY AIMS: It has been suggested that the combined detection of multiple serum biomarkers can effectively screen out the high-risk population of chronic atrophic gastritis in the general population. Therefore, it is necessary to establish an effective predictive model of chronic atrophic gastritis. PATIENTS AND METHODS: Serum biopsies were assessed using five stomach-specific circulating biomarkers pepsinogen I (PGI), PGII, PGI/II ratio, anti- H. pylori antibody, and gastrin-17 (G-17) to identify high-risk individuals and evaluate the risk of developing chronic atrophic gastritis. RESULTS: In the cross-sectional analysis, PGII, the PG ratio, G17, anti- H. pylori IgG were positively associated with the presence of chronic atrophic gastritis, and combined prediction of the five biomarkers was more accurate than single-factor prediction ((0.692 vs 0.54(PG1), 0.604 (PGⅡ), 0.616(PGI/II ratio), 0.629(G-17)). CONCLUSION: The combination of PGI, PGII, the PGI/II ratio, G17, and anti-H. pylori antibodies for serological analysis are helpful to screen chronic atrophic gastritis high-risk subjects from the general population and recommend that these people carry out further endoscopy and biopsy.

Association of diet and outdoor time with inflammatory bowel disease: a multicenter case-control study using propensity matching analysis in China.

Objective: To investigate the association between dietary and some other environmental factors and the risk of inflammatory bowel diseases (IBD) in Chinese population. Materials and methods: A multicenter case-control study was conducted involving 11 hospitals across China. A total of 1,230 subjects were enrolled consecutively, and diet and environmental factor questionnaires were collected. IBD patients were matched with healthy controls (HC) using propensity-score matching (PSM) at a 1:1 ratio with a caliper value of 0.02. Multivariate conditional logistic regression analyses were performed to evaluate the associations between diet, environmental factors, and IBD. Results: Moderate alcohol and milk consumption, as well as daily intake of fresh fruit, were protective factors for both Crohn's disease (CD) and ulcerative colitis (UC). Conversely, the consumption of eggs and chocolate increased the risk of IBD. Outdoor time for more than 25% of the day was a protective factor only for CD. In eastern regions of China, CD patients had higher egg consumption and less outdoor time, while UC patients consumed more chocolate. IBD patients from urban areas or with higher per capita monthly income consumed more fruit, eggs, and chocolate. Conclusions: This study reveals an association between specific foods, outdoor time, and the emergence of IBD in the Chinese population. The findings emphasize the importance of a balanced diet, sufficient outdoor time and activities, and tailored prevention strategies considering regional variations.

Antibiotic resistance of Helicobacter pylori isolated in the Southeast Coastal Region of China.

BACKGROUND: The resistance of Helicobacter pylori (H. pylori) to antibiotics is increasing worldwide, lowering its efficacy in current eradication therapies. This study evaluated H. pylori resistance to antibiotics in the southeast coastal region of China and suggests appropriate alternatives. MATERIALS AND METHODS: Seventeen thousand seven hundred and thirty one H. pylori strains were collected from eight areas of two provinces in coastal southeast China from 2010 to 2012. The resistance of these strains to six antibiotics was tested using the agar dilution method. RESULTS: The resistance rates to clarithromycin, metronidazole, levofloxacin, amoxicillin, gentamicin and furazolidone were 21.5, 95.4, 20.6, 0.1, 0.1 and 0.1%, respectively. Double, triple and quadruple antibacterial resistant percentages were 25.5, 7.5 and 0.1%, respectively. A positive association between the resistance to levofloxacin and to clarithromycin was found, but there was a negative correlation in the resistances to levofloxacin and to metronidazole. CONCLUSIONS: The prevalence of H. pylori resistance to clarithromycin, metronidazole, levofloxacin and multiple antibiotics in coastal southeast China is high. Choice of therapy should be individualized based on a susceptibility test in this region of the country.

Cytokine tumor necrosis factor alpha induces intestinal epithelial barrier dysfunction.

BACKGROUND AND AIMS: Epithelial barrier dysfunction is involved in a number of diseases in the body. The mechanism is to be further understood. The present study aimed to investigate the role of one of the common microbial products, flagellin (FGN), in the induction of intestinal epithelial barrier dysfunction. METHODS: We collected the colon epithelium specimens from 40 patients with ulcerative colitis (UC), 40 patients with Crohn's disease (CD) and 40 healthy volunteers. The expression of toll like receptors (TLR)5 of the specimens was assessed by RT-PCR and western blotting. The expression of tumor necrosis factor alpha (TNFα) and its role in compromising the barrier function in the intestinal epithelial cells, T84 cells, were observed by a cell culture model. RESULTS: The results showed that the expression of TLR5 was observed in the colon epithelium of healthy subjects that was increased in UC patients and further increased in CD patients. Treating T84 cells with FGN increased the expression of TNFα in the cells that caused the T84 cell apoptosis as well as compromised the T84 monolayer barrier function, which could be prevented by knocking down the gene of TNFα in T84 cells. CONCLUSIONS: We conclude that the human colon epithelial cells express detectable TLR5 that is increased in patients with CD and UC. The exposure to FGN can increase the expression of TNFα that further compromises the intestinal epithelial barrier function.

A fatal outcome in a patient with coeliac disease who suspended a strict gluten-free diet: a case report.

Coeliac disease (CD) is an autoimmune small bowel disease that occurs in susceptible individuals that develop an immunological reaction to gluten. A strict gluten-free diet (GFD) is the primary treatment for CD. This case report describes a patient with CD recurrence due to a discontinuation of a strict GFD by the patient. After recurrence, the patient developed fever and pancytopaenia, and quickly died of haemophagocytic lymphohistiocytosis (HLH). To the best of our knowledge, this is the first description of a case of CD associated with HLH due to discontinued GFD, which may contribute to improving the awareness of the importance of maintaining a strict GFD and having regular follow-up examinations.

Mesenteric phlebosclerosis with amyloidosis in association with the long-term use of medicinal liquor: A case report.

BACKGROUND: Mesenteric phlebosclerosis (MP) is a rare disease of the colon. The clinical manifestations of this disease are nonspecific and it may easily be misdiagnosed. We report a case of MP with amyloidosis in the colonic vessel walls in a patient with hypertension who had been consuming Chinese medicinal liquor for 10 years. We also review the relevant literature and summarize the characteristics of MP in patients in mainland China. CASE SUMMARY: A 64-year-old man was referred to our department from his primary hospital because of abdominal pain, diarrhea, and fever for almost 10 d. Computed tomography showed colon wall thickening, with threadlike calcifications in the mesenteric vein in the transverse colon. Colonoscopy revealed purple-blue mucosa with multiple ulcers in the ascending and transverse colon. Biopsy showed thickening and calcification of the vein walls, perivascular and mucosal collagen degeneration, and amyloidosis. The patient had been consuming Chinese medicinal liquor, mainly that made from gardenia fruit, for 10 years. Based on these results, a diagnosis of MP with amyloidosis was made. After conservative treatment, the patient's discomfort subsided and he was followed closely. The use of Chinese herbal medicine was suspected to play a role in the pathogenesis of MP. CONCLUSION: The clinical manifestations of MP are nonspecific. Recognition of its typical imaging findings, including multiple calcifications on computed tomography and purple-blue mucosal discoloration on colonoscopy, is vital.

Exogenous nicotinamide adenine dinucleotide administration alleviates ischemia/reperfusion-induced oxidative injury in isolated rat hearts via Sirt5-SDH-succinate pathway.

The metabolic disorder of succinate in myocardial tissue during ischemia-reperfusion can lead to the myocardial oxidative injury. The activation of succinate dehydrogenase (SDH) plays a vital role in the process. Silent information regulator 5 (Sirt5), a nicotinamide adenine dinucleotide (NAD)-dependent desuccinylase, desuccinylates and inactivates SDH thus exerting a protective effect on the myocardium. This research was designed to investigate whether exogenous NAD protects the myocardium from the ischemia-reperfusion-induced oxidative injury through regulating Sirt5-SDH pathway and succinate metabolism. We first found that myocardial total NAD level was remarkably increased with NAD treatment (10 mg/kg) for 14 days. NAD administration significantly decreased the lactate dehydrogenase (LDH) level in coronary leakage, decreased the malondialdehyde (MDA) level and increased the reduced glutathione/oxidized glutathione disulfide ratio (GSH/GSSG) in myocardial tissue. In addition, NAD treatment effectively attenuated the depression of cardiac function in the isolated rat hearts after ischemia-reperfusion. Furthermore, we found that exogenous NAD attenuated the succinate accumulation during ischemia and decreased its depleting rate during reperfusion. We also found that NAD administration had no obvious effects on myocardial Sirt5 and SDH-a expressions. However, the results of immunofluorescence showed that Sirt5 and SDH-a interacted in ischemia-reperfused myocardium. Utilizing co-immunoprecipitation method, we found that NAD administration promoted the Sirt5 and SDH-a interaction and decreased the succinylation level of SDH-a. These results implied that exogenous NAD administration promoted Sirt5-mediated SDH-a desuccinylation and decreased the activity of SDH-a, which attenuated the succinate accumulation during ischemia and its depleting rate during reperfusion and finally alleviated reactive oxygen species generation.