Mouse Tissues Research Articles

Deletion of YTHDF1 (not YTHDF3) reduced brain and gut damage after traumatic brain injury

ABSTRACT Objective: To determine whether YTHDF1 and YTHDF3 play the same role in brain and gut damage after traumatic brain injury (TBI). Methods: We generated YTHDF1-/- and YTHDF3-/- mice using CRISPR/Cas9 technology, established a mouse brain injury model through severe controlled cortical impact (CCI), and finally observed the different types of damage between YTHDF1-/- and YTHDF3-/- mice by analysing the levels of oedema proteins in cortical tissue and inflammatory proteins and histopathological lesions in brain and gut tissues in mice at 3 days after CCI. Result: Compared with WT mice, YTHDF1-/- mice had decreased levels of oedema in cortical tissue and inflammation and histopathological lesions in brain and gut tissues at 3 days post-CCI, but YTHDF3-/- mice did not. Conclusion: Our results suggest that deletion of YTHDF1, but not YTHDF3, could reduce damage to the brain and gut following TBI.

Gingipain from Porphyromonas gingivalis causes insulin resistance by degrading insulin receptors through direct proteolytic effects

Periodontitis is a critical risk factor for the occurrence and development of diabetes. Porphyromonas gingivalis may participate in insulin resistance (IR) caused by periodontal inflammation, but the functional role and specific mechanisms of P. gingivalis in IR remain unclear. In the present study, clinical samples were analysed to determine the statistical correlation between P. gingivalis and IR occurrence. Through culturing of hepatocytes, myocytes, and adipocytes, and feeding mice P. gingivalis orally, the functional correlation between P. gingivalis and IR occurrence was further studied both in vitro and in vivo. Clinical data suggested that the amount of P. gingivalis isolated was correlated with the Homeostatic Model Assessment for IR score. In vitro studies suggested that coculture with P. gingivalis decreased glucose uptake and insulin receptor (INSR) protein expression in hepatocytes, myocytes, and adipocytes. Mice fed P. gingivalis tended to undergo IR. P. gingivalis was detectable in the liver, skeletal muscle, and adipose tissue of experimental mice. The distribution sites of gingipain coincided with the downregulation of INSR. Gingipain proteolysed the functional insulin-binding region of INSR. Coculture with P. gingivalis significantly decreased the INSR–insulin binding ability. Knocking out gingipain from P. gingivalis alleviated the negative effects of P. gingivalis on IR in vivo. Taken together, these findings indicate that distantly migrated P. gingivalis may directly proteolytically degrade INSR through gingipain, thereby leading to IR. The results provide a new strategy for preventing diabetes by targeting periodontal pathogens and provide new ideas for exploring novel mechanisms by which periodontal inflammation affects the systemic metabolic state.

TRAP1 drives smooth muscle cell senescence and promotes atherosclerosis via HDAC3-primed histone H4 lysine 12 lactylation.

Vascular smooth muscle cell (VSMC) senescence is crucial for the development of atherosclerosis, characterized by metabolic abnormalities. Tumour necrosis factor receptor-associated protein 1 (TRAP1), a metabolic regulator associated with ageing, might be implicated in atherosclerosis. As the role of TRAP1 in atherosclerosis remains elusive, this study aimed to examine the function of TRAP1 in VSMC senescence and atherosclerosis. TRAP1 expression was measured in the aortic tissues of patients and mice with atherosclerosis using western blot and RT-qPCR. Senescent VSMC models were established by oncogenic Ras, and cellular senescence was evaluated by measuring senescence-associated β-galactosidase expression and other senescence markers. Chromatin immunoprecipitation (ChIP) analysis was performed to explore the potential role of TRAP1 in atherosclerosis. VSMC-specific TRAP1 deficiency mitigated VSMC senescence and atherosclerosis via metabolic reprogramming. Mechanistically, TRAP1 significantly increased aerobic glycolysis, leading to elevated lactate production. Accumulated lactate promoted histone H4 lysine 12 lactylation (H4K12la) by down-regulating the unique histone lysine delactylase HDAC3. H4K12la was enriched in the senescence-associated secretory phenotype (SASP) promoter, activating SASP transcription and exacerbating VSMC senescence. In VSMC-specific Trap1 knockout ApoeKO mice (ApoeKOTrap1SMCKO), the plaque area, senescence markers, H4K12la, and SASP were reduced. Additionally, pharmacological inhibition and proteolysis-targeting chimera (PROTAC)-mediated TRAP1 degradation effectively attenuated atherosclerosis in vivo. This study reveals a novel mechanism by which mitonuclear communication orchestrates gene expression in VSMC senescence and atherosclerosis. TRAP1-mediated metabolic reprogramming increases lactate-dependent H4K12la via HDAC3, promoting SASP expression and offering a new therapeutic direction for VSMC senescence and atherosclerosis.

Yishen Jiangzhuo decoction attenuates cisplatin‑induced acute kidney injury by inhibiting inflammation, oxidative stress and apoptosis through the TNF signal pathway.

The present study aimed to investigate the therapeutic effects and mechanisms of Yishen Jiangzhuo decoction (YSJZD) in a mouse model of cisplatin-induced acute kidney injury (AKI). The mice were divided into the NC, cisplatin and cisplatin + YSJZD groups. A concentration-dependent effect of YSJZD on cisplatin-induced AKI was observed and the optimal concentration for intervention was calculated. Changes in blood urea nitrogen and serum creatinine levels combined with hematoxylin and eosin and periodic acid-Schiff staining and transmission electron microscopy observations indicated that YSJZD enhanced renal function, reduced pathological injury and protected renal tubular epithelial cells in cisplatin-induced AKI mice. The results of the transcriptomic and enrichment analyses showed that the mechanisms of YSJZD may be associated with inflammation, oxidation, apoptosis and the TNF signal pathway. Immunofluorescence, oxidative stress index, terminal deoxynucleotidyl transferase dUTP nick end labeling assay and western blotting revealed that YSJZD downregulated apoptosis in the renal tissues of AKI mice and further decreased the expression levels of p-p65, p-p38 MAPK, TNF-α, cleaved-caspase-3 and malondialdehyde, while increasing the levels of NAD-dependent protein deacetylase sirtuin-3, glutathione and superoxide dismutase. Overall, the results showed that YSJZD could effectively abrogate cisplatin-induced AKI in mice through mechanisms primarily related to its anti-inflammatory, antioxidative and antiapoptotic effects by inhibited the TNF signal pathway. YSJZD warrants further investigation as a clinical empirical prescription.

VALD-2 mitigates cisplatin-induced acute kidney injury: Mechanistic insights into oxidative stress modulation and inflammation suppression.

This study explores the compelling antitumor properties of VALD-2, a synthetic Schiff base ligand known for its low toxicity. The focus is on investigating VALD-2's protective role against cisplatin-induced acute kidney injury (AKI) in mice, with a specific emphasis on mitigating oxidative stress and inflammation. The study involves daily intraperitoneal injections of amifostine or VALD-2 over 7 days to establish an AKI model. Subsequently, mice were assigned to normal control, cisplatin group, cisplatin + amifostine group, and cisplatin + VALD-2 10 mg/kg group, cisplatin + VALD-2 20 mg/kg, and cisplatin + VALD-2 40 mg/kg. Kidney injury is assessed through serum blood urea nitrogen (BUN) and creatinine (Cr) activity assays. Levels of inflammatory factors,tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), in kidney tissue of mice were assessed through enzyme-linked immunosorbent assay (ELISA). The protective effect of VALD-2 is further examined through HE staining to observe pathological changes in kidney injury. The ultrastructural changes of renal cells and tubular epithelial cells were observed by electron microscopy under experimental conditions, indicating the effect of VALD-2 on reversing cisplatin-induced renal injury. The study delves into VALD-2's protective mechanisms against cisplatin-induced kidney injury by using western blot analysis to assess the expression levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) in kidney tissues. VALD-2 demonstrates significant improvement in cisplatin-induced AKI, as evidenced by increased BUN and Cr levels. It effectively protects kidney tissue from oxidative damage, enhancing SOD and GSH-Px activities while reducing MDA levels. The study also reveals a decrease in TNF-α and IL-6 levels, supported by ELISA results, and histological findings confirm anti-nephrotoxic effects. Western blot analysis shows an upregulation of antioxidant enzymes (SOD, GSH-Px) and a reduction in MDA production. VALD-2 emerges as a promising mitigator of cisplatin-induced AKI, showcasing its ability to enhance oxidative stress-related protein expression. The findings suggest VALD-2 as a potential therapeutic agent for protecting against cisplatin-induced kidney injury.

Prevention and treatment of peri-implant fibrosis by functionally inhibiting skeletal cells expressing the leptin receptor.

The cellular and molecular mediators of peri-implant fibrosis-a most common reason for implant failure and for surgical revision after the replacement of a prosthetic joint-remain unclear. Here we show that peri-implant fibrotic tissue in mice and humans is largely composed of a specific population of skeletal cells expressing the leptin receptor (LEPR) and that these cells are necessary and sufficient to generate and maintain peri-implant fibrotic tissue. In a mouse model of tibial implantation and osseointegration that mimics partial knee arthroplasty, genetic ablation of LEPR+ cells prevented peri-implant fibrosis and the implantation of LEPR+ cells from peri-implant fibrotic tissue was sufficient to induce fibrosis in secondary hosts. Conditional deletion of the adhesion G-protein-coupled receptor F5 (ADGRF5) in LEPR+ cells attenuated peri-implant fibrosis while augmenting peri-implant bone formation, and ADGRF5 inhibition by the intra-articular or systemic administration of neutralizing anti-ADGRF5 in the mice prevented and reversed peri-implant fibrosis. Pharmaceutical agents that inhibit the ADGRF5 pathway in LEPR+ cells may be used to prevent and treat peri-implant fibrosis.

Rapid Analysis of Colonic Metabolomics in High-Fat Diet Mice by Extraction Electrospray Ionization Mass Spectrometry (EESI-MS).

Propolis exhibits significant anti-inflammatory, antidiabetic, and antiobesity properties in both mouse models and clinical applications. However, the underlying metabolic mechanisms remain poorly understood. Traditional metabolomic methods that rely on chromatographic separation require complex preprocessing steps and extended detection periods. In this study, we employed extraction electrospray ionization mass spectrometry combined with multivariate analysis to directly profile metabolites in the colon tissue of mice. Our findings demonstrate the efficacy of ethanol extract of propolis (EEP) in mitigating weight gain, reducing inflammatory cytokines, and improving insulin resistance induced by a high-fat diet. Additionally, EEP enhanced glucose tolerance. Through collision-induced dissociation experiments, we identified 26 metabolites, with 4-hydroxyphenylacetic acid, protocatechuic acid, caffeic acid, ferulic acid, hippuric acid, histidine, and tryptophan emerging as potential biomarkers. Notably, tryptophan exhibited the highest content at 8.25 mg/g. Our research facilitates rapid profiling of colon metabolites, underscoring its significant potential for broader applications in animal metabolomic studies.

The circadian rhythm: A key variable in aging?

The determination of age-related transcriptional changes may contribute to the understanding of health and life expectancy. The broad application of results from age cohorts may have limitations. Altering sample sizes per time point or sex, using a single mouse strain or tissue, a limited number of replicates, or omitting the middle of life can bias the surveys. To achieve higher general validity and to identify less distinctive players, bulk RNA sequencing of a mouse cohort, including seven organs of two strains from both sexes of 5 ages, was performed. Machine learning by bootstrapped variable importance and selection methodology (Boruta) was used to identify common aging features where the circadian rhythms (CiR) transcripts appear as promising age markers in an unsupervised analysis. Pathways of 11 numerically analyzed local network clusters were affected and classified into four major gene expression profiles, whereby CiR and proteostasis candidates were particularly conspicuous with partially opposing changes. In a data-based interaction association network, the CiR-proteostasis axis occupies an exposed central position, highlighting its relevance. The computation of 11,830 individual transcript associations provides potential superordinate contributors, such as hormones, to age-related changes, as in CiR. In hormone-sensitive LNCaP cells, short-term supraphysiologic levels of the sex hormones dihydrotestosterone or estradiol increase the expression of the CiR transcript Bhlhe40 and the associated senescence regulator Cdkn2b (p15). According to these findings, the bilateral dysregulation of CiR appears as a fundamental protagonist of aging, whose transcripts could serve as a biological marker and its restoration as a therapeutic opportunity.

CircSorbs1 regulates myocardial regeneration and reduces cancer therapy-related cardiovascular toxicity through the Mir-99/GATA4 pathway

Due to the cancer therapy-related cardiovascular toxicity, heart failure following cancer therapy has a significant mortality rate. Gene-targeted therapy promotes the re-entry of existing cardiomyocytes into the cell cycle to achieve myocardial regeneration, which is a promising strategy for preventing and treating heart failure after myocardial infarction. Circular RNAs (circRNAs) are considered as potential targets for myocardial regeneration due to their strong stability, resistance to degradation, and potential role in heart development and cardiovascular diseases. By comparing the myocardial tissue of mice in the sham operation group and the Doxorubicin therapy group (DOX), we observed a significant decrease in Cirsorbs expression in the DOX group. Cirsorbs was predominantly localized in cardiomyocytes and exhibited high conservation. Subsequent investigations revealed that Cirsorbs could promote myocardial proliferation and inhibit myocardial apoptosis. Mechanistic studies further demonstrated that Cirsorbs could bind to miR99 and reduce its expression level. Meanwhile, miR99 was found to bind to GATA4 mRNA and decrease its expression level. The binding of Cirsorbs to miR99 alleviated the repression of miR99, thereby enhancing GATA4 expression and the transcription of downstream cyclin A2 and cyclin E1. This, in turn, increased cardiomyocyte proliferation and reduced apoptosis. In conclusion, Cirsorbs holds promise as an effective target for myocardial regeneration in reducing cancer therapy-related cardiovascular toxicity.

Absence of Aquaporin-4 (AQP4) Prolongs the Presence of a CD11c+ Microglial Population during Postnatal Corpus Callosum Development

Aquaporin-4 (AQP4) expression is associated with the development of congenital hydrocephalus due to its structural role in the ependymal membrane. Gene expression analysis of periaqueductal tissue in AQP4-knockout (KO) mice at 11 days of age (P11) showed a modification in ependymal cell adhesion and ciliary protein expression that could alter cerebrospinal fluid homeostasis. A microglial subpopulation of CD11c+ cells was overexpressed in the periaqueductal tissue of mice that did not develop hydrocephalus, suggesting a possible protective effect. Here, we verified the location of this CD11c+ expression in the corpus callosum (CC) and cerebellum of AQP4-KO mice and analysed its time course. Immunofluorescence labelling of the CD11c protein in the CC and cerebellum of WT and KO animals at P3, P5, P7 and P11 confirmed an expanded presence of these cells in both tissues of the KO animal; CD11c+ cells appeared at P3 and reached a peak at P11, whereas in the WT animal, they appeared at P5, reached their peak at P7 and were undetectable by P11. The gene expression analysis in the CC samples at P11 confirmed the presence of CD11c+ microglial cells in this tissue. Among the more than 4000 overexpressed genes, Spp1 stood out with the highest differential gene expression (≅600), with other genes, such as Gpnmb, Itgax, Cd68 and Atp6v0d2, also identified as overexpressed. Therefore, CD11c+ cells appear to be necessary for normal corpus callosum development during postnatal life, and the absence of AQP4 prolonged its expression in this tissue.

Circ_19038 and lnc-AK016022 synergistically regulate Sirt1 to promote remyelination and alleviate white matter injury in preterm mice

Maternal inflammation can lead to premature birth and fetal brain damage. CircRNA_19038 and lncRNA-AK016022 have been shown to be significantly reduced in brain tissues of preterm mice, while whether they are involved in the regulation of preterm white matter injury remains to be explored. Pregnant mice were intraperitoneally injected with lipopolysaccharide (LPS) to establish a preterm brain injury model. Healthy mice born at term served as controls. Lentivirus-mediated circ_19038 overexpression vector (LV-circ_19038), LV-lnc-AK016022, LV-Sirt1 and LV-sh-Sirt1 were administered to preterm mice through the ventricles. The expression levels of circ_19038, lnc-AK016022 and Sirt1 in the brain tissues of preterm mice were significantly lower than those of full-term healthy mice, and circ_19038 and lnc-AK016022 were co-localized in the brain tissues. Upregulation of circ_19038 or/and lnc-AK016022 promoted remyelination and alleviated white matter structural damage, neuroinflammation, and long-term cognitive and motor deficits in preterm mice, and the combined effect of circ_19038 and lnc-AK016022 showed better results. Primary mouse neuronal cells were isolated to investigate the regulatory effects of circ_19038 and lnc-AK016022 on Sirt1. Circ_19038 and lnc-AK016022 jointly promoted the expression of Sirt1 by adsorbing miR-1b and miR-328, respectively. Moreover, silencing Sirt1 antagonized the beneficial effects of circ_19038 or/and lnc-AK016022 on brain white matter injury in preterm mice. In conclusion, circ_19038 and lnc-AK016022 synergistically regulated Sirt1 expression to promote remyelination and alleviate white matter injury in preterm mice.

Irisin preserves mitochondrial integrity and function in tubular epithelial cells after ischemia-reperfusion-induced acute kidney injury.

A myokine secreted by skeletal muscles during exercise called irisin mitigates ischemia-reperfusion (I/R) injury in epithelial cells of various organs by limiting damage to mitochondria. We test whether irisin may preserve the mitochondrial integrity and function in renal tubular epithelial cells and protect against ischemia-reperfusion-induced acute kidney injury (AKI). We correlated serum irisin levels with serum creatinine and BUN levels from both AKI patients and healthy individuals. In mice with irisin administration, various renal injury markers such as serum creatinine, BUN, kidney injury molecule-1 (Kim-1), and neutrophil gelatinase-associated lipocalin (NGAL), and renal histopathology were assessed after I/R. To identify the potential mechanisms of the protective of irisin's protective effect, we perfused proximal tubules under confocal microscopy and analyzed kidney tissues by qPCR, western blot, and immunohistochemistry. Serum irisin correlated inversely with serum creatinine and BUN levels were significantly lower in AKI patients than in healthy subjects. Administering irisin to mice after I/R decreased biomarker levels for AKI including serum creatinine, BUN, Kim-1, NAGL and lessened histological changes. In kidney tissues of mice, irisin upregulated the mitochondrial autophagy marker protein microtubule-associated protein 1 light chain 3 (LC3), the mitochondrial autophagy pathway-related proteins PTEN-induced putative kinase 1 (PINK1) and Parkinson's disease 2 parkin (PARK2) and downregulated the reactive substrate protein sequestosome 1 (P62) and mitochondrial membrane proteins translocase of outer mitochondrial membrane 20 (TOM20) and translocase of inner mitochondrial membrane 23 (TIM23). Irisin protects against renal I/R injury, which may involve the preservation of mitochondrial integrity and function.

Diet of Andean leaf-eared mice (Phyllotis) living at extreme elevations on Atacama volcanoes: insights from metagenomics, DNA metabarcoding, and stable isotopes.

On the flanks of >6000 m Andean volcanoes that tower over the Atacama Desert, leaf-eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. What the mice eat in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is provided by windblown insects that accumulate in snowdrifts ('aolian deposits'). It is also possible that mice feed on saxicolous lichen or forms of cryptic vegetation that have yet to be discovered at such high elevations. We tested hypotheses about the diet of mice living at extreme elevations on Atacama volcanoes by combining metagenomic and DNA metabarcoding analyses of gut contents with stable-isotope analyses of mouse tissues. Genomic analyses of contents of the gastrointestinal tract of a live-captured mouse from the 6739 m summit of Volcán Llullaillaco revealed evidence for an opportunistic but purely herbivorous diet, including lichens. Although we found no evidence of animal DNA in gut contents of the summit mouse, stable isotope data indicate that mice native to elevations at or near vegetation limits (~5100 m) include a larger fraction of animal prey in their diet than mice from lower elevations. Some plant species detected in the gut contents of the summit mouse are known to exist at lower elevations at the base of the volcano and in the surrounding Altiplano, suggesting that such plants may occur at higher elevations beneath the snowpack or in other cryptic microhabitats.

Nobiletin alleviates macrophage M2 polarization by activating AMPK-mTOR-mediated autophagy in pulmonary fibrosis mice

Nobiletin (NOB), a polymethoxylated flavone isolated from citrus peels, is a promising dietary treatment for lung diseases, such as pulmonary fiborsis. In this work, the underlying mechanisms of NOB’s preventative effect on pulmonary fibrosis were explored using bleomycin-exposed mice and IL-4-induced M2 polarization of the macrophages. Results showed that NOB treatment could significantly ameliorate lung fibrosis by suppressing pathological damages, collagen deposition, and fibroblat activation. Moreover, NOB obviously reduced the M2 macrophage-related proteins, including CD206, Arg1, and pro-fibrotic mediators such as TGF-β and CTGF, which might contribute to the antifibrosis effect of NOB. Network analysis of the differentially expressed genes in NOB-treated M2 macrophages showed that autophagy, mTOR signaling pathway, and AMPK signaling pathway might be involved in the effects of NOB. Further exploration illustrated that autophagy was enhanced in NOB-treated lung and M2 macrophages.The addition of 3MA, an autophagy inhibitor, could significantly weaken the effect of NOB on lung fibrosis and macrophage M2 polarization. Additionally, NOB also markedly decreased the expression of p-AMPK, p-mTOR, and p-P70S6K in the M2 macrophages and lung tissues of BLM-exposed mice. Compound C, an AMPK agonist, significantly suppressed NOB-induced activation of AMPK and mTOR signals, as well as its inhibitory effect on autophagy, M2 macrophages and lung fibrosis both in vitro and in vivo, supporting the requirement of AMPK-mTOR-mediated autophagy for the NOB’s antifibrosis activity. Taken together, this study suggests that NOB ameliorates pulmonary fibrosis likely involving the inhibition of M2 macrophage via activating AMPK-mTOR-mediated autophagy.

Gene body DNA hydroxymethylation restricts the magnitude of transcriptional changes during aging

DNA hydroxymethylation (5hmC), the most abundant oxidative derivative of DNA methylation, is typically enriched at enhancers and gene bodies of transcriptionally active and tissue-specific genes. Although aberrant genomic 5hmC has been implicated in age-related diseases, its functional role in aging remains unknown. Here, using mouse liver and cerebellum as model organs, we show that 5hmC accumulates in gene bodies associated with tissue-specific function and restricts the magnitude of gene expression changes with age. Mechanistically, 5hmC decreases the binding of splicing associated factors and correlates with age-related alternative splicing events. We found that various age-related contexts, such as prolonged quiescence and senescence, drive the accumulation of 5hmC with age. We provide evidence that this age-related transcriptionally restrictive function is conserved in mouse and human tissues. Our findings reveal that 5hmC regulates tissue-specific function and may play a role in longevity.

Puerarin Attenuates Insulin Resistance by Inhibiting Endoplasmic Reticulum Stress and Suppresses Inflammation by Modulating the JNK and IKKβ/NF-κB Pathways in Epididymal White Adipose Tissue of Mice on a High-Fat Diet.

Obesity is associated with insulin resistance (IR), which is characterized by endoplasmic reticulum (ER) stress in multiple organs. ER stress in adipose tissue causes metabolic disturbances and activates inflammatory signaling pathways. Puerarin, an isoflavone extracted from Pueraria lobata, exhibits antioxidant, anti-inflammatory, and antidiabetic effects. This study explores the potential mechanisms underlying puerarin's role in mitigating insulin resistance in high-fat diet (HFD)-induced obese mice. In this study, insulin resistant in mice is induced by a high-fat diet, followed by treatment with puerarin. The results demonstrate that puerarin effectively attenuates insulin resistance, including weight loss, improvement of glucose tolerance and insulin sensitivity, and activation of insulin signaling pathway. Additionally, puerarin administration suppresses ER stress by down-regulation of ATF6, ATF4, CHOP, GRP78 expressions in epididymal white adipose tissue (eWAT), along with decreased phosphorylation IRE1α, PERK, and eIF2α. Furthermore, puerarin exerts anti-inflammatory effects by inhibiting JNK and IKKβ/NF-κB pathways, leading to reduction of TNF-α and IL-6. These findings suggest that puerarin mitigates insulin resistance by inhibiting ER stress and suppressing inflammation through the JNK and IKKβ/NF-κB pathways. This highlights the promising clinical application of puerarin in the treatment of insulin resistance.

Melatonin as a radioprotective agent against flattening filter and flattening filter-free beam in radiotherapy-induced lung tissue damage

Background Radiotherapy is a widely used treatment method in oncology, applied by delivering high-energy particles or waves to the tumor tissue. Although tumor cells are targeted with radiotherapy, it can cause acute or long-term damage to healthy tissues. Therefore, the preservation of healthy tissues has been an important subject of various scientific researches. Melatonin has been shown to have a radioprotective effect on many tissues and organs such as liver, parotid gland, brain, and testicles. This study aimed to evaluate the protective effect of melatonin against the radiation at various doses and rates administered to the lung tissue of healthy mice. Methods This study was a randomized case-control study conducted with 80 rats comprising 10 groups with eight animals per group. Of the 10 groups, first is the control group, which is not given any melatonin, and second is the group that does not receive RT, which is given only melatonin, and the other eight groups are RT groups, four with melatonin and four without melatonin. Results There was no statistical difference in terms of histopathological findings in the lung tissue between the second group, which did not receive radiotherapy and received only melatonin, and the control group. Lung damage due to radiotherapy was statistically significantly higher in the groups that did not receive melatonin compared to the groups that received melatonin. Conclusions This study revealed that melatonin has a protective effect against the cytotoxic damage of RT in rats receiving RT.

PTPN22 through the regulation of Th17/Treg balance acts as a potential target for the treatment of Graves' disease

Graves' disease (GD) is an autoimmune disease and the most common cause of hyperthyroidism. While the phosphotyrosine phosphatase non-receptor type 22 (PTPN22) variant is associated with GD susceptibility, its precise role and mechanism in GD remain unclear. To investigate this, we induced GD in mice using Ad-TSHR289 and isolated CD4+ T cells from spleen tissues. We conducted a series of experiments, including hematoxylin-eosin staining, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, flow cytometry, immunofluorescence (IF), reverse transcription quantitative PCR (RT-qPCR), and western blotting. PTPN22 expression was found to be downregulated in GD mice. Overexpression of PTPN22 ameliorated pathological damage and increased serum levels of T4 and thyroid stimulating hormone receptor antibody (TRAb), as well as the ratio of thyroid weight to body weight in GD mice. Furthermore, GD mice exhibited elevated levels of CD4+ and IL-17+ T cells, an increased Th17/Treg ratio, and upregulation of IL-17A mRNA expression. Conversely, there was a decrease in Foxp3+ T cells and transcriptional levels of Foxp3, which were reversed by PTPN22 overexpression. In vitro experiments showed that PTPN22 overexpression in CD4+ T cells from spleen tissues of GD mice enhanced Foxp3 expression while reducing IL-17A expression. Mechanistically, PTPN22 overexpression led to decreased levels of phosphorylated Lck (p-Lck), Lck, phosphorylated Fyn (p-Fyn), Fyn, phosphorylated Zap70 (p-Zap70), and Zap70 in both in vivo and in vitro GD models. In summary, PTPN22 can alleviate thyroid dysfunction in GD by modulating Th17/Treg balance through the downregulation of the Lck/Zap70 signaling axis.

Determination of doxorubicin in plasma and tissues of mice by UPLC-MS/MS and its application to pharmacokinetic study

A rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the simultaneous determination of doxorubicin (DOX) in mouse plasma and tissues, including the heart, liver, spleen, lung, kidney and tumor, and to investigate the pharmacokinetics and distribution in mice. In this study, daunorubicin (DNR) was used as an internal standard, and the mobile phase consisted of ammonium formate 2 mM containing 0.1 % formic acid (A) and acetonitrile (B), the chromatographic column was ACQUITY UPLC BEHTM C18 with a gradient elution at a flow rate of 0.2 mL/min. Electrospray ionization (ESI) in positive ion pattern was utilized for the ion separation of DOX, with the ions used for quantitative analysis being DOX m/z 544.28 → 397.10 and DNR m/z 528.35 → 321.08, respectively. The results showed that a good linear relationship in the calibration curve range of 1–800 ng/mL in mouse plasma and 1–2500 ng/g in tissues (R2 > 0.99) with the limits of quantification of 1 ng/mL in plasma and tissues. The method exhibited good matrix effect and extraction recovery, with the intra-day and inter-day precision of plasma and tissue were less than 10.3 % and 15.4 %, and the relative error (RE) were both less than ±14.8 % and ±18.9 %, respectively. The stability results under different conditions were found to be accurate. It also revealed the distribution of DOX in various tissues of mice, with the concentration ranking as liver > heart > kidney > spleen > lung > tumor. This method was successfully used to the study for the pharmacokinetics in plasma and drug distribution in tissues of BALB/c mice.

Novel 99mTc-Labeled Mannose Derivative as a Highly Promising Single Photon Emission Computed Tomography Probe for Tumor Imaging.

18F-2-fluoro-2-deoxy-d-glucose ([18F]FDG) has been the most used positron emission tomography imaging agent for clinical applications. Single photon emission computed tomography (SPECT) imaging is cheaper and used more widely for diagnostic use, but there is no SPECT tumor imaging agent for clinical applications comparable to [18F]FDG. Mannose is a C2 epimer of glucose and can also be transported into tumor cells via glucose transporters (GLUTs). To develop a novel SPECT tumor imaging agent with satisfactory tumor uptake and tumor/nontarget ratios, here a mannose derivative (CN7DM) was synthesized and radiolabeled with technetium-99m to prepare [99mTc]Tc-CN7DM. The six-coordinated structure of [99mTc]Tc-CN7DM was confirmed by the corresponding rhenium compound (Re-CN7DM). [99mTc]Tc-CN7DM was transported into cancer cells via GLUTs and may be trapped in the cancer cells by electrostatic attraction. The probe exhibited high uptake in tumors and low uptake in nontarget tissues in mice bearing different tumors, indicating that [99mTc]Tc-CN7DM exhibited promising potential for SPECT tumor imaging and warranted further clinical investigation.