Objective To observe the effect of a heavy load exercise on the ultrastructure,function and fission of skeletal muscle mitochondria in rats,and to analyze the changes of the phosphorylation expression of mitochondrial fission protein and upstream kinase at different times postexercise,and to explore the effect of acute heavy load exercise on mitochondrial fission in skeletal muscle of rats and its possible mechanism.Methods Forty-eight adult male Sprague-Dawley rats were randomly divided in-to a quiet control group(C,n=8)and an exercise group(E,n=40).Rats in the E group exercised on a treadmill down a 16° decline at 16 m/min for 90 min and were further divided into 0 h,12 h,24 h,48 h,and 72 h postexercise subgroups.Soleus muscle was isolated and mitochondria were ex-tracted at the corresponding time points after exercise.The ultrastructure of mitochondria in the soleus muscle was observed using transmission electron microscopy,and mitochondrial quantity and morphomet-ric analysis were conducted.Moreover,the colocalization and quantity of dynamin-related protein 1(Drp1)and cytochrome C oxidease subunit Ⅳ(COXⅣ)in the soleus muscle were detected using im-munofluorescence double-labeling techniques.Meanwhile,protein levels of soleus musclep-Drp1Ser616,p-Drp1Ser637,p-extracellular regulatory protein kinaseThr202/Tyr204(p-ERKThr202/Tyr204),p-protein kinaseAThr197(p-PKAThr197),and mitochondrial NADH of ubiquinone oxidoreductase subunit B8(NDUFB8)and ubiqui-nol-cytochrome C reductase core protein 2(UQCRC2)were determined by using Western blotting.An-other twenty-four rats were randomly divided into a DMSO group(CD),a U0126 group(CU),an Ex-ercise+DMSO group(ED),and an Exercise+U0126 group(EU).Six mice in each group were giv-en a single intra-bitoneal injection of DMSO or ERK inhibitor U0126 20 min before acute downhill running.Then,their phosphorylated expressions of ERKThr202/Tyr204 and Drp1Ser616 in soleus muscle were de-tected by Western blotting.Results(1)From 0 h to 48 h after exercise,the soleus muscle mitochon-dria showed swelling,rounding,and uneven distribution of mitochondria,among which the degree of mitochondrial damage was the most serious at 12 h and 24 h after exercise.Moreover,the protein ex-pression of NDUFB8 and UQCRC2 in the mitochondria fractions from soleus muscle was significantly lower at 12 h post-exercise(P<0.05).(2)The co-localization of Drp1 and COXⅣ in the skeletal muscle increased significantly at 12 h to 24 h after a heavy load exercise compared with group C and group E0(P<0.01).Moreover,the mitochondrial area,circumference,aspect ratio and Ferret diameter in the skeletal muscle were significantly lower at 12 h to 24 h postexercise(P<0.05).Meanwhile,the number of mitochondria was significantly higher at 24 h after exercise(P<0.01).(3)The phosphoryla-tion of ERKThr202/Tyr204,PKAThr197 and Drp1Ser616 was significantly higher at 24 h after exercise(P<0.01),while that of Drp1Ser637 was significantly lower at 48 h and 72 h post-exercise(P<0.01).However,the phosphorylated expressions of ERKThr202/Tyr204 and Drp1Ser616 were significantly down-regulated by U0126 treatment before exercise.Conclusion A session of heavy load exercise caused mitochondrial structure and function damage and induced mitochondrial fission in the skeletal muscle,and then to maintain the homeostasis of skeletal muscle cells by cleaving damaged mitochondria.The mechanism of promot-ing skeletal muscle repair may be related to the positive and negative regulation of Drp1 activity by the phosphorylation of Drp1Ser616 and Drp1Ser637,respectively.Among them,the activation of ERKThr202/Tyr204 mediates the phosphorylation activation of Drp1Ser616,but PKAThr197 is not an upstream kinase that medi-ates the inactivation of Drp1Ser637 phosphorylation.

Oral squamous cell carcinoma is a common malignant tumor of the head and neck.Early surgery can achieve good results,but most patients have cervical lymph node metastasis at the time of initial diagnosis.Although surgery combined with radiotherapy or chemotherapy can delay the progression of the disease,the overall prognosis is still not ideal.Especially in patients at stage Ⅲ/Ⅳ,the long-term survival rate has not improved.As a key microbubble in intercellular communication,exosomes contain a large number of biological molecules such as nucleic acids,proteins and lipids.Tumor-derived exosomes play a key role in regulating the tumor micro-environment.This article reviews the effects of tumor-derived exosomes on tumor proliferation,metastasis,immune regulation,diagnosis and treatment in oral squamous cell carcinoma,in order to provide new ideas for early diagnosis and treatment of oral cancer.

Objective To observe the effect of a heavy load exercise on the ultrastructure,function and fission of skeletal muscle mitochondria in rats,and to analyze the changes of the phosphorylation expression of mitochondrial fission protein and upstream kinase at different times postexercise,and to explore the effect of acute heavy load exercise on mitochondrial fission in skeletal muscle of rats and its possible mechanism.Methods Forty-eight adult male Sprague-Dawley rats were randomly divided in-to a quiet control group(C,n=8)and an exercise group(E,n=40).Rats in the E group exercised on a treadmill down a 16° decline at 16 m/min for 90 min and were further divided into 0 h,12 h,24 h,48 h,and 72 h postexercise subgroups.Soleus muscle was isolated and mitochondria were ex-tracted at the corresponding time points after exercise.The ultrastructure of mitochondria in the soleus muscle was observed using transmission electron microscopy,and mitochondrial quantity and morphomet-ric analysis were conducted.Moreover,the colocalization and quantity of dynamin-related protein 1(Drp1)and cytochrome C oxidease subunit Ⅳ(COXⅣ)in the soleus muscle were detected using im-munofluorescence double-labeling techniques.Meanwhile,protein levels of soleus musclep-Drp1Ser616,p-Drp1Ser637,p-extracellular regulatory protein kinaseThr202/Tyr204(p-ERKThr202/Tyr204),p-protein kinaseAThr197(p-PKAThr197),and mitochondrial NADH of ubiquinone oxidoreductase subunit B8(NDUFB8)and ubiqui-nol-cytochrome C reductase core protein 2(UQCRC2)were determined by using Western blotting.An-other twenty-four rats were randomly divided into a DMSO group(CD),a U0126 group(CU),an Ex-ercise+DMSO group(ED),and an Exercise+U0126 group(EU).Six mice in each group were giv-en a single intra-bitoneal injection of DMSO or ERK inhibitor U0126 20 min before acute downhill running.Then,their phosphorylated expressions of ERKThr202/Tyr204 and Drp1Ser616 in soleus muscle were de-tected by Western blotting.Results(1)From 0 h to 48 h after exercise,the soleus muscle mitochon-dria showed swelling,rounding,and uneven distribution of mitochondria,among which the degree of mitochondrial damage was the most serious at 12 h and 24 h after exercise.Moreover,the protein ex-pression of NDUFB8 and UQCRC2 in the mitochondria fractions from soleus muscle was significantly lower at 12 h post-exercise(P<0.05).(2)The co-localization of Drp1 and COXⅣ in the skeletal muscle increased significantly at 12 h to 24 h after a heavy load exercise compared with group C and group E0(P<0.01).Moreover,the mitochondrial area,circumference,aspect ratio and Ferret diameter in the skeletal muscle were significantly lower at 12 h to 24 h postexercise(P<0.05).Meanwhile,the number of mitochondria was significantly higher at 24 h after exercise(P<0.01).(3)The phosphoryla-tion of ERKThr202/Tyr204,PKAThr197 and Drp1Ser616 was significantly higher at 24 h after exercise(P<0.01),while that of Drp1Ser637 was significantly lower at 48 h and 72 h post-exercise(P<0.01).However,the phosphorylated expressions of ERKThr202/Tyr204 and Drp1Ser616 were significantly down-regulated by U0126 treatment before exercise.Conclusion A session of heavy load exercise caused mitochondrial structure and function damage and induced mitochondrial fission in the skeletal muscle,and then to maintain the homeostasis of skeletal muscle cells by cleaving damaged mitochondria.The mechanism of promot-ing skeletal muscle repair may be related to the positive and negative regulation of Drp1 activity by the phosphorylation of Drp1Ser616 and Drp1Ser637,respectively.Among them,the activation of ERKThr202/Tyr204 mediates the phosphorylation activation of Drp1Ser616,but PKAThr197 is not an upstream kinase that medi-ates the inactivation of Drp1Ser637 phosphorylation.

Oral squamous cell carcinoma is a common malignant tumor of the head and neck.Early surgery can achieve good results,but most patients have cervical lymph node metastasis at the time of initial diagnosis.Although surgery combined with radiotherapy or chemotherapy can delay the progression of the disease,the overall prognosis is still not ideal.Especially in patients at stage Ⅲ/Ⅳ,the long-term survival rate has not improved.As a key microbubble in intercellular communication,exosomes contain a large number of biological molecules such as nucleic acids,proteins and lipids.Tumor-derived exosomes play a key role in regulating the tumor micro-environment.This article reviews the effects of tumor-derived exosomes on tumor proliferation,metastasis,immune regulation,diagnosis and treatment in oral squamous cell carcinoma,in order to provide new ideas for early diagnosis and treatment of oral cancer.

Objective To explore the effect of 4-week repetitive downhill treadmill running on the mi-tochondrial structure,function,and autophagy in skeletal muscle of rats,so as to analyze the role of FKBP8-mediated mitophagy in exercise-induced mitochondrial damage in their skeletal muscles.Meth-ods Thirty-two male adult Sprague-Dawley rats were randomly divided into a 2-week quiet control group(2C group,n=8),a 4-week quiet control group(4C group,n=8),a 2-week exercise group(2E group,n=8)and a 4-week exercise group(4E group,n=8).Rats in 2E and 4E groups performed dai-ly 90-minute downhill treadmill running(-16°,16 m/min)5 days a week for two and four weeks,re-spectively.Then,they rested for 24 hours and received an exhaustive exercise test.Running distance and blood lactate were measured prior to and at the time of exercise cessation.Moreover,mitochondri-al ultrastructural changes in soleus muscles were observed by using a transmission electron microscope.The protein expression of mitochondrial succinate dehydrogenase subunit B(SDHB),cytochrome C oxi-dase subunit 1(MTCO1),FK506 binding protein 8(FKBP8)and microtubule associated protein 1 light chain 3(LC3)in the soleus muscle were measured using Western blotting.Meanwhile,the co-localiza-tion of FKBP8 with LC3 and cytochrome C oxidase subunit Ⅳ(COXⅣ)with LC3,lysosomal associat-ed membrane protein 2(LAMP2)were detected by the immunofluorescence double labeling technique.Results(1)The running distance of one exhaustive exercise and the blood lactate before and after the test in 2E group were significantly higher than 2C and 4E groups(P<0.05 or P<0.01),and the run-ning distance of 4E group was significantly higher than 4C group(P<0.01).However,there was no sig-nificant difference between 4E and 4C groups in the blood lactate before and after the exhaustive exer-cise test(P>0.05).(2)In both 2E and 4E groups,significant mitochondrial swelling and accumulation under cell membrane,as well as a number of mitophagosomes and mitophagolysosomes were observed,together with a significant reduce in the number of mitochondria(P<0.05),which was more severe in 2E group than 4E group.(3)The protein expression of mitochondrial SDHB and MTCO1 in 2E and 4E groups were lower than 2C and 4C groups,respectively,with significantly greater changes of these proteins in 4E group than 2E group(P<0.05 or P<0.01).(4)The protein expression of mitochondrial FKBP8 and LC3,as well as the co-localization of FKBP8 with LC3 and COXⅣ with LC3,LAMP2 in 2E and 4E groups were higher than 2C and 4C groups,respectively,with significantly greater changes in 4E group than 2E group(P<0.05 or P<0.01).Conclusion After 4-week downhill treadmill running,the structure,quantity and function of mitochondria in skeletal muscle are impaired.FKBP8-mediated mitophagy is activated,but is insufficient to degrade the damaged mitochondria,leading to muscular damage,as well as the increasing and falling down of running capacity.

Mitochondrial quality control plays an important role in maintaining homeostasis of mitochondrial network and normal function of mitochondria. ATPase family AAA domain-containing protein 3A (ATAD3A) is one of the mitochondrial membrane proteins involved in the regulation of mitochondrial structure and function, mitochondrial dynamics, mitophagy and other important biological processes. Recent studies show that ATAD3A not only interacts with Mic60/Mitofilin and mitochondrial transcription factor A (TFAM) to maintain mitochondrial cristae morphology and oxidative phosphorylation, but also interacts with dynamin-related protein 1 (Drp1) to positively/negatively regulate mitochondrial fission. In addition, ATAD3A serves as a bridging factor between the translocase of the outer mitochondrial membrane (TOM) complex and translocase of the inner mitochondrial membrane (TIM) complex to facilitate the import of PTEN-induced putative kinase protein 1 (PINK1) into mitochondria and its processing displays a pro-autophagic or anti-autophagic activity. This article reviews the role and mechanism of ATAD3A in regulating mitochondrial quality control. Firstly, as an inner mitochondrial membrane protein, ATAD3A is involved in maintaining the stability of mitochondrial crista structure, and its gene deletion or mutation will cause the loss and breakage of crista. Secondly, ATAD3A is also involved in maintaining mitochondrial respiratory function and mitochondrial nucleoid homeostasis, and its gene deletion or mutation can reduce the activity of mitochondrial respiratory chain complex and enhance the size and movement of nucleoid. Thirdly, ATAD3A participates in the negative regulation of mitochondrial fusion, but its role in mitochondrial fission may dependent on specific cell types, as it can promote and/or inhibit the mitochondrial fission by increasing and/or decreasing phosphorylation or oligomerization of Drp1. Finally, ATAD3A can interact with mitophagy-related proteins (e.g. PINK1, autophagy/beclin-1 regulator 1 (AMBRA1), acylglycerol kinase (AGK)) to enhance/reduce PINK1-Parkin-dependent mitophagy.

【Objective】 To investigate the effects of preoperative ureteroscopy (URS) on the intravesical recurrence (IVR) in patients with upper tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). 【Methods】 The clinical data of 241 UTUC patients treated during May 2012 and Jan.2020 in the Second Hospital of Laozhou University were retrospectively analyzed. The patients were divided into URS before RNU group (URS group) and non-URS before RNU group (non-URS group). The cumulative IVR rate, progression-free survival (PFS) and overall survival (OS) after RNU were compared, and the survival curve was drawn. Cox proportional hazards models were used to assess risk factors affecting IVR. 【Results】 Of the 241 patients, 64 (26.6%) were included in the URS group and 177 (73.4%) in the non-URS group. In the URS group, 49 underwent biopsy and 15 did not. All patients were followed up for a median of 44 (3 to 122) months, with a median time to recurrence of 12 (3 to 56) months. IVR occurred in 18 patients (28.1%) in the URS group and 25 (14.1%) in the non-URS group. Kaplan-Meier survival analysis showed that the cumulative IVR rate was higher in the URS group than in the non-URS group (all P<0.05), regardless of whether patients had a history of bladder cancer (BC) or not, while PFS was lower in the URS group than in the non-URS group (P=0.007). Cox multivariate regression analysis showed that URS (P=0.031) and complicated renal pelvis tumor and ureteral tumor (P=0.004) were independent risk factors for IVR. 【Conclusion】 Preoperative URS increases the incidence of IVR in patients with UTUC, and routine preoperative use of URS is not recommended.

OBJECTIVE: To evaluate the efficacy and safety of glyceryl phenylbutyrate (GPB) therapy for patients with Ornithine transcarbamylase deficiency (OTCD). METHODS: Two children with OTCD were selected as the study subjects, and their clinical manifestations, blood ammonia, liver enzymes, growth and development information following the treatment with GPB were retrospectively analyzed. A literature review was also carried out by searching the PubMed database for studies on the GPB treatment for urea cycle disorders. RESULTS: With the GPB treatment, the blood ammonia and liver enzyme level in both patients have decreased to the normal range within 3 months. Motor development in child 2 has improved. No adverse reaction was noted, except for transient palmar greasy smell and loss of appetite in child 1. Analysis of the literature showed that patients had lower ammonia exposure, lower annual incidence of hyperammonemic crisis, more actual protein intake and fewer adverse events during GPB treatment. CONCLUSION GPB is safe and effective for the treatment of OTCD.
Child ; Humans ; Ornithine Carbamoyltransferase Deficiency Disease/drug therapy* ; Phenylbutyrates/therapeutic use* ; Ammonia ; Retrospective Studies

Twenty-five compounds of novel quinoxaline-based scaffold with antiplatelet activity were designed and synthesized on the basis of previous quinoxaline analogues, and the structures were confirmed by ¹H NMR, ¹³C NMR, and MS. The antiplatelet activity was evaluated, structure-activity relationship (SAR) study was summarized and the selectivity of PAR4 was confirmed by calcium mobilization assays. It was indicated that compound 14a, 14g, 13i, 13p showed moderate activity against PAR4, especially, the activity of compound 14g (IC₅₀ = 0.26 μmol·L^-1) was 6.7 times than the lead compound A (IC₅₀ = 1.73 μmol·L^-1). Therefore, 2,3-dihydro-[1,4]dioxino[2,3-g]quinoxaline and [1,3]dioxolo[4,5-g]quinoxaline derivatives are promising compounds for the discovery of novel antiplatelet agents. It is worthy of further research to develop highly effective and selective PAR4 antagonists.

Fibroma/diagnostic imaging* ; Humans ; Odontogenic Tumors/diagnostic imaging* ; Tuberous Sclerosis/complications*