[Mitochondrial pyruvate carrier deficiency: 3 cases report and literature review]

Objective: To analyze the clinical and genetic features of patients with mitochondrial pyruvate carrier deficiency (MPYCD). Methods: This was a case series research. The clinical data, genetic characteristics, and glutamine treatment efficacy of 3 patients diagnosed with MPYCD at the Department of Neurology, Beijing Children's Hospital, Capital Medical University and Department of Pediatrics, Guizhou Provincial People's Hospital, from August 2019 to June 2023 were retrospectively collected. A literature search with "MPC1 gene" "MPC2 gene and" "mitochondrial pyruvate carrier deficiency" as keywords was conducted at the Wanfang Data Knowledge Service Platform, China National Knowledge Infrastructure (CNKI) and PubMed (up to June 2023). Clinical and genetic characteristics of patients with MPYCD were summarized. Results: Case 1 was a 3 years and 11 months old boy, while case 2 was a 4 years and 10 months old boy and case 3 was an 8 years and 9 months old girl. Case 2 and case 3 were siblings from one consanguineous family. All 3 patients presented with general developmental delay, growth failure and elevated serum lactate. Cranial magnetic resonance imaging (MRI) showed subtle bilateral symmetrical T2 signal hyperintensity in basal ganglia and thalamus in case 1, but normal in case 2 and 3. Trio-WES revealed case 1 harboring compound heterozygous missense variants c.208G>A (p.Ala70Thr) and c.290G>A (p.Arg97Gln) in MPC1 gene, while case 2 and 3 revealed a homozygous variant c.290G>A (p.Arg97Gln) in the same gene. All 3 cases were diagnosecl as MPYCD. Clinical symptoms including motor ability, cognition and activity endurance were improved in these 3 patients after taking glutamine for 2 years. A total of 5 articles published in English were reviewed, and no Chinese literature was found. Including these 3 cases, 15 cases were enrolled for analysis. Eleven patients carried MPC1 gene variants and 4 cases carried MPC2 gene variants. Except for 3 cases died during prenatal period, 9 of 12 enrolled born cases were onset before 6 months old. The most common clinical symptoms were mental and motor general developmental delay, microcephaly, growth failure and hypotonia. All patients had elevated blood lactate and pyruvate, but the ratio of lactate/pyruvate was normal. Seven patients performed cranial MRI, 3 exhibited non-specific changes, 2 showed bilateral symmetrical T2 signal hyperintensity in basal ganglia and thalamus, and 3 were normal. A total of 5 MPC1 gene missense variants and 2 MPC2 gene variants were identified in 15 cases. Conclusions: Onset age of patients with MPYCD is usually within 6 months. The main clinical characteristics are developmental delay, microcephaly and growth failure, accompanied by increased serum lactate and pyruvate. Glutamine supplement could lead to clinical improvements.

[Clinical effects of superficial temporal artery lobulated perforator flaps in repairing skin and soft tissue defects after temporal tumor resection]

Objective: To explore the feasibility and clinical effects of using superficial temporal artery lobulated perforator flaps in repairing skin and soft tissue defects after tumor resection in the temporal region. Methods: A retrospective observational study method was used. From March 2017 to October 2022, ten patients with temporal skin tumors were admitted to the Affiliated Hospital of Zunyi Medical University, including six women and four men, with age ranging from 42 to 87 years. Among them, three patients had squamous cell carcinoma and seven patients had basal cell carcinoma, with disease duration ranging from 6 months to 5 years. All temporal tumors underwent expanded resection, leaving wound areas of 5.4 cm×4.2 cm to 7.0 cm×4.0 cm after tumor resection. Superficial temporal artery frontal branch flaps with areas of 5.5 cm×1.2 cm to 7.0 cm×1.5 cm, superficial temporal artery descending branch flaps with areas of 4.2 cm×3.5 cm to 5.0 cm×4.0 cm, and superficial temporal artery parietal branch flaps with areas of 4.2 cm×1.0 cm to 5.0 cm×1.0 cm were designed to repair the wounds and reconstruct the hairline. The donor areas of the flaps were closed and sutured directly. The survival of the flaps was observed on 3 to 5 days after surgery, and the healing of wounds on the donor and recipient sites was observed when the stitches were removed on 5 to 7 days after surgery. During follow-up after surgery, the appearance of the temporal area, scar hyperplasia, hairline reconstruction, and tumor recurrence were observed in the temporal region on the affected side. Results: All the flaps survived well on 3 to 5 days after surgery, and all the donor and recipient site wounds healed well on 5 to 7 days after surgery. During follow-up of 3 to 6 months after surgery, the surgical incisions were concealed; the flaps were not swollen, with a consistent color to the surrounding skin; there were no obvious hypertrophic scars; the reconstructed hairline on the affected side was not significantly different from that of the healthy side; there was no tumor recurrence in the local area. Conclusions: For large areas of skin and soft tissue defects in the temporal region, the use of superficial temporal artery lobulated perforator flaps can repair the wounds in different regions and suture the donor sites in the primary stage simultaneously. The surgical operation is simple, and the facial appearance conforms to the aesthetic requirement after surgery with no tumor recurrence in the local area but a good repair effect. This method is particularly suitable for repairing large areas of skin and soft tissue defects in the temporal region in elderly patients.

[Reliability and validity of the Chinese version of adverse childhood experiences international questionnaire in parents of preschool children]

OBJECTIVE

To test the reliability and validity of the Chinese version of adverse childhood experiences international questionnaire (ACE-IQ) in Chinese parents of preschool children.

METHODS

The parents of preschool children in 6 kindergartens in Tongzhou District of Beijing were selected by stratified random cluster sampling, and the Chinese version of ACE-IQ after translation and adaptation was used for survey online. The collected data were randomly divided into two parts. One part of the data (n=602) was used for exploratory factor analysis (EFA), to screen items and evaluate structural validity, and then form the final Chinese version of ACE-IQ. The other part of the data (n=700) was used for confirmatory factor analysis (CFA), criterion validity analysis and reliability analysis. At the same time, experts investigation method was used to evaluate the content validity of the final Chinese version of ACE-IQ.

RESULTS

After deleting four items of collective violence, the Chinese version of ACE-IQ with twenty-five items indicated good structural, criterion and content validity. Analysis results showed that the Chinese version of ACE-IQ presented a seven-factor model dimension, namely emotional neglect, physical neglect, family dysfunction, family violence, emotional and physical abuse, sexual abuse and violence outside the home, and the total score of the binary version of ACE-IQ Chinese version was positively correlated with the total score of childhood trauma questionaire-28 item short form (CTQ-SF, r=0.354, P < 0.001) and the center for epidemiological studies depression scale (CES-D, r=0.313, P < 0.001) respectively. Results from five experts showed that the item-level content validity index (I-CVI) of 25 items was between 0.80 and 1.00, and the average of all I-CVIs on the scale (S-CVI/Ave) of the scale was 0.984. At the same time, the internal consistency (Cronbach's α coefficient) of the whole scale was 0.818, and the split-half reliability (Spearman-Brown coefficient) was 0.621, which demonstrated good reliability.

CONCLUSION

This study has formed a Chinese version of ACE-IQ with 25 items and 7 dimensions, which has good reliability and validity among the parents of preschool children in China. It can be used as an evaluation instrument for measuring the minimum threshold of the adverse childhood experiences in the parents of preschool children in the cultural background of China.

Specific Overexpression of YAP in Vascular Smooth Muscle Attenuated Abdominal Aortic Aneurysm Formation by Activating Elastic Fiber Assembly via LTBP4

Abdominal aortic aneurysm (AAA) is a fatal vascular disease. Vascular smooth muscle cells (VSMCs) play a crucial role in the pathogenesis of AAA. Increasing evidence has shown that Yes-associated protein (YAP) is involved in diverse vascular diseases. However, the role of YAP in AAA remains unclear. The current study aimed to determine the role of YAP in AAA formation and the underlying mechanism. We found that YAP expression in VSMCs was markedly decreased in human and experimental AAA samples. Furthermore, VSMC-specific YAP overexpression prevented several pathogenic factor-induced AAA. Mechanistically, YAP overexpression in VSMCs promoted latent transforming growth factor-β binding protein 4 (LTBP4) expression, an important factor in elastic fiber assembly. Finally, silencing of LTBP4 in VSMCs abolished the protective role of YAP in AAA formation in vivo. Our results suggest that YAP promotes LTBP4-mediated elastic fibril assembly in VSMCs, which mitigates elastin degradation and AAA formation.

[Comparative study of unilateral biportal endoscopy and coaxial large channel endoscopy for lumbar spinal stenosis]

Objective: To compare the efficacy of unilateral biportal endoscopy (UBE) and coaxial large channel endoscopy for lumbar spinal stenosis. Methods: A total of 176 patients with lumbar spinal stenosis treated in Tianjin Hospital from March 2015 to October 2021 were included in this study. Of the patients, 110 cases were treated with UBE, including 52 males and 58 females, with a mean age of (75.1±10.4) years; while 66 cases were treated with coaxial large channel endoscopy, including 31 males and 35 females, with an average age of (77.2±13.1) years. The visual analogue scale (VAS) score of pain and Oswestry disability index (ODI) were compared before and after surgery between the two groups, with the improvement rate calculated. The operation time, intraoperative blood loss, perioperative conditions and complications were compared. The operation efficacy was evaluated according to MacNab scale and was compared between the two groups. Results: There was no significant differences in age, gender, disease course, VAS of pain, ODI and index levels between the two groups before operation (all P>0.05). The operation time and postoperative drainage in UBE group and coaxial large channel endoscopy group were comparable [(60.1±12.4)min, (62.5±13.2)min and (103.8±20.7)ml, (98.5±22.1)ml, respectively, both P>0.05]. After the operation, the VAS score of low back pain, VAS score of leg pain and ODI of the two groups were all lower than those before operation, and decreased continuously during follow-up; and under the repeated measures analysis of variance, significant differences were found between different time points (all P<0.05), no significant difference was found between the two groups (all P>0.05), nor interaction between groups and time points was detected (all P>0.05). The patients were followed-up for (18.0±4.2) months (6 to 30 months). There was no significant difference in VAS and ODI improvement rates and excellent rate of efficacy between the two groups at the last follow-up (all P>0.05). Conclusions: Both UBE and coaxial large channel endoscopy can provide excellent results for lumbar spinal stenosis. UBE has sufficient decompression and is convenient to explore and remove the herniated disc.

Brown Adipose Tissue Activation Is Involved in Atherosclerosis of ApoE-/- Mice Induced by Chronic Intermittent Hypoxia

Background: Obstructive sleep apnea is an atherogenesis factor of which chronic intermittent hypoxia is a prominent feature. Chronic intermittent hypoxia (CIH) exposure can sufficiently activate the sympathetic system, which acts on the β3 adrenergic receptors of brown adipose tissue (BAT). However, the activity of BAT and its function in CIH-induced atherosclerosis have not been fully elucidated.

Methods: This study involved ApoE^−/− mice which were fed with a high-fat diet for 12 weeks and grouped into control and CIH group. During the last 8 weeks, mice in the CIH group were housed in cages to deliver CIH (12 h per day, cyclic inspiratory oxygen fraction 5–20.9%, 180 s cycle). Atherosclerotic plaques were evaluated by Oil Red O, hematoxylin and eosin, Masson staining, and immunohistochemistry. Afterward, we conducted immunohistochemistry, western blotting, and qRT-PCR of uncoupling protein 1 (UCP1) to investigate the activation of BAT. The level of serum total cholesterol (TC), triglyceride, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), and free fatty acid (FFA) were measured. Finally, RNA-Sequencing was deployed to explore the differentially expressed genes (DEGs) and their enriched pathways between control and CIH groups.

Results: Chronic intermittent hypoxia exposure promoted atherosclerotic plaque area with increasing CD68, α-SMA, and collagen in plaques. BAT activation was presented during CIH exposure with UCP1 up-regulated. Serum TC, triglyceride, LDL-c, and FFA were increased accompanied by BAT activation. HDL-c was decreased. Mechanistically, 43 lipolysis and lipid metabolism-associated mRNA showed different expression profiling between the groups. Calcium, MAPK, and adrenergic signaling pathway included the most gene number among the significantly enriched pathways.

Conclusion: This study first demonstrated that BAT activation is involved in the progression of CIH-induced atherosclerosis, possibly by stimulating lipolysis.

[Early onset epileptic encephalopathy caused by mitochondrial arginyl-tRNA synthetase gene deficiency: report of two cases and literature review]

Objective: To summarize the clinical features of two early onset epileptic encephalopathy (EOEE) patients with arginyl-tRNA synthetase (RARS2) gene variations and to review related literature. Methods: The clinical data and genetic features of two pontocerebellar hypoplasia type 6 (PCH6) patients with RARS2 variation diagnosed by the Department of Neurology, Beijing Children's Hospital from January 2017 to December 2018 were analyzed retrospectively. A literature search with "RARS2" "pontocerebellar hypoplasia type 6" and "early onset epileptic encephalopathy" as key words was conducted at China national knowledge infrastructure (CNKI), Wanfang Data Knowledge Service Platform and PubMed (up to May 2020), literature about RARS2 gene variation patients and their complete clinical data were chosen and reviewed. Results: The onset age of the two cases (1 male, 1 female) were 2 months and 29 days respectively and the early onset symptom of them was epileptic encephalopathy. The main symptoms included seizures, development delay, microcephaly and lactic acidosis. In addition to these symptoms, the female also had dyspnea, hypoglycemia and metabolic acidosis after birth. Brain magnetic resonance imaging (MRI) of the two patients were normal at first. Follow up at four-month (case 1) and eight-month (case 2) MRI showed atrophy of cerebral and cerebellar, but the pons was not affected. All four heterozygous variations in RARS2 gene revealed by whole-exome sequencing (p.Arg560His and p.Arg6His from case 1, p.Arg254Trp and p.Phe5Ser from case 2) were novel. No eligible reports were found in Chinese journals, while 17 reports were found in English literature. Excluded cases with incomplete data together with these two cases, a total of 34 patients from 20 families were found. All patients had developmental delay while 94% (32/34) patients showed the initial symptoms within 3 months, 93% (28/30) patients were diagnosed as epilepsy, 89% (25/28) patients had progressively microcephaly and 52% (16/31) cases did not show the pons atrophy on brain MRI. Twenty of 28 cases (71%) were refractory epilepsy. There were 31 types of gene variations and most of them were missense variations (21/31, 68%). Conclusions: The majority of PCH6 cases caused by RARS2 gene variation show the initial symptoms within 3 months, characterized by EOEE, most of them are refractory epilepsy, accompanied by developmental delay, microcephaly and increased lactic acid. Brain MRI indicates progressive cerebral or pontocerebellar atrophy.

Lipidomics reveals the dynamics of lipid profile altered by omega-3 polyunsaturated fatty acid supplementation in healthy people

Glycerophospholipids (GPs) and sphingolipids (SPs) are important lipid components in the body and play biological functions. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are important nutrients, and their supplements are commonly used for preventing some diseases. However, the effect of n-3 PUFAs on the human glycerophospholipidome and sphingolipidome is unclear. We used targeted lipidomics to study the GP and SP profile of healthy individuals after supplementation with n-3 PUFAs for 3, 7, 14 and 21 days. Fuzzy c-means clustering was used to cluster the lipid species into six classes reflecting different changed-content patterns after n-3 PUFA supplementation. Among the species with significantly changed content, lysophospholipids were the most sensitive; their content started to increase on day 3. The content of phosphatidylserines increased at a later stage. The content of most of the phosphatidylcholines and alkylphosphatidylcholines decreased on day 21. A correlation network analysis of lipid species suggested that some enzymes involved in the metabolism of lysophospholipids and phosphatidylserines were regulated by n-3 PUFAs. Levels of creatine kinase-MB (CK-MB), urea, glucose, triglycerides and total bilirubin were altered by n-3 PUFA at 21 days. Correlation analysis revealed that the level of CK-MB was negatively correlated with those of species in lysophosphatidic acid, lysophosphatidylcholine, lysophosphatidylethanolamine and phosphatidylserine classes, which were increased by n-3 PUFA supplementation. With the analysis in this work, we demonstrated the regular pattern of n-3 PUFAs on GP and SP metabolism, which provides a pharmacological basis for n-3 PUFAs for clinical application.

[Effects of dexmedetomidine on cerebral oxygen saturation and postoperative revival period in elderly patients with ovarian cancer]

Objective: To observe the effects of dexmedetomidine on cerebral oxygen saturation and postoperative recovery in elderly patients with ovarian cancer. Methods: Sixty elderly patients with ovarian cancer were randomly divided into two groups. Both groups were given total intravenous anesthesia. Patients in group D were given a loading dosage of dexmedetomidine 0.5 μg/kg, followed by continuous infusion 0.2 μg·kg(-1)·h(-1) until 30 minutes before the end of operation. Group C were given normal saline at the same time. The cerebral oxygen saturation was observed and recorded before anaesthesia (T0), an hour after operation (T1), the end of operation (T2) and 30 min after tracheal extubation (T3). The time of extubation and adverse reactions such as restlessness, shivering and respiratory inhibition were observed in both groups. Results: There was no significant difference in cerebral oxygen saturation between the two groups at different time points (P>0.05), and the degree of restlessness and its incidence in group D were lower than those in group C, and the adverse reactions such as shivering were lower (P<0.05). Conclusion: Dexmedetomidine has no obvious effect on cerebral oxygen saturation in elderly patients with ovarian cancer. It can effectively prevent and reduce postoperative restlessness, does not affect recovery time, and has fewer adverse reactions.

[A preliminary study on the outcome of lower-risk myelodysplastic syndrome by low-dose decitabine]

目的

评价小剂量地西他滨治疗较低危骨髓增生异常综合征（MDS）患者的初步疗效及安全性，探讨MDS相关基因突变的临床意义。

方法

纳入浙江省4所医院收治的62例较低危MDS患者，治疗分2组，地西他滨组（地西他滨12 mg·m⁻²·d⁻¹，连续5 d）和支持治疗组，检测与MDS预后相关的15项基因突变情况。比较两组患者的总体有效率（ORR）和无进展生存（PFS）时间，分析其与基因突变的相关性。

结果

62例患者中，可评估患者51例，其中地西他滨组24例，支持治疗组27例。与支持治疗组相比，地西他滨组的ORR（66.7%对29.6%，χ²=6.996，P=0.008）和中位PFS时间显著改善（未达到对13.7个月，P=0.037）。51例患者中20例（39.2%）检测到基因突变阳性，其中4例患者单纯SF3B1阳性，均在支持治疗组。与基因突变阴性患者相比，16例基因突变阳性（除单纯SF3B1阳性）患者中位PFS时间显著缩短（9.2个月对18.5个月，P=0.008），其中地西他滨组8例患者中6例有效，支持治疗组无一例（0/8）有效。地西他滨治疗期间主要不良反应为3~4级粒细胞减少（45.8%），3~4级感染发生率为33.3%（8/24）。

结论

该研究小系列患者的初步结果表明应用小剂量地西他滨治疗较低危MDS患者可能有效，对于基因突变患者也可获益，且患者耐受，值得临床试验进一步明确其临床意义。

[Clinical application of oxycodone combined with dexmedetomidine in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas]

Objective: To explore the effects of oxycodone combined with dexmedetomidine in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas. Methods: Sixty patients who underwent percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas were randomly divided into fentanyl group (group A) and oxycodone group( group B), with 30 patients in each group. Patients in group A were injected with fentanyl (2 μg/kg), and patients in group B were injected with oxycodone (0.2 mg/kg). All the patients were injected with dexmedetomidine, with a loading dose of 0.5 μg/kg for 10 minutes and a continuous infusion rate of 0.2 μg·kg(-1)·h(-1) until the end of the operation. The changes of heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SPO(2)) and bispectral index (BIS) were monitored at different time points: time when patients entering the operating room (T0), the beginning of operation (T1), 10 minutes after operation (T2), the end of operation (T3), 15 minutes after the end of operation (T4). The incidence of side effects (nausea and vomiting, respiratory depression and body movements) was assessed. The visual analogue scale (VAS) scores were also recorded at T0, T3 and an hour postoperatively. Results: Five patients of Group A had the body movements during the operation, and it was improved after injecting with fentanyl 2 μg/kg. Compared with T0, HR in two groups decreased significantly at T2 (P<0.05). At each time point, the difference of MAP, HR, SPO(2) and BIS was not statistically significant in two groups. The incidence of Nausea and vomiting, body movements was lower in group B than that in group A(P<0.05). The VAS scores were lower in group B than that in group A at T3 and an hour postoperatively (P<0.05). Conclusion: The combination of oxycodone and dexmedetomidine can be used safely and effectively in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas, and it shows more effective analgesia and less side-effects.

Thoracic Endoscopic-Assisted Mini-Open Surgery for Thoracic and Thoracolumbar Spinal Cord Compression

Intervertebral disc herniation is a common cause of spinal cord compression, especially for the thoracic and thoracolumbar spinal cord, which has limited buffer space in the spinal canal. Spinal cord compression usually causes decreased sensation and paralysis of limbs below the level of compression, urinary and fecal incontinence, and/or urinary retention, which brings great suffering to the patients and usually requires surgical intervention. Thoracotomy or abdominothoracic surgery is usually performed for the thoracolumbar cord compression caused by hard intervertebral disc herniation. However, there is high risk of trauma and complications with this surgery. To reduce the surgical trauma and obtain good visibility, we designed athoracic endoscopic-assisted mini-open surgery for thoracic and thoracolumbar disc herniation, and performed this procedure on 10 patients who suffered from hard thoracic or thoracolumbar spinal cord compression. During the procedure, the thoracic endoscopy provided clear vision of the surgical field with a good light source. The compression could be fully exposed and completely removed, and no nerve root injury or spinal cord damage occurred. All patients achieved obvious recovery of neurological function after this procedure. This technique possesses the merits of minimal trauma, increased safety, and good clinical results. The aim of this study is to introduce this thoracic endoscopic-assisted mini-open surgery technique, and we believe that this technique will be a good choice for the thoracic and thoracolumbar cord compression caused by hard intervertebral disc herniation.

[Predictive and prognostic value of monitoring lymphocyte subsets in peripheral blood before and after chemotherapy in patients with metastatic breast cancer]

OBJECTIVE

To detect the proportion of lymphocyte subsets in peripheral blood of the advanced breast cancer patients before and after chemotherapy with docetaxel and thiotepa, as well as the association between the proportion of peripheral blood lymphocyte subsets with the response rate and prognosis.

METHODS

The proportions of lymphocyte subsets (CD3+ T cell, CD3+/CD4+ T cell, CD3+/CD8+ T cell, CD3-/CD16+56+ NK cell, CD3+/CD16+56+ T cell, CD19+ B cell, CD4+/CD25+ T cell, CD8+/CD28- T cell, CD8+/CD28+ T cell) in the peripheral blood of 86 patients were analyzed with flowcytometry before and after chemotherapy. The result was analyzed in combination with clinicopathological data.

RESULTS

The proportion of regulatory T cells (Treg) after chemotherapy in the disease control patients decreased significantly compared with that of the progressive patients (P=0.034). The difference of the proportions of Treg before and after chemotherapy affected significantly the overall survival (OS). The OS of the patients with decreased proportion of Treg was significantly longer than that of the patients with increased proportion of Treg, which was 23.5 and 9.4 months respectively (P<0.05).

CONCLUSION

The patients with decreased proportion of Treg after chemotherapy had higher response rate and better survival benefit.

Body color development and genetic analysis of hybrid transparent crucian carp (Carassius auratus)

The aim of this study was to investigate the genetic mechanism of the transparent trait in transparent crucian carp. We observed body color development in transparent crucian carp larvae and analyzed heredity of color in hybrids produced with red crucian carp, ornamental carp, and red purse carp. The results showed that the body color of the newly hatched larvae matured into the adult pattern at approximately 54 days post-hatching. Two inter-species reciprocal crosses between transparent crucian carp and red crucian carp, and self-cross F1 of transparent crucian carp and self-cross F1 of red marking transparent crucian carp were conducted, and results indicated that the transparent-scaled trait is dominant over the normal-scaled trait. Furthermore, the transparent trait is a quantitative trait. All offspring in the four inter-genera reciprocal crosses of transparent crucian carp with ornamental carp and red purse carp were hybrids of common carp and crucian carp, and had a relatively low survival rate of 10-20%. Moreover, the transparent-scaled trait was observed to be dominant over the normal-scaled trait in the hybrid fish. In conclusion, our results suggest that the genetic mechanism underlying the color of goldfish is complex and requires further investigation.

Cardiomyocyte-specific loss of diacylglycerol acyltransferase 1 (DGAT1) reproduces the abnormalities in lipids found in severe heart failure

Diacylglycerol acyltransferase 1 (DGAT1) catalyzes the final step in triglyceride synthesis, the conversion of diacylglycerol (DAG) to triglyceride. Dgat1(-/-) mice exhibit a number of beneficial metabolic effects including reduced obesity and improved insulin sensitivity and no known cardiac dysfunction. In contrast, failing human hearts have severely reduced DGAT1 expression associated with accumulation of DAGs and ceramides. To test whether DGAT1 loss alone affects heart function, we created cardiomyocyte-specific DGAT1 knock-out (hDgat1(-/-)) mice. hDgat1(-/-) mouse hearts had 95% increased DAG and 85% increased ceramides compared with floxed controls. 50% of these mice died by 9 months of age. The heart failure marker brain natriuretic peptide increased 5-fold in hDgat1(-/-) hearts, and fractional shortening (FS) was reduced. This was associated with increased expression of peroxisome proliferator-activated receptor α and cluster of differentiation 36. We crossed hDgat1(-/-) mice with previously described enterocyte-specific Dgat1 knock-out mice (hiDgat1(-/-)). This corrected the early mortality, improved FS, and reduced cardiac ceramide and DAG content. Treatment of hDgat1(-/-) mice with the glucagon-like peptide 1 receptor agonist exenatide also improved FS and reduced heart DAG and ceramide content. Increased fatty acid uptake into hDgat1(-/-) hearts was normalized by exenatide. Reduced activation of protein kinase Cα (PKCα), which is increased by DAG and ceramides, paralleled the reductions in these lipids. Our mouse studies show that loss of DGAT1 reproduces the lipid abnormalities seen in severe human heart failure.

Adrenomedullin(27-52) inhibits vascular calcification in rats

Adrenomedullin (ADM) has the vasodilatory properties and involves in the pathogenesis of vascular calcification. ADM could be degraded into more than six fragments in the body, including ADM(27-52), and we suppose the degrading fragments from ADM do the same bioactivities as derived peptides from pro-adrenomedullin. The present study carries forward by assessing the effects on vascular calcification of the systemic administration of ADM(27-52). The rat vascular calcific model was replicated with vitamin D3 and nicotine. ADM or/and ADM(27-52) were systemically administrated with mini-osmotic pump beginning at seventh day after the model replication for 25 days. Vascular calcific nodules histomorphometry, vascular calcium content, vascular calcium uptake, alkaline phosphatase activity, and osteopontin-mRNA quantification in aorta were assessed. ADM limited 40.2% vascular calcific nodules (P<0.01), did not effect on calcium content (P>0.05), reduced 44.4% calcium uptake (P<0.01), lowered 21.1% alkaline phosphatase activity (P<0.01), and regulated 40.9% downwards osteopontin-mRNA expression (P<0.01) in the aorta of rats with vascular calcification. ADM(27-52) receded 32.0% vascular calcific nodules (P<0.01), taken from 55.5% calcium content (P<0.01), did not affect calcium uptake (P>0.05), inhibited 22.5% alkaline phosphatase activity (P<0.01), and restrained 21.9% osteopontin-mRNA expression (P<0.01) in the aorta of rats with vascular calcification. Both of ADM and ADM(27-52) did interact on vascular calcification each other. ADM could partially antagonize the effects of ADM(27-52) in taking from calcium content (17.5%, P<0.01) and in receding vascular calcific nodules (18.6%, P<0.01). ADM could obviously enhance the action of ADM(27-52) in inhibiting alkaline phosphatase activity (14.4%, P<0.01) and in reducing calcium uptake (11.4%, P<0.01). ADM(27-52) could partially antagonize the effects of ADM on regulating downwards osteopontin-mRNA expression (17.0%, P<0.01). It is concluded that ADM(27-52) derived from ADM acts as an inhibitory agent on vascular calcification, with special mechanisms different from ADM derived from ADM progenitor molecule.

Relationship between contents of adrenomedullin and distributions of neutral endopeptidase in blood and tissues of rats in septic shock

Adrenomedullin (ADM), a multifunction peptide with important roles in regulating cardiovascular homeostasis, has the vasodilatory properties and is of particular interest in the pathophysiology of sepsis. ADM levels in plasma and tissues are regulated by the proteolysis of neutral endopeptidase (NEP), the major enzyme of ADM degradation. We observed the NEP activity in the plasma, the activity and distribution of NEP and its mRNA expression in the tissues of rats in septic shock to study the possible role of NEP in elevating tissue ADM concentration during sepsis. ADM level increases progressively during sepsis except in the jejunum. Rats in early phase of shock (ES) showed diverse changes in tissue NEP activity. Plasma NEP activity, tissue NEP activity and its protein and mRNA expression in the left ventricle, aorta, jejunum and lung in the late phase of shock (LS) rats were lower than those in ES and the control, but no statistical change of NEP activity in the kidney was observed. The level of ADM was inversely correlated with NEP activity in the plasma, ventricle and aorta and positively correlated with NEP activity in the jejunum. Thus, in sepsis, the local concentration and action of ADM in tissues may be differentially regulated by NEP.

Changes in production and metabolism of brain natriuretic peptide in rats with myocardial necrosis

In this study, we employed rat model of acute myocardial necrosis induced by isoproterenol (ISO) to study the possible roles of corin, the protease uniquely distributing in myocardium to convert pro-brain natriuretic peptide (proBNP) to BNP, and neutral endopeptidase (NEP), the major enzyme to degrade BNP, in changing the levels of BNP. In rats with isoproterenol alone, the myocardium necrosis occurred and the cardiac function was inhibited; the BNP contents in plasma and myocardium were upregulated, so did the myocardial corin mRNA level; the NEP activity in plasma and myocardium were downregulated. Omapatrilat (OMA) treatment relieved myocardial lesions and improved cardiac function. In the plasma and myocardium, omapatrilat treatment increased BNP contents, reduced NEP activity; in myocardium, mRNA level of proBNP and corin decreased, but NEP mRNA expression increased. Our study confirmed that omapatrilat treated myocardial necrosis effectively and suggested that increased BNP in rats with myocardial necrosis could depend on increased production and conversion as well as decreased degradation.

[Hydrogen sulfide: a novel cardiovascular functional regulatory gas factor]

Hydrogen sulfide (H(2)S) may be endogenously produced by cystathionine beta-lyase (CBS) and cystathionine gamma-lyase (CSE) as a cardiovascular physiological functional factor. On the hypoxic pulmonary hypertension (HPH) animal model, the plasma H(2)S concentration, the gene expression and the activity (CSE) were decreased in lung tissues In L-NAME induced hypertension and spontaneous hypertension rats (SHR) models, the plasma H(2)S concentration, vascular CSE activity and mRNA expression were obviously decreased. When H(2)S was exogenously supplied, systolic pressure obviously decrease. These studies suggested that CSE/H(2)S pathway participated in the pathophysiological development of hypertension. The endogenous level of H(2)S produced by some arterial tissues increased in both septic and endotoxic shock rats. The level of H(2)S highly correlated with the endogenous level of NO. These results suggest that H(2)S may be a novel cardiovascular functional regulator.

Relationship between the Contents of Adrenomedullin and Distributions of Neutral Endopeptidase in Blood and Tissues of Spontaneously Hypertensive Rats

Adrenomedullin (ADM) is a multifunctional peptide with important roles in the cardiovascular system, especially in the adjustment of cardiovascular and renal homeostasis. ADM is present in plasma, organs and tissues, and its activity increases during hypertension. It remains unknown whether the clearance of this peptide is altered during hypertension. Neutral endopeptidase (NEP) is the major enzyme in ADM's degradation. We observed the activity and distribution of NEP and the expression of its mRNA in the plasma, cardiac ventricle, aorta, jejunum and kidney of spontaneously hypertensive rats (SHRs) in order to study the possible role of NEP in elevating tissue ADM concentrations during hypertension. ADM and NEP were diffuse in all tissues studied. The level of tissue ADM was generally higher in SHR tissues than in control tissues, except in the renal medulla, and its mRNA expression was higher in all tissues. Plasma NEP activity, general NEP activity and the expression of NEP mRNA in the left ventricle, aorta and jejunum in SHRs was lower than that of controls, and the level of ADM was inversely correlated with NEP activity. NEP activity and mRNA and protein expression in SHR kidneys were higher than in control kidneys; moreover, the ADM content was positively correlated with NEP activity in the renal cortex. NEP activity in the lung of SHRs did not differ from that of controls. Thus, in SHRs, the local concentration and action of ADM in the tissues may be differentially regulated by NEP.

Dysfunction of myocardial and vascular taurine transport in spontaneously hypertensive rats

The alterations of taurine transport and the expression of taurine transporter (TAUT) mRNA in myocardium and aortic wall were investigated in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. It was demonstrated that plasma taurine concentration and taurine release from myocardium and aortic wall in SHR were higher than those in WKY rats, whereas taurine content, taurine uptake and TAUT mRNA in myocardium and aortic wall of SHR were lower than those of WKY rats. In SHR, the maximal velocity (V(max)) of taurine transportation in myocardium and aortic wall was lower by 24% (P<0.05) and 35% (P<0.05) than that in WKY, their michaelis constants (Km) values were higher by 16% (P<0.05) and 39% (P<0.05), respectively. The results suggest that there is dysfunction of taurine transport in myocardium and aortic wall in SHR, which may be partly resulted from the decrease of TAUT activity and affinity, and down-regulation of TAUT gene expression.

Dysfunction of myocardial taurine transport and effect of taurine supplement in rats with isoproterenol-induced myocardial injury

AIM

To study the alterations of myocardial taurine transport function, taurine transporter (TAUT), and cysteine sulfinate decarboxylase (CSD) mRNA as well as effect of exogenous taurine in rats with isoproterenol (ISO)-induced cardiomegaly.

METHODS

[3H]-Taurine uptake and release on myocardium were determined. Binding sites of [3H]-taurine for myocardial sarcolemma were measured. TAUT and CSD mRNA levels were assayed using competitive quantitative reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

ISO group as compared with control group, myocardial taurine uptake markedly reduced, taurine release obviously increased; Bmax value of [3H]-taurine binding on cardiac sarcolemma reduced by 42% (P<0.05); TAUT and CSD mRNA levels decreased by 40% and 38% (P<0.05), respectively. ISO+taurine group as compared with ISO-treated group, the amounts of taurine uptake and TAUT mRNA returned to normal; taurine release reduced; Bmax increased by 92% (P<0.01), and CSD mRNA content augmented by 23% (P<0.05). There were no statistical differences of Kd values among the four groups (P>0.05).

CONCLUSION

The data indicate that the failure to generate sufficient TAUT on myocardial sarcolemma may be the fundamental abnormality in ISO-induced cardiac injury. The mechanism by which administration of taurine considerably improves ISO-induced cardiac damage is probably to increase the expression of TAUT gene and recover taurine transport function.

[Changes in adrenomedullin and receptor activity-modifying protein 2 mRNA in myocardium and vessels during L-NNA-induced hypertension in rats]

To explore the changes in adrenomedullin (ADM) and receptor activity-modifying protein 2 (RAMP2) mRNA in myocardium and vessels in hypertension, a hypertensive rat model was prepared by administering L-NNA. Contents of ADM in plasma, myocardium and vessels were measured by radioimmunoassay (RIA). The levels of pro-ADM mRNA of myocardium and vessels were determined by competitive quantitative RT-PCR. The results showed that L-NNA induced hypertension and cardiomegaly. The ratio of heart to body weight increased by 35.5% (P<0.01). In hypertensive rats the ir-ADM in plasma, myocardium and vessels was increased by 80%, 72% and 57% (P<0.01), respectively compared with the control. The amounts of ADM mRNA in myocardium and vessels were increased by 50% and 109.2% (P<0.05), respectively, and the amounts of RAMP2 mRNA was increased by 132% and 87% (P<0.01), respectively, compared with control. The levels of ADM in myocardium and vessels were positively correlated with RAMP2 mRNA, the correlation coefficients were 0.741 and 0.885 (P<0.01), respectively. The results obtained indicate that in hypertensive rats, ADM is elevated in plasma, myocardium and ves-myocardium and vessel, and ADM and RAMP2 mRNA are up-regulated in myocardium and vessel. The ADM/RAMP2 system may play an important role in the pathogenesis of hypertension.