Bioassay-guided discovery and identification of new potent α-glucosidase inhibitors from Morus alba L. and the interaction mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Morus alba L. (mulberry) is a well-known medicinal species that has been used by herbalist doctors for the treatment of diabetes for a long history, and modern ethnopharmacological studies have demonstrated the ameliorating effects of different mulberry extracts toward diabetes-related symptoms and identified a number of α-glucosidase inhibitors as hypoglycemic ingredients.

AIM OF THE STUDY

The present study aims to explore new potent α-glucosidase inhibitors from the root bark of M. alba (known as Sang-Bai-Pi in traditional medicine) based on an in vivo antidiabetic evaluation of its extract fractions and further characterize the preliminary mechanism of the new active constituents.

MATERIALS AND METHODS

α-Glucosidase inhibitory assay and diabetic mice model were used to locate and evaluate the active fractions from the extract. Diverse separation techniques (e.g. Sephadex LH-20 column chromatograph (CC) and HPLC) and spectroscopic methods (e.g. MS, NMR and ECD) were employed to isolate and structurally characterize the obtained constituents, respectively. Fluorescence quenching, kinetics and molecular docking experiments were conducted to investigate the enzyme inhibitory mechanism of the active compounds.

RESULTS

The 80% ethanol eluate from the macroporous resin CC exerted good antidiabetic effects in the tested mice. Fifty-two flavonoids including 22 new ones were then separated and identified, and most of them showed strong inhibition against α-glucosidase with their structure-activity relationship being also discussed. The four new most active ingredients were further characterized to be mixed type of α-glucosidase inhibitors, and their binding modes with the enzyme were also explored.

CONCLUSIONS

Our current work has demonstrated that the root bark of M. alba is an extremely rich source of flavonoids as potent α-glucosidase inhibitors and potential antidiabetic agents, which makes it a promising candidate species to develop new natural remedies for the prevention and treatment of diabetes.

[Study on the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A]

Objective: To summarize the resistance of rifampicin-resistant Mycobacterium tuberculosis to anti-tuberculosis drugs in group A. Methods: In the retrospective study, a total of 1 226 clinical isolates from suspected multidrug-resistant pulmonary tuberculosis patients in Beijing TB control system from 2016 to 2021 were identified as Mycobacterium tuberculosis (MTB) strains by MPB64 antigen detection test. Rifampicin-resistant tuberculosis (RR-TB) strains were screened by the phenotypic drug susceptibility using the proportion method. The drug susceptibilities of Levofloxacin(LFX), Moxifloxacin(MFX), Bedaquiline(BDQ) and Linezolid(LZD)were detected by the phenotypic drug susceptibility with microplate method. The drug resistance rate, drug resistance level and minimum inhibitory concentration (MIC) distribution of four anti-tuberculosis drugs in group A were analyzed. We calculated the demographic distribution of RR-TB, multidrug-resistant tuberculosis(MDR-TB), pre-extensively drug resistant tuberculosis (pre-XDR-TB), extensively drug resistant tuberculosis (XDR-TB) patients and the cross resistance of LFX and MFX, then summarized the drug-resistance spectrum of BDQ-resistant and LZD-resistant strains and the treatment outcome of RR-TB patients. Measurement data were expressed as rate or composition ratio,χ2 test was used between and within groups, and P<0.05 was considered statistically significant. Results: Among the 1 226 suspected multidrug-resistant pulmonary tuberculosis patients, the detection rates of RR/MDR/pre-XDR/XDR-TB patients were 20.8%(255/1 226), 15.2%(186/1 226), 5.7%(70/1 226), 0.5%(6/1 226), respectively. There were statistically significant differences in the distribution of patients with the four types of drug resistance in terms of age and treatment history (χ2=14.95, P=0.020;χ2=15.91, P=0.001). The drug resistance rates of LFX, MFX, BDQ and LZD in RR-TB patients were 27.5% (70/255), 27.5% (70/255), 0.4% (1/255) and 2.4% (6/255), respectively. The MICs of LFX, MFX and LZD-susceptible MTB were mainly at 0.25 mg/L, and the MIC of BDQ-susceptible MTB was mainly concentrated at 0.03 mg/L. 25.1% (64/255) of the RR MTB were resistant to both LFX and MFX, and 6 strains were resistant to LFX or MFX, showing incomplete two-way cross resistance. One BDQ-resistant strain and six LZD-resistant strains were detected. The treatment success rate of RR-TB patients was 74.4% (151/203), and there were statistically significant differences in treatment outcomes between resistant and sensitive patients on the LFX-containing treatment regimen (Fisher's exact test, P=0.012). Conclusions: The prevalence of fluoroquinolones (LFX and MFX) resistance in rifampicin-resistant MTB is very serious. LFX and MFX show incomplete bidirectional cross-resistance. BDQ and LZD have the most promising future in the treatment of MDR-TB. Improve drug-resistance testing will help to further improve the success rate of treatment.

Pregnane steroid glycosides with multidrug resistance reversal activity from the stems of Marsdenia tenacissima

Eighteen previously unreported pregnane glycosides, namely marsdenosides S1-S18, along with 15 known analogues, have been isolated from the stems of Marsdenia tenacissima. The structures of the undescribed compounds were elucidated by spectroscopic means, and their absolute configurations were established on the basis of time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation, X-ray crystallography and acid hydrolysis. All the isolates were evaluated for their chemo-reversal ability against P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MCF-7/ADR cell line, and nine ones displayed moderate MDR reversal activity with reversal folds in the range of 2.45-9.01. The most active 12-O-acetyl-20-O-benzoyl-(14,17,18-orthoacetate)-dihydrosarcostin-3-O-β-d-thevetopyranosyl-(1 → 4)-O-β-d-oleandropyranosyl-(1 → 4)-O-β-d-cymaropyranoside increased the sensitivity of MCF-7/ADR cell to adriamycin comparably to the reference drug verapamil (RF = 8.93).

Pregnane steroids and steroid glycosides with multidrug resistance reversal activity from Marsdenia tenacissima

Twenty compounds comprising four pregnane steroids (2-4 &20) and 16 pregnane glycosides (1 &5-19) have been obtained from the ethanol extract of the roots of a Dai ethnological herb, Marsdenia tenacissima. Their structures were characterized on the basis of comprehensive spectroscopic analyses with 17 ones (1-17) being reported for the first time, including the rare cases (2 &3) of free C₂₁ steroids with 17α-acetyl substitution, compounds 4-7 bearing an unusual 14α-OH, and the first examples with simultaneous 14α-OH/17α-acetyl substitution (7) and glycosylation at C-12 position (10 &11). An empirical rule for the identification of C-17 configuration, in C₂₁ steroids incorporating the marsdenin constitution structure, was also proposed. All the isolates, along with an array of previously reported analogues in our compound library, were screened for their chemo-reversal ability against P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MCF-7/ADR cell line, and six compounds exhibited moderate MDR reversal activity with reversal folds ranging from 1.92 to 4.44.

Terrorist Attacks Against Firefighters, 1970-2019

Firefighters are a critical component of the emergency response system and therefore a potential target for organizations seeking to disrupt this system. Terrorist organizations may deliberately attack firefighters to both increase the devastation of an attack and impair the affected community's ability to respond to an attack. We performed a focused search of the Global Terrorism Database to identify terrorist attacks against firefighters worldwide. The database includes incidents from 1970 through 2019, with a total of 201,183 entries. These entries were searched for incidents involving firefighters or fire trucks. We analyzed trends in the number of incidents occurring per year, regions of the world impacted, methods employed, and number of casualties inflicted. A total of 42 attacks involving firefighters were identified in the Global Terrorism Database resulting in 26 deaths and 95 wounded. Of the 42 attacks, 12 (28.6%) were secondary attacks, where firefighters responding to an initial attack were themselves targeted. The most common method for both primary and secondary attacks was the use of a bomb or explosive. Although attacks against firefighters are uncommon, they highlight both the strategic value and vulnerability of firefighters to terrorist attacks. Increased efforts must be made to protect firefighters from future terrorist attacks.

Steroid glycosides from the roots of Marsdenia tenacissima

Eleven undescribed glycosylated C₂₁ steroids and nine known homologous glycosides with diverse acyl substituents, as well as their common steroid aglycone, have been obtained from the roots of Marsdenia tenacissima. Their structures were elucidated mainly by comprehensive spectroscopic analyses and comparison with previously reported analogues, with the absolute configuration assignment being supported by chemical degradation, X-ray crystallography and ECD exciton chirality method. Among them, two pairs of regioisomers were found to exist as inseparable equilibrium mixtures due to an interesting intramolecular transesterification, and nicotinoyl substitution was first reported for metabolites from the title plant. Screening of these compounds in a panel of bioassays revealed that two glycosides displayed mild inhibition against butyrylcholinesterase.

Methyl 2-naphthoates with anti-inflammatory activity from Morinda officinalis

Chemical fractionation of the EtOH extract of the roots of a traditional Chinese herb, Morinda officinalis, afforded an array of methyl 2-naphthoate derivatives (1-9) including four pairs of enantiomers (1-4), two pimarane diterpenes and two ursane triterpenoids. Among them, eight compounds (1a/1b-3a/3b, 11 and 13) were reported in the current work for the first time. The structures of the new compounds, including their absolute configurations, were defined by spectroscopic analyses in combination with quantum chemical electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR calculations. All the isolates were evaluated for their inhibitory effect on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine RAW264.7 macrophage cells, and the enantiomers 1a and 3b exhibited moderate activity with IC₅₀ values of 41.9 and 26.2 μM. Meanwhile, compound 3b also dose-dependently inhibited the secretion of two pro-inflammatory cytokines TNF-α and IL-6 in the same cell model.

[Ferroptosis in laryngeal squamous cell carcinoma and its regulation by M2 macrophage-derived exosomes]

Objective: To investigate ferroptosis in laryngeal squamous cell carcinoma (LSCC) and its regulation by M2 macrophage-derived exosomes. Methods: LSCC and adjacent noncancerous tissue samples were collected from 32 patients treated in the Department of Otorhinolaryngology, Head and Neck Surgery of the Second Affiliated Hospital of Harbin between September 2018 and April 2021, including 26 males and 6 females, aged 43-79 years. The expressions of ferroptosis marker glutathione peroxidase 4(GPX4) in LSCC and adjacent noncancerous tissues were detected by immunohistochemistry and reverse transcriptase-polymerase chain reaction(RT-PCR). The correlations between GPX4 expression and clinicopathological factors in LSCC were analyzed. Biological changes of TU212 cells after treated with ferroptosis-induced agent erastin were detected by transmission electron microscope, cell counting kit-8(CCK-8), clone test, reactive oxygen species(ROS), malondialdehyde(MDA), glutathione(GSH), JC-1, RT-PCR and western blot. Exosomes were isolated from the supernatant of M0/M2 macrophages (M0-exos/M2-exos) and co-incubated with erastin-treated TU212 cells to detect the change of ferroptosis in cells of each group. The data were analyzed by SPSS software of version19.0. Results: GPX4 expression in LSCC tissues was significantly higher than that in adjacent noncancerous tissues (2.04±0.65 vs. 0.99±0.09, F=30.36, P<0.001), and was closely related to T stage and clinical stage (Ⅰ-Ⅱvs.Ⅲ-Ⅳ: 1.75±0.39 vs. 2.18±0.71, F=2.25, P<0.05; T1-2 vs. T3-4: 1.71±0.42 vs. 2.20±0.69, F=2.06, P<0.05). In TU212 cells treated with erastin, mitochondrial crest became smaller, membrane density increased, proliferation rate decreased, intracellular ROS level increased, mitochondrial membrane potential depolarized, GSH content decreased, intracellular MDA level increased and expressions of GPX4 mRNA and protein decreased. Change of M0 into M2 macrophages was induced by IL-4 stimulation. When erastin-treated TU212 cells were incubated with M2-exos, cell proliferation was partially restored and GPX4 expression was enhanced, and also with the recoveries of levels of ROS, MDA and GSH (all P<0.05). Conclusions: Ferroptosis is one of the cell death ways of LSCC. M2-exos may inhibit ferroptosis of LSCC cells.

[Soil denitrifying enzyme activity and its influencing factors in a bamboo forest riparian zone in the upper reaches of the Taihu Lake Basin, China]

Soil denitrifying enzyme activity (DEA) was measured by acetylene inhibition technique, along with exploration of factors influencing DEA in a bamboo forest riparian zone in the upper reaches of the Taihu Lake Basin during summer. Our aim was to provide important insights into the assessment of ecological functions of bamboo forest riparian zone on reducing nitrogen pollution in rivers. The results showed that the riparian soil DEA ranged from 6.32 to 23.22 μg N·kg^-1·h^-1, with a mean value of 14.65 μg N·kg^-1·h^-1. The vertical distribution (0-40 cm soil profile) of DEA was affected by several factors, such as soil organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO₃^--N), soil water content, and activity of carbon and nitrogen hydrolase, which resulted in decreased DEA with increasing soil depth. The horizontal changes in DEA (at the same soil depth but at different distances from river) was mainly governed by the variation in SOC concentration. In this area, the concentration of soil dissolved organic carbon was relatively low, which might inhibit the soil DEA during summer.

[The function and mechanism of long non-coding RNA RP11-159K7.2 in sinonasal squamous cell carcinoma]

Objective: To explore the role and mechanism of long non-coding RNA RP11-159K7.2 in the progression of sinonasal squamous cell carcinoma (SNSCC). Methods: Sixty-five cases of SNSCC tissues and adjacent tissues were selected from the Department of Otorhinolaryngology Head and Neck Surgery, the Second Affiliated Hospital of Harbin Medical University from 2009 to 2014. The expression of RP11-159K7.2 in SNSCC and adjacent tissues was detected by RNAscope in situ hybridization to observe its association with prognosis. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated proteins 9 (CRISPR/Cas9) was used to knockout the expression of RP11-159K7.2 in RPMI-2650 cells (SNSCC cell line). Cell counting kit-8 (CCK-8), wound healing and Transwell were performed to observe the changes of proliferation, migration and invasion of SNSCC cells in vitro after down-regulation of RP11-159K7.2. Moreover, the growth of xenograft in nude mice after down-regulation of RP11-159K7.2 was examined in vivo. Mechanically, the protein chip, Western blot and RNA immunoprecipitation were performed to identify the proteins bound by RP11-159K7.2. SPSS 17.0 was used for statistical analysis. Results: The expression of RP11-159K7.2 in SNSCC tissue was significantly higher than that in adjacent tissues. RP11-159K7.2 expression was closely related with T grade, nodal metastasis and differentiation of SNSCC (χ² value was 4.697, 4.235 and 10.753, respectively, all P<0.05). The five-year survival rate of RP11-159K7.2 high expression patients was significantly lower than that of RP11-159K7.2 low expression ones (P=0.013 7). After the down-regulation of RP11-159K7.2, the proliferation, migration and invasion ability of SNSCC cells decreased significantly, and the growth of SNSCC xenograft was significantly inhibited. There were 31 candidate proteins that may bind to RP11-159K7.2. RP11-159K7.2 directly bound to nuclear factor-κB (NF-κB) in SNSCC cells, and the regulation of RP11-159K7.2 on the proliferation and invasion of SNSCC cells depended on NF-κB. Conclusion: The increased expression of RP11-159K7.2 in SNSCC may serve as a potential molecular marker for SNSCC prognosis assessment. It is currently considered that the carcinogenic mechanism of RP11-159K7.2 in SNSCC is related to the regulation of NF-κB protein.

Point-of-care Ultrasound-guided Central Venous Catheter Confirmation in Ultrasound Nonexperts

OBJECTIVE

Emerging evidence suggests that chest radiography (CXR) following central venous catheter (CVC) placement is unnecessary when point-of-care ultrasound (POCUS) is used to confirm catheter position and exclude pneumothorax. However, few providers have adopted this practice, and it is unknown what contributing factors may play a role in this lack of adoption, such as ultrasound experience. The objective of this study was to evaluate the diagnostic accuracy of POCUS to confirm CVC position and exclude a pneumothorax after brief education and training of nonexperts.

METHODS

We performed a prospective cohort study in a single academic medical center to determine the diagnostic characteristics of a POCUS-guided CVC confirmation protocol after brief training performed by POCUS nonexperts. POCUS nonexperts (emergency medicine senior residents and critical care fellows) independently performed a POCUS-guided CVC confirmation protocol after a 30-minute didactic training. The primary outcome was the diagnostic accuracy of the POCUS-guided CVC confirmation protocol for malposition and pneumothorax detection. Secondary outcomes were efficiency and feasibility of adequate image acquisition, adjudicated by POCUS experts.

RESULTS

Twenty-six POCUS nonexperts collected data on 190 patients in the final analysis. There were five (2.5%) CVC malpositions and six (3%) pneumothoraxes on CXR. The positive likelihood ratios of POCUS for malposition detection and pneumothorax were 12.33 (95% confidence interval [CI] = 3.26 to 46.69) and 3.41 (95% CI = 0.51 to 22.76), respectively. The accuracy of POCUS for pneumothorax detection compared to CXR was 0.93 (95% CI = 0.88 to 0.96) and the sensitivity was 0.17 (95% CI = 0.00 to 0.64). The median (interquartile range) time for CVC confirmation was lower for POCUS (9 minutes [8.5-9.5 minutes]) compared to CXR (29 minutes [1-269 minutes]; Mann-Whitney U, p < 0.01). Adequate protocol image acquisition was achieved in 76% of the patients.

CONCLUSION

Thirty-minute training of POCUS in nonexperts demonstrates adequate diagnostic accuracy, efficiency, and feasibility of POCUS-guided CVC position confirmation, but not exclusion of pneumothorax.

[Characteristics and Drivers of Dissolved Carbon Dioxide and Methane Concentrations in the Nantiaoxi River System in the Upper Reaches of the Taihu Lake Basin During Summer-Autumn]

Inland waters are vital sinks for active carbon (C) and potential sources of greenhouse gas emissions. In this study, the characteristics of dissolved carbon dioxide (CO₂) and methane (CH₄) concentrations in the Nantiaoxi River system in the upper reaches of the Taihu Lake basin were observed between Jul. 2019 and Nov. 2019 (summer and autumn) using headspace equilibration-gas chromatography. Simultaneously, physical and chemical parameters were also determined to understand the factors influencing dissolved CO₂ and CH₄ concentrations. The results showed that the mean dissolved CO₂ concentrations and saturation levels in water were (505.47±16.99) μg·L^-1 and (256.31±8.32)%, respectively, and the corresponding values for CH₄ were (1.88±0.09) μg·L^-1 and (5218.74±264.30)%, respectively. The saturation levels of dissolved CO₂ and CH₄ at all observation points were greater than 100%, indicating that the Nantiaoxi River system is a potential source of CO₂ and CH₄. The highest mean dissolved CO₂ concentrations in water were found in agricultural areas followed by residential and forest areas, and there were significant differences among the three land-use types. The mean dissolved CH₄ concentrations in the water in residential areas were significantly higher than those in agricultural area forest areas. The dissolved CO₂ concentrations, saturation levels of CO₂, dissolved CH₄ concentrations, and saturation levels of CH₄ in water were all negatively correlated with oxidation reduction potential (ORP) (P<0.01) and positively correlated with electrical conductivity (EC) (P<0.01). The discrepancies in chlorophyll (Chl-a), nitrate (NO₃^--N), total nitrogen (TN), and EC were the main reasons for differences in dissolved CO₂ concentrations among the different land use types. Phytoplankton growth could be promoted by the higher input of nitrogen pollutants into rivers in agricultural and residential areas, and respiration could be also enhanced, resulting in higher dissolved CO₂ concentrations. The higher concentrations of dissolved organic carbon (DOC) and ammonium nitrogen (NH₄⁺-N) in the water, and the water temperature in residential areas, were probably the main causes of the higher dissolved CH₄ concentrations. Rainfall also had some influence on dissolved CO₂ and CH₄ concentrations in the water associated with the different land use types. Specifically, higher concentrations of nitrogen pollutants and the enhancement of DOC were the main drivers of high dissolved CO₂ concentrations in agricultural areas as well as the higher dissolved CH₄ concentrations in residential areas following rainfall events.

microRNA-320b suppresses HNF4G and IGF2BP2 expression to inhibit angiogenesis and tumor growth of lung cancer

We examined the effect of microRNA-320b (miR-320b) on tumor growth and angiogenesis in lung cancer and also determined its downstream molecular mechanisms. Lung cancer tissues and adjacent non-cancerous tissues were collected from 66 patients with lung cancer. miR-320b expression was experimentally determined to be expressed at low level in cancer tissues. The results of gain-of-function experiments suggested that miR-320b overexpression suppressed cancer cell invasion, tube formation, tumor volume and angiogenesis in xenografted nude mice. Hepatocyte nuclear factor 4 gamma (HNF4G) was identified as a target of miR-320b based on in silico analysis. Dual-luciferase reporter gene assays further identified the binding relationship between HNF4G and miR-320b. Lung cancer tissues exhibited increased expression of HNF4G and insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2). Meanwhile, HNF4G knockdown suppressed IGF2BP2 expression, thereby repressing cancer cell invasion and tube formation. Furthermore, IGF2BP2 modified m6A to increase the expression of thymidine kinase 1 (TK1), thus promoting angiogenesis. In nude mice, restoration of TK1 reversed the suppressive effect of miR-320b overexpression on tumor growth rate and CD31 expression. In conclusion, miR-320b suppresses lung cancer growth and angiogenesis by inhibiting HNF4G, IGF2BP2 and TK1.

KDM5A silencing transcriptionally suppresses the FXYD3-PI3K/AKT axis to inhibit angiogenesis in hepatocellular cancer via miR-433 up-regulation

Hepatocellular cancer (HCC) has been reported to belong to one of the highly vascularized solid tumours accompanied with angiogenesis of human umbilical vein endothelial cells (HUVECs). KDM5A, an attractive drug target, plays a critical role in diverse physiological processes. Thus, this study aims to investigate its role in angiogenesis and underlying mechanisms in HCC. ChIP‐qPCR was utilized to validate enrichment of H3K4me3 and KDM5A on the promotor region of miR‐433, while dual luciferase assay was carried out to confirm the targeting relationship between miR‐433 and FXYD3. Scratch assay, transwell assay, Edu assay, pseudo‐tube formation assay and mice with xenografted tumours were conducted to investigate the physiological function of KDM5A‐miR‐433‐FXYD3‐PI3K‐AKT axis in the progression of HCC after loss‐ and gain‐function assays. KDM5A p‐p85 and p‐AKT were highly expressed but miR‐433 was down‐regulated in HCC tissues and cell lines. Depletion of KDM5A led to reduced migrative, invasive and proliferative capacities in HCC cells, including growth and a lowered HUVEC angiogenic capacity in vitro. Furthermore, KDM5A suppressed the expression of miR‐433 by demethylating H3K4me3 on its promoterregion. miR‐433 negatively targeted FXYD3. Depleting miR‐433 or re‐expressing FXYD3 restores the reduced migrative, invasive and proliferative capacities, and lowers the HUVEC angiogenic capacity caused by silencing KDM5A. Therefore, KDM5A silencing significantly suppresses HCC tumorigenesis in vivo, accompanied with down‐regulated miR‐433 and up‐regulated FXYD3‐PI3K‐AKT axis in tumour tissues. Lastly, KDM5A activates the FXYD3‐PI3K‐AKT axis to enhance angiogenesis in HCC by suppressing miR‐433.

Systematic analysis using a bioinformatics strategy identifies SFTA1P and LINC00519 as potential prognostic biomarkers for lung squamous cell carcinoma

Lung cancer has high incidence and mortality rates, in which lung squamous cell carcinoma (LUSC) is a primary type of non-small cell lung carcinoma (NSCLC). The aim of our study was to discover long non-coding RNAs (lncRNAs) associated with diagnose and prognosis for LUSC. RNA sequencing data obtained from LUSC samples were extracted from The Cancer Genome Atlas database (TCGA). Two prognosis-associated lncRNAs (including SFTA1P and LINC00519) were selected from LUSC samples, and the expression levels were also verified to be associated abnormal in LUSC clinical samples. Our findings demonstrate that lncRNAs SFTA1P and LINC00519 exert important functions in human LUSC and may serve as new targets for LUSC diagnosis and therapy.

Comprehensive analysis to identify DLEU2L/TAOK1 axis as a prognostic biomarker in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest malignant tumors that are harmful to human health. Increasing evidence has underscored the critical role of the competitive endogenous RNA (ceRNA) regulatory networks among various human cancers. However, the complexity and behavior characteristics of the ceRNA network in HCC were still unclear. In this study, we aimed to clarify a phosphatase and tensin homolog (PTEN)-related ceRNA regulatory network and identify potential prognostic markers associated with HCC. The expression profiles of three RNAs (long non-coding RNAs [lncRNAs], microRNAs [miRNAs], and mRNAs) were extracted from The Cancer Genome Atlas (TCGA) database. The DLEU2L-hsa-miR-100-5p/ hsa-miR-99a-5p-TAOK1 ceRNA network related to the prognosis of HCC was obtained by performing bioinformatics analysis. Importantly, we identified the DLEU2L/TAOK1 axis in the ceRNA by using correlation analysis, and it appeared to become a clinical prognostic model by Cox regression analysis. Furthermore, methylation analyses suggested that the abnormal upregulation of the DLEU2L/TAOK1 axis likely resulted from hypomethylation, and immune infiltration analysis showed that the DLEU2L/TAOK1 axis may have an impact on the changes in the tumor immune microenvironment and the development of HCC. In summary, the current study constructing a ceRNA-based DLEU2L/TAOK1 axis might be a novel important prognostic factor associated with the diagnosis and prognosis of HCC.

[Application of rigid curved laryngoscope in the examination of hypopharynx and the treatment of early hypopharyngeal cancer]

Objective: To evaluate the efficacy of curved suspension laryngoscope assistant transoral surgery (CLATOS) in the examination of hypopharynx, and diagnosis and surgery of early hypopharyngeal carcinoma. Methods: Thirty-four patients who underwent detailed examination for lower part of hypopharynx and surgery for early hypopharyngeal carcinoma with CLATOS technique in the Second Affiliated Hospital of Harbin Medical University from January 2019 to January 2020 were analyzed retrospectively. The age ranged from 42 to 74 years old including 28 males and 6 females. Among them, 25 patients complaining of foreign body sensation in the pharynx for more than half a year with a poor exposure of the lower pharynx in the examination with flexible laryngoscope in the outpatient department were admitted to the hospital for the further examination with rigid curved laryngoscopy and 9 patients with stage T1-2 hypopharyngeal squamous cell carcinoma were operated with CLATOS technique. Preoperative, intraoperative and postoperative data were analized. Results: One case of squamous cell carcinoma in esophageal entrance (T1N0M0) and one case of carcinoma in pyriform sinus (T1N0M0) with cervical esophageal carcinoma (T1N0M0) were found in the 25 patients with foreign body sensation in the pharynx. En bloc resection of cancer was obtained in 9 patients with stage T1-2 hypopharyngeal carcinomas and 2 of them underwent tracheotomy. One patient with T1 retrocricoid carcinoma was found to have a carcinoma in situ at the lower part of posterior hypopharyngeal wall in the examination during follow-up, which was resected simultaneously. Postoperatively this patient developed a stenosis in the esophageal entrance, which was dilated twice until swallowing normally. Two patients of T2N0M0 and one of T2N1M0 underwent bilateral neck lymph node dissection just after the removal of primary tumors. During follow-up, none of the 9 patients showed tumor recurrence and complications such as dysphonia and dyspnea. Conclusion: CLATOS technique can provide a promising way in the examination of hypopharynx and the detection of early lesions of hypopharynx and esophageal entrance, and this technique has also the advantages such as full visual angle and easy operation for the resection of early hypopharyngeal carcinoma. The quality of life of patients can be improved while the tumor is removed en bloc with this technique.

Long Noncoding RNA OIP5-AS1 Promotes the Progression of Liver Hepatocellular Carcinoma via Regulating the hsa-miR-26a-3p/EPHA2 Axis

Numerous studies have suggested that dysregulated long noncoding RNAs (lncRNAs) contributed to the development and progression of many cancers. lncRNA OIP5 antisense RNA 1 (OIP5-AS1) has been reported to be increased in several cancers. However, the roles of OIP5-AS1 in liver hepatocellular carcinoma (LIHC) remain to be investigated. In this study, we demonstrated that OIP5-AS1 was upregulated in LIHC tissue specimens and its overexpression was associated with the poor survival of patients with LIHC. Furthermore, loss-of function experiments indicated that OIP5-AS1 promoted cell proliferation and inhibited cell apoptosis both in vitro and in vivo. Moreover, binding sites between OIP5-AS1 and hsa-miR-26a-3p as well as between hsa-miR-26a-3p and EPHA2 were confirmed by luciferase assays. Finally, a rescue assay was performed to prove the effect of the OIP5-AS1/hsa-miR-26a-3p/EPHA2 axis on LIHC cell biological behaviors. Based on all of the above findings, our results suggested that OIP5-AS1 promoted LIHC cell proliferation and invasion via regulating the hsa-miR-26a-3p/EPHA2 axis.

[48,XXYY syndrome: A report of four cases]

OBJECTIVE

To explore the clinical characteristics and prognosis of the 48,XXYY syndrome and gain a deeper insight into this condition.

METHODS

This retrospective study included 4 cases of 48,XXYY syndrome confirmed between 2011 and 2018. We analyzed the general information, clinical manifestations, laboratory results, imaging features and outcomes of assisted reproductive technology (ART) of the patients and reviewed the relevant literature.

RESULTS

The 4 patients with 48,XXYY syndrome were characterized by low literacy, soft texture and small volume of the testis, high levels of FSH and LH, and low level of serum T. Two of them were diagnosed with ejaculatory dysfunction and aspermia, and the other 2 with normal ejaculatory function but azoospermia. Biochemical analysis of seminal plasma indicated normal quantifications of both fructose and neutral α glucosidase. ART with donor sperm was performed for all the 4 cases and 3 of them got full-term babies.

CONCLUSIONS

The 48,XXYY syndrome is often complicated by hypergonadotropic hypogonadism, with the clinical manifestations of aspermia or non-obstructive azoospermia. ART with donor sperm can be employed to help the patient with 48,XXYY syndrome get their non-biological offspring.

[Indirect Nitrous Oxide Emissions from an Agricultural Headwater Stream During the Rainy Season in the Upper Reach of the Yangtze River]

Agricultural headwater streams have a close hydrologic connection with adjacent farmland ecosystems. Based on the aggravation of agricultural nonpoint source of nitrogen (N) pollution, these streams can become an important sink of N and source of indirect nitrous oxide (N₂O) emission. In this study, indirect N₂O emissions from an agricultural headwater stream in the hilly area of purple soil in the upper reach of the Yangtze River were measured in situ using the closed static chamber-GC technique during the rainy season (June to September 2015). The results show that the headwater stream is a source of indirect N₂O emissions, with a mean emission rate of 12.8 μg·(m²·h)^-1, which is close to the direct N₂O emission level from local farmland during the same season. The indirect N₂O emission factor (EF_5r=0.01%) determined in this study is much lower than the default value proposed by the Intergovernmental Panel on Climate Change (0.25%; IPCC, 2006) for the estimation of indirect agricultural N₂O emissions and far lower than the recalculated mean value (0.20%) based on available global data. However, based on the limited number of studies on EF_5r and the high spatial variations among them, more in situ observations are needed and vital to generate more accurate EF_5r values and reduce the uncertainty of indirect N₂O estimations calculated based on the EF_5r. The indirect N₂O fluxes are positively correlated with the NO₃^--N concentrations of the stream. Thus, denitrification is the main process of N₂O production. Moreover, the indirect N₂O fluxes could be notably promoted by the rapid increase of the NO₃^--N concentrations that were driven by rainfall>9 mm during days with continuous rain.

[Comprehensive analysis of the effect of null zone shifting surgery treatment on patients with infantile nystagmus syndrome]

Objective: To characterize the postoperative change of eyes related parameters of patients with infantile nystagmus syndrome(INS), so as to provide a reference for the clinical evaluation of postoperative effect and the rational arrangement of patients' follow-up time after operation. Methods: A retrospective study. Clinical and follow-up data of 17 patients diagnosed with INS at Department of Ophthalmology in Xinhua Hospital, School of Medicine, Shanghai Jiaotong University from June 2014 to December 2016 were collected. All patients with abnormal head posture (AHP) underwent null zone shift surgery. The operative methods were Parks 5-6-7-8, Anderson, Kestenbum 5-5-6-4,null zone shift combined with strabismus correction and vertical null zone transposition. Ophthalmological examination and eye movement were recorded, including best corrected binocular visual acuity (BCBVA), position of the null zone, expanded nystagmus acuity function (NAFX) and foveation time. Single factor repeated analysis of variance, independent sample t test and rank sum test were used for statistical analysis. Results: Among the 17 children, 6 were females and 11 were males. The age at surgery of the patients was 5-11 years.The follow-up time was (14.8±6.0) months. Preoperative BCBVA was 0.382±0.147 (corrected posture), 0.300±0.056 (AHP); foveation time was (0.594±0.011)s;position of null zone was 23.570°±0.118°. The BCBVA at three months after operation was 0.318±0.044 (corrected posture), 0.260±0.045 (AHP); foveation time was (0.950±0.146)s; position of null zone was 5.360°±1.107°. The BCBVA at six months after operation was 0.264±0.039 (corrected posture), 0.230±0.037 (AHP);foveation time was (1.496±0.233) s; position of null zone was 6.070°±1.303°. The BCBVA at twelve months after operation was 0.309±0.039 (corrected posture), 0.250±0.045 (AHP);foveation time was (1.455±0.201) s; position of null zone was 9.290°±8.520°. There was statistical difference between the data of pre-operation and post-operation(all P<0.05). Change of null zone position was identified in six patients after six months.The preoperative NAFX of patients with presence of change of null zone positon was 0.308±0.063 (the primary position), 0.393±0.210 (null zone); BCBVA was 0.450±0.043 (corrected posture), 0.417±0.031 (AHP); foveation time was 0.122 (0.080-1.014)s. The postoperative NAFX of those patients was 0.430±0.090(the primary position), 0.471±0.140 (null zone); foveation time was 0.438(0.170-1.450) s. The data above were lower than that of patients with no regression of null zone[0.523±0.142,0.601±0.110,0.200±0.063,0.250±0.076,0.725(0.230-1.440)s,0.610±0.160,0.680±0.120,0.975(0.380-2.000)s]. The difference was statistically significant(all P<0.05). Conclusions: Null zone shifting surgery is an effective approach for treating INS. Reduction in the null zone position can be observed in some patients at 6 months after operation, which was related to NAFX, BCBVA and foveation time. It is recommended to extend the follow-up time to at least 6 months after the operation. (Chin J Ophthalmol, 2019, 55:13-19).

[Nitrous Oxide Emissions and Its Influencing Factors from an Agricultural Headwater Ditch During a Maize Season in the Hilly Area of Central Sichuan Basin]

Agricultural headwater ditches, the important locations for retaining and transforming nitrogen derived from the adjacent farmlands, have been regarded as the potential source of nitrous oxide (N₂O) emission. In this study, N₂O emissions from a typical agricultural ditch in the Hilly Area of Central Sichuan Basin, were observed by closed static chamber-GC technique during the maize season (rainy season), from June to the end of September. During the study period, cumulative N₂O emissions in the sediment-water interface without vegetation (NV) and the ditch ecosystem with natural vegetation (V) were 0.07 and 0.43 kg·hm^-2, respectively. Meanwhile, the mean N₂O flux from the agricultural headwater ditch ecosystem[14.7 μg·(m²·h)^-1] was comparable to the magnitude of direct N₂O flux from the maize cropland in this region. Nitrate concentration in the overlying water could be the main factor governing N₂O emission from the ditch, especially in the rainy season. The existence of vegetation increased the indirect N₂O emission factor (V:0.05% vs.NV:0.01%). The indirect N₂O emission factor from this field investigation was much lower than the default value proposed by the Intergovernmental Panel on Climate Change (IPCC, 2006) for assessing indirect agricultural N₂O emissions. More attention should be paid to in situ measurements to reduce uncertainty of N₂O estimation calculated by only applying the default value for emission factor from the IPCC.

[Seasonal Variation in Nitric Oxide Emission from an Agricultural Headwater Ditch in the Hilly Purple Soil Area and the Factors Influencing Emission]

Agricultural headwater ditches are important pathways of reactive nitrogen loss from adjacent croplands, and also act as hotspots for reactive nitrogen transformation. In this study, NO emissions from a typical agricultural ditch in the hilly area of central Sichuan Basin were measured by the closed static chamber-chemiluminescence method, from December 2014 to November 2015. The results showed that the cumulative NO emissions from the sediment-water interface without vegetation (NV) and the ditch ecosystem with natural vegetation (Ⅴ) were -0.4 g·(hm²·a)^-1 and 14.17 g·(hm²·a)^-1, respectively. The combined annual NO emission flux for the agricultural headwater ditch ecosystem was 11.27 g·(hm²·a)^-1, with a mean NO emission rate of 0.13 μg·(m²·h)^-1. A net source of NO from the ditch ecosystem only occurred in summer, which had a significantly higher cumulative NO emission than those in the other seasons. The seasonal variation in NO emissions was mainly regulated by the seasonal changes in NO₃^--N concentrations and temperature in the overlying water. Meanwhile, the presence of vegetation in the ditch ecosystem significantly increased NO emission rates, whereas it did not markedly influence the annual NO emission.

[The first confirmed imported case of yellow fever in China]

OBJECTIVE

To describe the epidemiological characteristics of the first confirmed imported case of yellow fever in China.

METHODS

This case was reported through the Infectious Disease Surveillance Program. Information on epidemiology and clinical manifestation of the case was collected through case interview and related medical records. Blood and saliva samples of the case were collected and tested by real-time PCR.

RESULTS

The patient was male, 32 years old, and suffered a sudden onset of fever without other symptoms, on March 8(th), 2016. The patient arrived in Beijing at midnight on March 10(th). Condition of the patient got progressively worsened, with both liver and renal failures, hepatic encephalopathy, multiple organ failures and DIC, finally died on March 16(th). Serum of the case was positive for yellow fever virus by real time PCR. The patient was bit by mosquitoes six days before the onset of fever in Luanda, Angola.

CONCLUSION

This report summarized related information on the first confirmed but imported case of yellow fever in China that was helpful to the management of other imported yellow fever cases in the future.

[Establishment of Automation System for Detection of Alcohol in Blood]

OBJECTIVES

To establish an automation system for detection of alcohol content in blood.

METHODS

The determination was performed by automated workstation of extraction-headspace gas chromatography （HS-GC）. The blood collection with negative pressure, sealing time of headspace bottle and sample needle were checked and optimized in the abstraction of automation system. The automatic sampling was compared with the manual sampling.

RESULTS

The quantitative data obtained by the automated workstation of extraction-HS-GC for alcohol was stable. The relative differences of two parallel samples were less than 5%. The automated extraction was superior to the manual extraction. A good linear relationship was obtained at the alcohol concentration range of 0.1-3.0 mg/mL （r≥0.999） with good repeatability.

CONCLUSIONS

The method is simple and quick, with more standard experiment process and accurate experimental data. It eliminates the error from the experimenter and has good repeatability, which can be applied to the qualitative and quantitative detections of alcohol in blood.

Neuroimaging Analysis of the Dopamine Basis for Apathetic Behaviors in an MPTP-Lesioned Primate Model

Apathy commonly occurs in Parkinson disease (PD) patients; however, the role of dopamine in the pathophysiology of apathy remains elusive. We previously demonstrated that dopaminergic dysfunction within the ventral tegmental area (VTA)-nucleus accumbens (NAcc) pathway contributes to the manifestation of apathetic behaviors in monkeys treated with the selective dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We now extend these studies to identify dopaminergic dysfunction in cortical regions that correlate with development of apathetic behaviors. Specifically, we measured the effects of MPTP on monkeys' willingness to attempt goal directed behaviors, which is distinct from their ability to perform tasks. A total of 16 monkeys had baseline magnetic resonance imaging (MRI) and positron emission tomography (PET), using 6-[¹⁸F]fluorodopa (FD), [¹¹C]dihydrotetrabenazine (DTBZ), and 2β-[¹¹C]carbomethoxy-3β-(4-fluorophenyl)tropane (CFT). The monkeys received unilateral infusion of different doses of MPTP (0 – 0.31mg/kg) to produce a wide range of severity of motor parkinsonism. Eight weeks after MPTP, PET scans were repeated and animals were euthanized. Apathetic behavior and motor impairments were assessed blindly both pre- and post-MPTP infusion. Apathy scores were compared to in vitro and in vivo dopaminergic measures. Apathy scores increased following MPTP and correlated with PET measures of dopaminergic terminals (DTBZ or CFT) in dorsal lateral prefrontal cortex (DLPFC), ventromedial prefrontal cortex (VMPFC), and insular cortex (IC). Among all the cortical regions assessed, forward step-wise regression analyses indicated that only stereologic cell counts in VTA, and not counts in the substantia nigra (SN), predict dopamine transporter changes in IC. Our findings suggest that dopaminergic dysfunction within the VTA–IC pathway plays a role in the manifestation of apathetic behaviors in MPTP-lesioned primates.

Carboxyfullerene neuroprotection postinjury in Parkinsonian nonhuman primates

OBJECTIVE

We evaluated the efficacy of the potent antioxidant C3 to salvage nigrostriatal neuronal function after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) exposure in nonhuman primates. C3 is a first-in-class functionalized water-soluble fullerene that reduces oxygen radical species associated with neurodegeneration in in vitro studies. However, C3 has not been evaluated as a neuroprotective agent in a Parkinson model in vivo.

METHODS

Macaque fascicularis monkeys were used in a double-blind, placebo-controlled study design. MPTP-lesioned primates were given systemic C3 (n = 8) or placebo (n = 7) for 2 months starting 1 week after MPTP. Outcomes included in vivo behavioral measures of motor parkinsonism using a validated nonhuman primate rating scale, kinematic analyses of peak upper extremity velocity, positron emission tomography imaging of 6-[(18) F]fluorodopa (FD; reflects dopa decarboxylase) and [(11) C]dihydrotetrabenazine (DTBZ; reflects vesicular monoamine transporter type 2), ex vivo quantification of striatal dopamine, and stereologic counts of tyrosine hydroxylase-immunostained neurons in substantia nigra.

RESULTS

After 2 months, C3 -treated monkeys had significantly improved parkinsonian motor ratings, greater striatal FD and DTBZ uptake, and higher striatal dopamine levels. None of the C3 -treated animals developed any toxicity.

INTERPRETATION

Systemic treatment with C3 reduced striatal injury and improved motor function despite administration after the MPTP injury process had begun. These data strongly support further development of C3 as a promising therapeutic agent for Parkinson disease.

In vivo measures of nigrostriatal neuronal response to unilateral MPTP treatment

A single unilateral intracarotid infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into non-human primates causes injury to the nigrostriatal pathway including nigral cell bodies, axons and striatal terminal fields. In this model, motor parkinsonism correlates well with the loss of nigral dopaminergic cell bodies but only correlates with in vitro measures of nigrostriatal terminal fields when nigral cell loss does not exceed 50%. The goals of this study are to determine the relationship of motor parkinsonism with the degree of injury to nigrostriatal axons, as reflected by in vitro fiber length density measures, and compare in vivo with in vitro measures of striatal terminal fields. We determined axon integrity by measuring fiber length density with tyrosine hydroxylase (TH) immunohistology and dopamine transporter (DAT) density with DAT immunohistology. We then calculated the terminal arbor size and compared these measures with previously published data of quantified in vivo positron emission tomography (PET) measures of presynaptic dopaminergic neurons, autoradiographic measures of DAT and vesicular monoamine transporter type 2 (VMAT2), striatal dopamine, nigral cell counts, and parkinsonian motor ratings in the same animals. Our data demonstrate that in vivo and in vitro measures of striatal terminal fields correlate with each other regardless of the method of measurement. PET-based in vivo striatal measures accurately reflect in vitro measures of DAT and VMAT2. Terminal arbor size and other terminal field measures correlate with nigral TH immunoreactive (TH-ir) cell counts only when nigral TH-ir cell loss does not exceed 50%. Fiber length density was the only striatal measure that linearly correlated with motor ratings (Spearman: r=-0.81, p<0.001, n=16).

Validation of midbrain positron emission tomography measures for nigrostriatal neurons in macaques

OBJECTIVE

Development of an effective therapy to slow the inexorable progression of Parkinson disease requires a reliable, objective measurement of disease severity. In the present study, we compare presynaptic positron emission tomography (PET) tracer uptake in the substantia nigra (SN) to cell loss and motor impairment in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated nonhuman primates.

METHODS

Presynaptic PET tracers 6-[(18)F]-fluorodopa (FD), [(11)C]-2β-methoxy-3β-4-fluorophenyltropane (CFT), and [(11)C]-dihydrotetrabenazine (DTBZ) were used to measure specific uptake in the SN and striatum before and after a variable dose of MPTP in nonhuman primates. These in vivo PET-based measures were compared with motor impairment, as well as postmortem tyrosine hydroxylase-positive cell counts and striatal dopamine concentration.

RESULTS

We found the specific uptake of both CFT and DTBZ in the SN had a strong, significant correlation with dopaminergic cell counts in the SN (R(2) = 0.77, 0.53, respectively, p < 0.001), but uptake of FD did not. Additionally, both CFT and DTBZ specific uptake in the SN had a linear relationship with motor impairment (rs = -0.77, -0.71, respectively, p < 0.001), but FD uptake did not.

INTERPRETATION

Our findings demonstrate that PET-measured binding potentials for CFT and DTBZ for a midbrain volume of interest targeted at the SN provide faithful correlates of nigral neuronal counts across a full range of lesion severity. Because these measures correlate with both nigral cell counts and parkinsonian ratings, we suggest that these SN PET measures are relevant biomarkers of nigrostriatal function.

Validation of nigrostriatal positron emission tomography measures: critical limits

OBJECTIVE

Molecular imaging and clinical endpoints are frequently discordant in Parkinson disease clinical trials, raising questions about validity of these imaging measures to reflect disease severity. We compared striatal uptake for 3 positron emission tomography (PET) tracers with in vitro measures of nigral cell counts and striatal dopamine in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys.

METHODS

Sixteen macaques had magnetic resonance imaging and baseline PETs using 6-[18F]fluorodopa (FD), [11C]dihydrotetrabenazine (DTBZ), and 2beta-[11 C]carbomethoxy-3beta-(4-fluorophenyl)tropane (CFT). MPTP (0-0.31 mg/kg) infused unilaterally via the internal carotid artery produced stable hemiparkinsonism by 3 weeks. After 8 weeks, PETs were repeated and animals were euthanized for striatal dopamine measurements and unbiased counts of tyrosine hydroxylase-stained nigral cells.

RESULTS

Striatal uptake for each radiotracer (FD, DTBZ, CFT) correlated with stereologic nigral cell counts only for nigral loss<50% (r2=0.84, r2=0.86, r2=0.87, p<0.001 respectively; n=10). In contrast, striatal uptake correlated with striatal dopamine over the full range of dopamine depletion (r2=0.95, r2=0.94, r2=0.94, p<0.001; n=16). Interestingly, indices of striatal uptake of FD, DTBZ, and CFT correlated strongly with each other (r2=0.98, p<0.001).

INTERPRETATION

Tracer uptake correlated with nigral neurons only when nigral loss was <50%. This along with previous work demonstrating that nigral cell counts correlate strongly with parkinsonism ratings may explain discordant results between neuroimaging and clinical endpoints. Furthermore, strong correlations among striatal uptake for these tracers support lack of differential regulation of decarboxylase activity (FD), vesicular monoamine transporter type 2 (DTBZ), and dopamine transporter (CFT) within 2 months after nigrostriatal injury.

Dopamine pathway loss in nucleus accumbens and ventral tegmental area predicts apathetic behavior in MPTP-lesioned monkeys

Apathy, primarily defined as a lack of motivation, commonly occurs in people with Parkinson disease (PD). Although dysfunction of basal ganglia pathways may contribute to apathy, the role of dopamine remains largely unknown. We investigated the role of dopaminergic pathways in the manifestation of apathetic behaviors by measuring the effects of the selective dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on monkeys' willingness to attempt goal directed behaviors, distinct from their ability to perform tasks. Fifteen macaques received variable doses of MPTP, had PET scans with [(11)C]-dihydrotetrabenazine (DTBZ), [(11)C]-2β-3β-4-fluorophenyltropane (CFT), and [(18)F]-fluorodopa (FD) and performed tasks to assess apathetic behaviors and motor impairment. At 8 weeks post-MPTP, primates were euthanized and stereological cell counts and dopamine measurements were done. Apathy scores were compared to motor scores, in vitro and in vivo dopaminergic measures. Apathy scores increased following MPTP and correlated with DTBZ (r(S) = -0.85), CFT (r(S) = -0.87), and FD (r(S) = -0.85) specific uptake in nucleus accumbens (NAcc,) and dopaminergic cell counts in ventral tegmental area (VTA, r(S) = -0.80). Dopaminergic cell loss in VTA provided significant predictive power for apathy scores after controlling for the influence of cell loss in SN. Additionally, forward step-wise regression analyses indicated that neuropathological changes in the VTA-NAcc pathway predict apathetic behavior better than motor impairment or neuropathological changes in the nigrostriatal network. Our findings suggest that dopaminergic dysfunction within the VTA-NAcc pathway plays a role in the manifestation of apathetic behaviors in MPTP-lesioned primates. Similar changes in people with PD may contribute to apathy.

No differential regulation of dopamine transporter (DAT) and vesicular monoamine transporter 2 (VMAT2) binding in a primate model of Parkinson disease

Radioligands for DAT and VMAT2 are widely used presynaptic markers for assessing dopamine (DA) nerve terminals in Parkinson disease (PD). Previous in vivo imaging and postmortem studies suggest that these transporter sites may be regulated as the numbers of nigrostriatal neurons change in pathologic conditions. To investigate this issue, we used in vitro quantitative autoradioradiography to measure striatal DAT and VMAT2 specific binding in postmortem brain from 14 monkeys after unilateral internal carotid artery infusion of 1-Methyl-4-Phenyl-1,2,3,6-tetrahydropyridine (MPTP) with doses varying from 0 to 0.31 mg/kg. Quantitative estimates of the number of tyrosine hydroxylase (TH)-immunoreactive (ir) neurons in substantia nigra (SN) were determined with unbiased stereology, and quantitative autoradiography was used to measure DAT and VMAT2 striatal specific binding. Striatal VMAT2 and DAT binding correlated with striatal DA (r_s = 0.83, r_s = 0.80, respectively, both with n = 14, p<0.001) but only with nigra TH-ir cells when nigral cell loss was 50% or less (r = 0.93, n = 8, p = 0.001 and r = 0.91, n = 8, p = 0.002 respectively). Reduction of VMAT2 and DAT striatal specific binding sites strongly correlated with each other (r = 0.93, n = 14, p<0.0005). These similar changes in DAT and VMAT2 binding sites in the striatal terminal fields of the surviving nigrostriatal neurons demonstrate that there is no differential regulation of these two sites at 2 months after MPTP infusion.

Salvianolic acid B, an antioxidant from Salvia miltiorrhiza, prevents 6-hydroxydopamine induced apoptosis in SH-SY5Y cells

Oxidative stress caused by dopamine may play an important role in the pathogenesis of Parkinson's disease. Salvianolic acid B is an antioxidant derived from the Chinese herb, Salvia miltiorrhiza. In this study, we investigated the neuroprotective effect of salvianolic acid B against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells. Pretreatment of SH-SY5Y cells with salvianolic acid B significantly reduced 6-hydroxydopamine-induced generation of reactive oxygen species, and prevented 6-hydroxydopamine-induced increases in intracellular calcium. Our data demonstrated that 6-hydroxydopamine-induced apoptosis was reversed by salvianolic acid B treatment. Salvianolic acid B reduced the 6-hydroxydopamine-induced increase of caspase-3 activity, and reduced cytochrome C translocation into the cytosol from mitochondria. The 6-hydroxydopamine-induced decrease in the Bcl-x/Bax ratio was prevented by salvianolic acid B. Additionally, salvianolic acid B decreased the activation of extracellular signal-regulated kinase and induced the activation of 6-hydroxydopamine-suppressed protein kinase C. These results indicate that the protective function of salvianolic acid B is dependent upon its antioxidative potential. Our results strongly suggest that salvianolic acid B may be effective in treating neurodegenerative diseases associated with oxidative stress.

Protective effect of (+/-) isoborneol against 6-OHDA-induced apoptosis in SH-SY5Y cells

Oxidative stress caused by dopamine (DA) may play an important role in the pathogenesis of Parkinson's disease (PD). (+/-) Isoborneol is a monoterpenoid alcohol present in the essential oils of numerous medicinal plants and is a known antioxidant. In this study, we investigated the neuroprotective effect of isoborneol against 6-hydroxydopamine (6-OHDA)-induced cell death in human neuroblastoma SH-SY5Y cells. Pretreatment of SH-SY5Y cells with isoborneol significantly reduced 6-OHDA-induced generation of reactive oxygen species (ROS) and 6-OHDA-induced increases in intracellular calcium. Furthermore, apoptosis induced by 6-OHDA was reversed by isoborneol treatment. Isoborneol protected against 6-OHDA-induced increases in caspase-3 activity and cytochrome C translocation into the cytosol from mitochondria. Isoborneol prevented 6-OHDA from decreasing the Bax/Bcl-2 ratio. We also observed that isoborneol decreased the activation of c-Jun N-terminal kinase and induced activation of protein kinase C (PKC) which had been suppressed by 6-OHDA. Our results indicate that the protective function of isoborneol is dependent upon its antioxidant potential and strongly suggest that isoborneol may be an effective treatment for neurodegenerative diseases associated with oxidative stress.