Calretinin-Expressing Synapses Show Improved Synaptic Efficacy with Reduced Asynchronous Release during High-Rate Activity.

Calretinin (CR) is a major calcium binding protein widely expressed in the CNS. However, its synaptic function remains largely elusive. At the auditory synapse of the endbulb of Held, CR is selectively expressed in different subtypes. Combining electrophysiology with immunohistochemistry, we investigated the synaptic transmission at the endbulb of Held synapses with and without endogenous CR expression in mature CBA/CAJ mice of either sex. Two synapse subtypes showed similar basal synaptic transmission, except a larger quantal size in CR-expressing synapses. During high-rate stimulus trains, CR-expressing synapses showed improved synaptic efficacy with significantly less depression and lower asynchronous release, suggesting more efficient exocytosis than non-CR-expressing synapses. Conversely, CR-expressing synapses had a smaller readily releasable pool size, which was countered by higher release probability and faster synaptic recovery to support sustained release during high-rate activity. EGTA-AM treatment did not change the synaptic transmission of CR-expressing synapses, but reduced synaptic depression and decreased asynchronous release at non-CR-expressing synapses, suggesting that CR helps to minimize calcium accumulation during high-rate activity. Both synapses express parvalbumin, another calcium-binding protein with slower kinetics and higher affinity than CR, but not calbindin. Furthermore, CR-expressing synapses only express the fast isoform of vesicular glutamate transporter 1 (VGluT1), while most non-CR-expressing synapses express both VGluT1 and the slower VGluT2, which may underlie their lagged synaptic recovery. The findings suggest that, paired with associated synaptic machinery, differential CR expression regulates synaptic efficacy among different subtypes of auditory nerve synapses to accomplish distinctive physiological functions in transmitting auditory information at high rates.SIGNIFICANCE STATEMENT CR is a major calcium-binding protein in the brain. It remains unclear how endogenous CR impacts synaptic transmission. We investigated the question at the large endbulb of Held synapses with selective CR expression and found that CR-expressing and non-CR-expressing synapses had similar release properties under basal synaptic transmission. During high-rate activity, however, CR-expressing synapses showed improved synaptic efficacy with less depression, lower asynchronous release, and faster recovery. Furthermore, CR-expressing synapses use exclusive VGluT1 to refill synaptic vesicles, while non-CR-expressing synapses use both VGluT1 and the slower isoform of VGluT2. Our findings suggest that CR may play significant roles in promoting synaptic efficacy during high-rate activity, and selective CR expression can differentially impact signal processing among different synapses.

Biased auditory nerve central synaptopathy is associated with age-related hearing loss.

KEY POINTS: Sound information is transmitted by different subtypes of spiral ganglion neurons (SGN) from the ear to the brain. Selective damage of SGN peripheral synapses (cochlear synaptopathy) is widely recognized as one of the primary mechanisms of hearing loss, whereas the mechanisms at the SGN central synapses remain unclear. We report that different subtypes of SGN central synapses converge at different ratios onto individual target cochlear nucleus neurons with distinct physiological properties, and show biased morphological and physiological changes during age-related hearing loss (ARHL). The results reveal a new dimension in cochlear nucleus neural circuitry that systematically reassembles and processes auditory information from different SGN subtypes, which is altered during ageing and probably contributes to the development of ARHL. In addition to known cochlear synaptopathy, the present study shows that SGN central synapses are also pathologically changed during ageing, which collectively helps us better understand the structure and function of SGNs during ARHL. ABSTRACT: Sound information is transmitted from the cochlea to the brain by different subtypes of spiral ganglion neurons (SGN), which show varying degrees of vulnerability under pathological conditions. Selective cochlear synaptopathy, the preferential damage of certain subtypes of SGN peripheral synapses, has been recognized as one of the main mechanisms of hearing loss. The organization and function of the auditory nerve (AN) central synapses from different subtypes of SGNs remain unclear, including how different AN synapses reassemble onto individual neurons in the cochlear nucleus, as well as how they differentially change during hearing loss. Combining immunohistochemistry with electrophysiology, we investigated the convergence pattern and subtype-specific synaptopathy of AN synapses at the endbulb of Held, as well as the response properties of their postsynaptic bushy neurons in CBA/CaJ mice of either sex under normal hearing and age-related hearing loss (ARHL). We found that calretinin-expressing (type Ia ) and non-calretinin-expressing (type Ib /Ic ) endbulbs converged along a continuum of different ratios onto individual bushy neurons with varying physiological properties. Endbulbs degenerated during ageing in parallel with ARHL. Furthermore, the degeneration was more severe in non-calretinin-expressing synapses, which correlated with a gradual decrease in bushy neuron subpopulation predominantly innervated by these inputs. These synaptic and cellular changes were profound in middle-aged mice when their hearing thresholds were still relatively normal and prior to severe ARHL. Our findings suggest that biased AN central synaptopathy and the correlated shift in cochlear nucleus neuronal composition play significant roles in weakened auditory input and altered central auditory processing during ARHL.

Enhanced expression of lncRNA ZXF1 promotes cisplatin resistance in lung cancer cell via MAPK axis.

Long non-coding RNA (lncRNA) ZXF1 has recently been associated with the poor prognosis of lung cancer by promoting metastasis. However, little is known regarding the role of ZXF1 in lung cancer treatment and the underlying mechanism. Here, using lung cancer tissue and chemoresistant lung cancer cells, we investigated the interaction of ZXF1 with the efficacy of cisplatin, the first-line chemotherapy for lung cancer. We found that ZXF1 overexpression in lung cancer tissue increased the risk of treatment failure and tumor recurrence. We also provided evidence that ZXF1 contributed to cisplatin resistance and cancer progression via activating ERK, JNK and p38-mediated MAPK signaling cascade. In contrast, deactivating MAPK pathway by ZXF1 silencing enhanced cisplatin-induced cell cycle arrest and apoptosis by activating p53/p21 axis. Moreover, ZXF1 knockdown suppressed MAPK-regulated expression of MMP-2 and MMP-9, the enzymes responsible for degrading extracellular matrix, and thus decreased the invasion and migration capability of the cells. All these changes inhibited rapid cell proliferation and restored cellular sensitivity to cisplatin treatment. Taken together, our study revealed that lncRNA ZXF1 contributes to cisplatin resistance and leads to the poor prognosis of lung cancer via activating MAPK pathway, which represents as a promising target to optimize lung cancer treatment.

Long Non-Coding RNA Brain Cytoplasmic RNA 1 Acts as an Oncogene and Regulates Cell Proliferation and Metastasis in Non-Small Cell Lung Cancer.

Long non-coding RNAs (lncRNAs) can serve as oncogenes and tumor suppressors and are involved in tumorigenesis and chemotherapy resistance. Brain cytoplasmic RNA 1 (BCYRN1), as a translational modulator, is an lncRNA comprised of 200 bases that plays an important role in multiple cancers. In this study, we explored the biological role of the lncRNA, BCYRN1, in the development of non-small cell lung cancer (NSCLC). We found that BCYRN1 was increased in NSCLC, and its downregulated expression could suppress NSCLC cell proliferation and cell cycle progression by inhibiting the Wnt/ß-catenin pathway. Our results showed that the expression of BCYRN1 was higher in lung cancer cells compared with a normal bronchial epithelial cell line. Moreover, downregulation of BCYRN1 expression could inhibit cell proliferation and migration and induce apoptosis. Knockdown of BCYRN1 in NSCLC cells reduced a cohort of molecules (ß-catenin, c-Myc and cyclin D1) which are critical for cell proliferation and apoptosis. Our results suggested that BCYRN1 induces the proliferation and migration of NSCLC cells and plays an important role in NSCLC progression. BCYRN1 may provide a new target for therapeutic intervention in NSCLC.

Serum lipid and lipoprotein levels of middle-aged and elderly Chinese men and women in Shandong Province.

BACKGROUND: Cardiovascular and cerebrovascular diseases have become leading causes of death in China as the economy develop and lifestyles change. This study aimed to estimate the relationship of the age, gender, and glucose metabolism with the serum lipid and lipoprotein levels of middle-aged and elderly Chinese men and women in Shandong Province. METHODS: We conducted a cross-sectional study in Shandong Province that included 10,028 adults aged ≥40 years. Fasting serum total, low-density lipoprotein (LDL), high-density lipoprotein (HDL) cholesterol and triglycerides were measured by standard methods. RESULTS: The estimates of total, LDL, and HDL cholesterol and triglycerides were as follows: 5.35, 3.18, 1.51, and 1.34 mmol/L in the middle-aged and elderly Chinese adult population; 5.14, 3.08, 1.42, and 1.33 mmol/L in male subjects; 5.46, 3.24, 1.56, and 1.34 mmol/L in females; 5.27, 3.11, 1.54, and 1.24 mmol/L in the normal glucose tolerance population, 5.49, 3.27, 1.50, and 1.41 mmol/L in the population with pre-diabetes, and 5.39, 3.23, 1.43, and 1.58 mmol/L in the population with diabetes, respectively. Moreover, 36.92 and 19.10% of the adults had borderline-high and high total cholesterol. The population estimates for borderline-high, high LDL and low HDL cholesterol levels were 25.24, 13.39, and 5.64%, respectively. Meanwhile, borderline high and high triglyceride levels accounted for 16.7 and 17.47% of the population, respectively. CONCLUSIONS: Serum total and LDL cholesterol levels were high in the ≥40 years old population of Shandong Province. Age, gender, glucose metabolism status, body mass index (BMI) and glycosylated hemoglobin (HbA1c) can affect serum lipid and lipoprotein levels.

[Effects and mechanisms of Xiao-Ai-Ping injection on angiogenesis].

This study was designed to investigate the effect of Xiao-Ai-Ping injection on cancer angiogenesis. CCK8 assay and Brd U incorporation immunofluorescence assay were used to detect the effect of Xiao-Ai-Ping injection on HUVECs proliferation; wound healing assay and transwell assay were employed to test the effect of Xiao-Ai-Ping injection on HUVECs migration. The anti-angiogenic effect of Xiao-Ai-Ping injection was examined by tube formation assay, rat aortic ring assay and chicken chorioallantoic membrane(CAM) assay. ELISA assay was used to measure the secretion of vascular endothelial growth factor(VEGF); and the activation of vascular endothelial growth factor receptor 2(VEGFR2) protein and its downstream signaling pathways were examined by Western blot. Our data demonstrated that Xiao-Ai-Ping injection inhibited HUVECs proliferation in a time- and dose-dependent manner, and the IC(50) (mg·m L(-1)) values for 24, 48 and 72 h were 48.7 ± 7.14, 29.1 ±2.25 and 22.0 ± 4.53, individually. Xiao-Ai-Ping injection inhibited HUVECs DNA synthesis and migration. Xiao-Ai-Ping injection suppressed HUVECs tube formation, and reduced microvessel sprouting from rat aortic rings and vessel growth in CAMs. Furthermore, Xiao-Ai-Ping injection attenuated the secretion of VEGF, and inhibited the expression of p-VEGFR2 and phosphorylation of protein kinase B(p-AKT). We conclude that Xiao-Ai-Ping injection inhibits angiogenesis by down-regulation of VEGF signaling and AKT pathway.

Mechanisms of age-related hearing loss at the auditory nerve central synapses and postsynaptic neurons in the cochlear nucleus.

Sound information is transduced from mechanical vibration to electrical signals in the cochlea, conveyed to and further processed in the brain to form auditory perception. During the process, spiral ganglion neurons (SGNs) are the key cells that connect the peripheral and central auditory systems by receiving information from hair cells in the cochlea and transmitting it to neurons of the cochlear nucleus (CN). Decades of research in the cochlea greatly improved our understanding of SGN function under normal and pathological conditions, especially about the roles of different subtypes of SGNs and their peripheral synapses. However, it remains less clear how SGN central terminals or auditory nerve (AN) synapses connect to CN neurons, and ultimately how peripheral pathology links to structural alterations and functional deficits in the central auditory nervous system. This review discusses recent progress about the morphological and physiological properties of different subtypes of AN synapses and associated postsynaptic CN neurons, their changes during aging, and the potential mechanisms underlying age-related hearing loss.

The copper transporter, SLC31A1, transcriptionally activated by ELF3, imbalances copper homeostasis to exacerbate cisplatin-induced acute kidney injury through mitochondrial dysfunction.

Acute kidney injury (AKI) is a common complication of cisplatin chemotherapy, which greatly limits its clinical effect and application. This study explored the function of solute Carrier Family 31 Member 1 (SLC31A1) in cisplatin-induced AKI and its possible mechanism. Mice and HK-2 cells were exposed to cisplatin to establish the in vivo and in vitro AKI models. Cell viability was detected by CCK-8. Mitochondrial and oxidative damage was determined by Mito-Tracker Green staining, mtROS level, ATP production, mitochondrial membrane potential, MDA content and CAT activity. AKI was evaluated by renal function and histopathological changes. Apoptosis was detected by TUNEL and caspase-3 expression. Molecule expression was measured by RT-qPCR, Western blotting, and immunohistochemistry. Molecular mechanism was studied by luciferase reporter assay and ChIP. SLC31A1 level was predominantly increased by cisplatin exposure in AKI models. Notably, copper ion (Cu+) level was enhanced by cisplatin challenge. Moreover, Cu+ supplementation intensified cisplatin-induced cell death, mitochondrial dysfunction, and oxidative stress in HK-2 cells, indicating the involvement of cuproptosis in cisplatin-induced AKI, whereas these changes were partially counteracted by SLC31A1 knockdown. E74 like ETS transcription factor 3 (ELF3) could directly bind to SLC31A1 promoter and promote its transcription. ELF3 was up-regulated and positively correlated with SLC31A1 expression upon cisplatin-induced AKI. SLC31A1 silencing restored renal function, alleviated mitochondrial dysfunction, and apoptosis in cisplatin-induced AKI mice. ELF3 transcriptionally activated SLC31A1 to trigger cuproptosis that drove cisplatin-induced AKI through mitochondrial dysfunction, indicating that SLC31A1 might be a promising therapeutic target to mitigate AKI during cisplatin chemotherapy.

Effects of dural puncture epidural technique with different drug delivery methods for labor analgesia: A randomized controlled clinical trial.

This study aimed to investigate the effect of dural puncture epidural (DPE) combined with small-dose lidocaine for labor analgesia. Parturients were randomly divided into epidural anesthesia (EA), DPE1, and DPE2 groups. In the EA group, 5 mL of 1% lidocaine was administered via conventional L2-L3 puncture catheterization; in the DPE1 group, epidural drug was administered after catheterization using the DPE technique; in the DPE2 group, epidural puncture drug was administered through the epidural puncture needle before catheterization using the DPE technique. The primary outcome was the onset time of analgesia. The secondary outcomes included the numerical rating scale (NRS) scores during uterine contraction before bolus injection of experimental dose (T0) and the second time (T1), the fifth time (T2) and the tenth time (T3) after bolus injection of experimental dose; NRS scores at the second stage of labor (T4) and during perineal suture (T5); operation time of anesthesia; puncture related complications; anesthesia related complications; delivery outcome; use of local anesthesia during vaginal suture; and Apgar score of the neonates. There were 115 women included. The onset time in the DPE2 group was markedly shorter than in the EA and DPE1 groups (P < .001). The NRS scores in the DEP2 group at T1 and T4 were significantly lower than in the EA and DEP1 groups (P < .001). The overall incidence of puncture related complications in the DEP1 and DEP2 groups was markedly higher than in the EA group (P < .05). In dural puncture epidural analgesia, when the experimental dose was injected directly through the epidural puncture needle, the onset time was shorter and the analgesic effect was better as compared to the injection of test dose after inserting the epidural catheter.

Apical-basal distribution of different subtypes of spiral ganglion neurons in the cochlea and the changes during aging.

Sound information is transmitted from the cochlea to the brain mainly by type I spiral ganglion neurons (SGNs), which consist of different subtypes with distinct physiological properties and selective expression of molecular markers. It remains unclear how these SGN subtypes distribute along the tonotopic axis, and whether the distribution pattern changes during aging that might underlie age-related hearing loss (ARHL). We investigated these questions using immunohistochemistry in three age groups of CBA/CaJ mice of either sex, including 2-5 months (young), 17-19 months (middle-age), and 28-32 months (old). Mouse cochleae were cryo-sectioned and triple-stained using antibodies against Tuj1, calretinin (CR) and calbindin (CB), which are reportedly expressed in all type I, subtype Ia, and subtype Ib SGNs, respectively. Labeled SGNs were classified into four groups based on the expression pattern of stained markers, including CR+ (subtype Ia), CB+ (subtype Ib), CR+CB+ (dual-labeled Ia/Ib), and CR-CB- (subtype Ic) neurons. The distribution of these SGN groups was analyzed in the apex, middle, and base regions of the cochleae. It showed that the prevalence of subtype Ia, Ib and dual-labeled Ia/Ib SGNs are high in the apex and low in the base. In contrast, the distribution pattern is reversed in Ic SGNs. Such frequency-dependent distribution is largely maintained during aging except for a preferential reduction of Ic SGNs, especially in the base. These findings corroborate the prior study based on RNAscope that SGN subtypes show differential vulnerability during aging. It suggests that sound processing of different frequencies involves distinct combinations of SGN subtypes, and the age-dependent loss of Ic SGNs in the base may especially impact high-frequency hearing during ARHL.

Dendritic Degeneration and Altered Synaptic Innervation of a Central Auditory Neuron During Age-related Hearing Loss.

Cellular morphology and synaptic configuration are key determinants of neuronal function and are often modified under pathological conditions. In the first nucleus of the central auditory system, the cochlear nucleus (CN), principal bushy neurons specialize in processing temporal information of sound critical for hearing. These neurons alter their physiological properties during aging that contribute to age-related hearing loss (ARHL). The structural basis of such changes remains unclear, especially age-related modifications in their dendritic morphology and the innervating auditory nerve (AN) synapses. Using young (2-5 months) and aged (28-33 months) CBA/CaJ mice of either sex, we filled individual bushy neurons with fluorescent dye in acute brain slices to characterize their dendritic morphology, followed by immunostaining against vesicular glutamate transporter 1 (VGluT1) and calretinin (CR) to identify innervating AN synapses. We found that dendritic morphology of aged bushy neurons had significantly reduced complexity, suggesting age-dependent dendritic degeneration, especially in neurons with predominantly non-CR-expressing synapses on the soma. These dendrites were innervated by AN bouton synapses, which were predominantly non-CR-expressing in young mice but had increased proportion of CR-expressing synapses in old mice. While somatic AN synapses degenerated substantially with age, as quantified by VGluT1-labeled puncta volume, no significant difference was observed in the total volume of dendritic synapses between young and old mice. Consequently, synaptic density on dendrites was significantly higher in old mice. The findings suggest that dendritic degeneration and altered synaptic innervation in bushy neurons during aging may underlie their changed physiological activity and contribute to the development of ARHL.

Self-template synthesis of mesoporous and biodegradable Fe3O4 nanospheres as multifunctional nanoplatform for cancer therapy.

Superparamagnetic Fe3O4 nanospheres have demonstrated great potential as important components in nanomedicine for cancer imaging and therapy. One of the major obstacles that impedes their application is the slow degradation of ingested Fe3O4 nanospheres, which potentially causes long-term health risks. To tackle this issue, we proposed to fabricate Fe3O4 nanospheres with mesoporous structure via a simple self-template etching method. The mesoporous Fe3O4 nanospheres not only offered large specific surface area and weak-acidic responsive degradability, but also exhibited T2-weighted magnetic resonance contrast enhancement and magnetic targeting, which made them possible to serve as excellent cancer therapeutic nanoplatform. Both inorganic photothermal therapeutic Au nanoparticles and organic chemotherapeutic doxorubicin hydrochloride were demonstrated to be successfully loaded onto such kind of nanoplatform, and the hybrid nanomedicine demonstrated synergistic photothermal and chemotherapeutic activity for tumor elimination under near infrared irradiation and improved biodegradability in weak acidic tumor microenvironment. We believe that this study paved a simple way for designing multifunctional Fe3O4-based biodegradable nanomedicine.

YB-1 Expression Is Associated with Lymph Node Metastasis and Drug Resistance to Adriamycin in Breast Cancer.

Background: Breast cancer (BC) is the most common malignant tumor among females. Although there are multiple treatments for breast cancer, many patients still face the dilemma of drug resistance after multiline treatment. It would be greatly helpful for clinical work to identify additional and improved prognostic predictors. Y-box binding protein-1 (YB-1) is a member of the cold shock protein family, and patients with overexpression of YB-1 have a worse prognosis. Methods: This study collected 48 specimens from 48 patients with breast cancer and analyzed the clinicopathological characteristics of the patients. Immunohistochemistry, immunofluorescence, cell viability analysis, tumor spheroid formation and cell morphology, cell invasion, cycle analysis, qRT-PCR, Western blot, and tumorigenicity in BALB/c nude mice were performed to verify the results. Results: We found that patients with overexpression of YB-1 were related to lymph node metastasis and the patients' age tended to be young. Because of the short follow-up time, a survival analysis could not be performed. Based on the results of in vitro and in vivo experiments, this study indicated that breast cancer cells with overexpression of YB-1 had stronger proliferation, migration, and invasion abilities than cells with low expression of YB-1. Compared with cells with low expression of YB-1, the proliferation, migration, and invasion abilities of YB-1 overexpressed cells were not significantly affected by adriamycin. Conclusion: This suggested that breast cancer cells with overexpression of YB-1 were resistant to adriamycin. Therefore, YB-1 is associated with lymph node metastasis of breast cancer cell. YB-1 could be a prognostic, predictive factor and a novel therapeutic target of BC.

Hepatic artery intervention combined with immune-targeted therapy is superior to sequential therapy in BCLC-C hepatocellular carcinoma.

BACKGROUND: Hepatic artery intervention combined with immunotarget therapy exerts excellent disease control and prolongs survival. However, the arrangement of hepatic artery intervention and systemic therapy confuses clinical decisions. METHODS: A two-center, retrospective clinical study was approved by the Institutional Ethics Committee. From December 2018 to February 2022, patients with Barcelona Clinic Liver Cancer stage C (BCLC-C) hepatocellular carcinoma (HCC) who received targeted therapy plus PD-1 inhibitors with or without hepatic artery intervention were included. According to the treatment mode, the patients were assigned to three groups: initial hepatic artery intervention combined with immunotarget therapy, immunotarget therapy sequential hepatic artery interventional therapy, and immunotarget therapy only. The survival, response, and adverse events were compared among the three groups. Subgroup analysis and univariate and multivariate prognostic analyses were also evaluated. RESULTS: The median follow-up time was 18.3 months (95% CI 16.7 to 20.0 months). A total of 163 patients with BCLC-C stage HCC were assigned to three groups: initial hepatic artery intervention plus PD-1 inhibitors plus targeted therapy (HPT, n = 66), PD-1 inhibitors plus targeted therapy followed by hepatic artery intervention (PTH, n = 56) and PD-1 inhibitors plus targeted therapy (PT, n = 41). The median progression-free survival was 8.37 months (95% CI 6.35-10.39) with HPT versus 5.3 months (95% CI 3.48-7.12) with PTH versus 6.33 months (95% CI 3.75-8.92) with PT. The progression-free survival of the HPT group was better than that of the PTH group (HR 0.66, 95% CI 0.45-0.97, p = 0.027) and PT group (HR 0.60, 95% CI 0.39-0.92, p = 0.01). The median overall survival was 14.6 months (95% CI 10.6-18.7) with HPT, 10.0 months (95% CI 8.2-11.8) with PTH and 11.3 months (95% CI 8.3-14.3) with PT. The 1-year overall survival (OS) rates in the HPT, PTH and PT groups were 50%, 33.9%, and 34.1%, respectively. Overall survival was significantly longer in the HTP group than in the PT group (HR 0.60, 95% CI 0.361-0.996, p = 0.032). Compared with the PTH group, the overall survival of the HTP group had a prolonged survival trend (HR 0.66, 95% CI 0.416-1.032, p = 0.059). All treatment modalities were deemed equally safe. Multivariate analysis suggested that the mode of treatment, albumin level, Child‒Pugh grade and hepatectomy history were independent prognostic factors for BCLC-C HCC patients. CONCLUSIONS: Initial hepatic artery intervention combined with immunotarget therapy gained survival benefits with tolerable side effects compared with immunotarget sequential hepatic artery intervention and immunotarget therapy alone. Multivariate analysis suggested that liver reserve function was closely correlated with prognosis.

Resveratrol inhibits TGF-ß1-induced EMT in gastric cancer cells through Hippo-YAP signaling pathway.

OBJECTIVE: To investigate the effects of resveratrol (RSVL) on epithelial-mesenchymal transition (EMT) and biological behaviors of gastric cancer cells. METHODS: SGC-7901 cells were treated with RSVL, followed by TGF-ß1 treatment for induction of EMT. Cell proliferation was tested by MTT assay, migration and invasion by Transwell and scratch assays, and Hippo-YAP signaling pathway activation by immunofluorescence. The RNA and protein expressions of E-cadherin, Vimentin, N-cadherin, and Snail were detected by qPCR and Western blot. A tumor model was constructed to examine the effect of RSVL on gastric tumor growth. RESULTS: RSVL inhibited the migration, invasion, and growth of gastric cancer cells in concentration- and time-dependent manners. RSVL inhibited TGF-ß1-induced EMT of gastric cancer cells, which might relate to inactivation of the Hippo-YAP pathway. In the mouse tumor model, RSVL inhibited the EMT process by suppressing the Hippo-YAP pathway. CONCLUSION: RSVL inhibited EMT of gastric cancer cells probably by weakening the Hippo-YAP signaling pathway.

Diagnostic utility of corneal confocal microscopy in type 2 diabetic peripheral neuropathy.

AIMS/INTRODUCTION: The early pathological changes of diabetic peripheral neuropathy (DPN) are mainly small nerve fiber injuries. Corneal confocal microscopy (CCM) is an easy, rapid, non-invasive and repeatable technique to detect the damage of small nerve fibers. The purpose of this study was to explore the application of CCM in DPN and other chronic complications of type 2 diabetes mellitus. MATERIALS AND METHODS: A total of 220 individuals (48 normal healthy control participants and 172 patients with type 2 diabetes mellitus) were included in the study. All participants were assessed and scored for neurological symptoms and neurological deficits, quantitative sensory test, neuroelectrophysiological test, and CCM. RESULTS: Corneal nerve fiber density, corneal nerve fiber length and corneal nerve branch density were significantly reduced in patients with type 2 diabetes mellitus compared with normal healthy control subjects (P < 0.001, P < 0.001 and P < 0.001, respectively). In the DPN group, corneal nerve fiber density, corneal nerve branch density and corneal nerve fiber length were significantly lower than for patients without DPN (P < 0.001, P < 0.001 and P < 0.001, respectively). Receiver operating characteristic analysis showed that the optimal cut-off values were 24.68, 39 and 15.315, respectively, in which corneal nerve fiber density and corneal nerve fiber length had moderate sensitivity and specificity. CONCLUSION: This study provides more support for the clinical use of CCM to diagnose type 2 diabetes mellitus-related complications, especially DPN.

Lipin1 Alleviates Autophagy Disorder in Sciatic Nerve and Improves Diabetic Peripheral Neuropathy.

Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes, and its neural mechanisms underlying the pathogenesis remain unclear. Autophagy plays an important role in neurodegenerative diseases and nerve tissue injury. Lipin1 is a phosphatidic acid phosphatase enzyme that converts phosphatidic acid (PA) into diacylglycerol (DAG), a precursor of triacylglycerol and phospholipids which plays an important role in maintaining normal peripheral nerve conduction function. However, whether Lipin1 involved in the pathogenesis of DPN via regulation of autophagy is not elucidated. Here, we show that the Lipin1 expression was downregulated in streptozotocin (STZ)-induced DPN rat model. Interestingly, STZ prevented DAG synthesis, and resulted in autophagic hyperactivity, effects which may increase the apoptosis of Schwann cells and lead to demyelination in sciatic nerve in DPN rats. More importantly, upregulation of lipin1 in the DPN rats ameliorated autophagy disorders and pathological changes of the sciatic nerve, which associated with the increase of the motor nerve conductive velocity (MNCV) in DPN rats. In contrast, knockdown of lipin1 exacerbates neuronal abnormalities and facilitates the genesis of DPN phenotypes in rats. In addition, overexpression of lipin1 in RSC96 cells also significantly decreased the autophagic hyperactivity and apoptosis induced by hyperglycemia. These results suggest that lipin1 may exert neuroprotection within the sciatic nerve anomalies and may serve as a potential therapeutic target for the treatment of DPN.

Neuroprotective Effects of Fluoxetine Against Chronic Stress-Induced Neural Inflammation and Apoptosis: Involvement of the p38 Activity.

Depression is considered a widespread neuropsychiatric disease associated with neuronal injury within specific brain regions. Fluoxetine, a selective serotonin reuptake inhibitor, has been widely used in depressed patients. Recently, fluoxetine has demonstrated neuroprotective effects apart from the effect on serotonin. However, the underlying mechanism involved in this neuroprotection remains unclear, in particular, whether fluoxetine exerts antidepressant effects via protecting against neuronal injury. Here, we found that treatment with fluoxetine (10 mg/kg, i.p.) for 2 weeks ameliorated depression-like behaviors in a chronic unpredictable mild stress (CUMS)-induced rat model of depression and was accompanied with an alleviation of glia activation and inhibition of interleukin-1ß (IL-1ß), interferon gamma (IFN-γ), and tumor necrosis factor-α (TNF-α) expression in the hippocampal dentate gyrus (DG) region. Meanwhile, CUMS rats treated with fluoxetine showed reductions in neuronal apoptosis and a downregulation of the apoptotic protein Bax, cleaved caspase 3, and caspase 9 levels. These effects appear to involve a downregulation of p38 mitogen-activated protein kinase (MAPK) signaling within the DG hippocampus as the specific inhibitor of p38 MAPK, SB203580, significantly suppressed apoptosis, as well as ameliorated depressive behaviors resulting from CUMS exposure. Moreover, fluoxetine could rescue neuronal deterioration and depression-like phenotypes caused by overexpression of p38 in DG. This finding extends our knowledge on the antidepressant-like effects of fluoxetine, which appear to at least partially profit from neuroprotection against inflammation and neuronal apoptosis via downregulation of the p38 MAPK pathway. The neuroprotective mechanisms of fluoxetine may provide some novel therapeutic avenues for stress-related neurological diseases.

A neuronal wiring platform through microridges for rationally engineered neural circuits.

Precisely engineered neuronal circuits are promising for both fundamental research and clinical applications. However, randomly plating thousands of cells during neural network fabrication remains a major technical obstacle, which often results in a loss of tracking in neurons' identities. In this work, we demonstrated an accurate and unique neural wiring technique, mimicking neurons' natural affinity to microfibers. SU-8 microridges, imitating lie-down microfibers, were photolithographically patterned and then selectively coated with poly-l-lysine. We accurately plated Aplysia californica neurons onto designated locations. Plated neurons were immobilized by circular microfences. Furthermore, neurites regrew effectively along the microridges in vitro and reached adjacent neurons without undesirable crosstalks. Functional chemical synapses also formed between accurately wired neurons, enabling two-way transmission of electrical signals. Finally, we fabricated microridges on a microelectrode array. Neuronal spikes, stimulation-evoked synaptic activity, and putative synaptic adaption between connected neurons were observed. This biomimetic platform is simple to fabricate and effective with neurite pathfinding. Therefore, it can serve as a powerful tool for fabricating neuronal circuits with rational design, organized cellular communications, and fast prototyping.

Lipin1 Is Involved in the Pathogenesis of Diabetic Encephalopathy through the PKD/Limk/Cofilin Signaling Pathway.

Diabetic encephalopathy is a type of central diabetic neuropathy resulting from diabetes mainly manifested as cognitive impairments. However, its underlying pathogenesis and effective treatment strategies remain unclear. In the present study, we investigated the effect of Lipin1, a phosphatidic acid phosphatase enzyme, on the pathogenesis of diabetic encephalopathy. We found that in vitro, Lipin1 exerts protective effects on high glucose-induced reductions of PC12 cell viability, while in vivo, Lipin1 is downregulated within the CA1 hippocampal region in a type I diabetes rat model. Increased levels of Lipin1 within the CA1 region are accompanied with protective effects including amelioration of dendritic spine and synaptic deficiencies, phosphorylation of the synaptic plasticity-related proteins, LIM kinase 1 (p-limk1) and cofilin, as well as increases in the synthesis of diacylglycerol (DAG), and the expression of phosphorylated protein kinase D (p-PKD). These effects are associated with the rescue of cognitive disorders as shown in this rat model of diabetes. In contrast, knockdown of Lipin1 within the CA1 region enhanced neuronal abnormalities and the genesis of cognitive impairment in rats. These results suggest that Lipin1 may exert neuroprotective effects involving the PKD/Limk/Cofilin signaling pathway and may serve as a potential therapeutic target for diabetic encephalopathy.