Abstract Luteolin is a flavonoid found in high concentrations in celery and green pepper, and acts as a neuroprotectant. PSMC5 (proteasome 26S subunit, ATPase 5) protein levels were reduced after luteolin stimulation in activated microglia. We aimed to determine whether regulating PSMC5 expression could inhibit neuroinflammation, and investigate the underlying mechanisms.BV2 microglia were transfected with siRNA PSMC5 before the addition of LPS (lipopolysaccharide, 1.0 µg/ml) for 24 h in serum free DMEM. A mouse model of LPS-induced cognitive and motor impairment was established to evaluate the neuroprotective effects of shRNA PSMC5. Intracerebroventricular administration of shRNA PSMC5 was commenced 7 days prior to i.p. injection of LPS (750 μg/kg). Treatments and behavioral experiments were performed once daily for 7 consecutive days. Behavioral tests and pathological/biochemical assays were performed to evaluate LPS-induced hippocampal damage. Molecular dynamics simulation was used to confirm the interaction between PSMC5 and TLR4 (Toll-like receptor 4) in LPS-stimulated BV2 microglia. SiRNA PSMC5 inhibited BV2 microglial activation, and suppressed the release of inflammatory factors (IL-1β, COX-2, PGE2, TNF-α, and iNOS) upon after LPS stimulation in BV2 microglia. LPS increased IκB-α and p65 phosphorylation, which was attenuated by siRNA PSMC5. Behavioral tests and pathological/biochemical assays showed that shRNA PSMC5 attenuated LPS-induced cognitive and motor impairments, and restored synaptic ultrastructure and protein levels in mice. ShRNA PSMC5 reduced pro-inflammatory cytokine (TNF-α, IL-1β, PGE2, and NO) levels in the serum and brain, and relevant protein factors (iNOS and COX-2) in the brain. Furthermore, shRNA PSMC5 upregulated the anti-inflammatory mediators interleukin IL-4 and IL-10 in the serum and brain, and promoted a pro-inflammation-to-anti-inflammation phenotype shift in microglial polarization. Mechanistically, shRNA PSMC5 significantly alleviated LPS-induced TLR4 expression. The polarization of LPS-induced microglial pro-inflammation phenotype was abolished by TLR4 inhibitor and in the TLR-4−/− mouse, as in shRNA PSMC5 treatment. PSMC5 interacted with TLR4 via the amino sites Glu284, Met139, Leu127, and Phe283. PSMC5 site mutations attenuated neuroinflammation and reduced pro-inflammatory factors by reducing TLR4-related effects, thereby reducing TLR4-mediated MyD88 (myeloid differentiation factor 88)-dependent activation of NF-κB. PSMC5 could be an important therapeutic target for treatment of neurodegenerative diseases involving neuroinflammation-associated cognitive deficits and motor impairments induced by microglial activation. Graphical Abstract

Oxidative stress is one of the pathological mechanisms of Alzheimer’s disease (AD), and ferroptosis has been determined to be involved in neurodegenerative diseases such as AD. Senegenin (Sen) prevents oxidative damage in nerve cells via a mechanism that may be highly related to ferroptosis. However, the mechanism of ferroptosis pathway involvement in AD is unclear. In this study, we established a model of PC12 cytotoxic injury induced by Aβ25–35, and we detected the level of oxidative damage, MMP, and ferroptosis-related protein expression. The results showed that, compared with control group, the level of ROS increased, GPX activities decreased, and MDA levels increased in Aβ25–35 group. Aβ25–35 could induce mitochondrial depolarization in PC12 cells and Fer-1 could not reverse this damage. WB revealed that Aβ25–35 group had increased ACSL4 and PEBP1 proteins, and decreased GPX4 protein. After adding Sen in the model, the level of oxidative damage was reduced, and mitochondrial depolarization was reversed compared with Aβ25–35 group. WB suggested that the expression of ACSL4 and PEBP1 proteins decreased, and the expression of GPX4 protein increased by Sen treatment. In conclusion, we found that Sen exhibits strong neuroprotective activity against Aβ25–35 induced oxidative damage and lipid metabolic associated with ferroptosis. Inhibiting nerve cell ferroptosis might facilitate the future development of strategies to AD.

RhoGDIα is an inhibitor of RhoGDP dissociation that involves in Aβ metabolism and NFTs production in Alzheimer's disease (AD) by regulating of RhoGTP enzyme activity. Our previous research revealed that RhoGDIα, as the target of Polygala saponin (Sen), might alleviate apoptosis of the nerve cells caused by hypoxia/reoxygenation (H/R). To further clarify the role of RhoGDIα in the generation of NFTs, we explored the relationship between RhoGDIα and Tau. We found out that RhoGDIα and Tau can bind with each other and interact by using coimmunoprecipitation (Co-IP) and GST pulldown methods in vitro. This RhoGDIα-Tau partnership was further verified by using immunofluorescence colocalization and fluorescence resonance energy transfer (FRET) approaches in PC12 cells. Using the RNA interference (RNAi) technique, we found that the RhoGDIα may be involved in an upstream signaling pathway for Tau. Subsequently, in Aβ25-35- and H/R-induced PC12 cells, forced expression of RhoGDIα via cDNA plasmid transfection was found to reduce the hyperphosphorylation of Tau, augment the expression of bcl-2 protein, and inhibit the expression of Bax protein (reducing the Bax/bcl-2 ratio) and the activity of caspase-3. In mouse AD and VaD models, forced expression of RhoGDIα via injection of a viral vector (pAAV-EGFP-RhoGDIα) into the lateral ventricle of the brain alleviated the pathological symptoms of AD and VaD. Finally, GST pulldown confirmed that the binding sites on RhoGDIα for Tau were located in the range of the ΔC33 fragment (aa 1–33). These results indicate that RhoGDIα is involved in the phosphorylation of Tau and apoptosis in AD and VaD. Overexpression of RhoGDIα can inhibit the generation of NFTs and delay the progress of these two types of dementia.

Traditional Chinese medicine (TCM) for anti?abortion is based on the theory of gynecology of TCM, which aims to prevent and treat abdominal pain during pregnancy, fetal leakage, uneasy fetal movement, and fetal atrophy. Because of the complexity of the ingredients of Chinese Materia Medica, and the imprecise intervention mechanism for tocolysis, further investigation about the effects of Chinese herbs and their components on tocolysis by utilizing advanced technologies is required to be made. All the information available about TCM and its effects on pregnant women and fetuses was collected via electronic search using Web of Science, PubMed, and CNKI, and a library search was performed to locate classic herbal medicine books. The active ingredients in TCM were screened with the help of Traditional chinese medicine systems pharmacology database and analysis platform (TCMSP). The keywords being used included herbal names, pharmacology, pregnancy, threatened abortion, and fetus. Modern pharmacological studies have shown that TCM mainly prevents threatened abortion by a direct effect on the pregnant woman's immune system, sex hormones such as estrogen and progesterone, the uterus and the endometrium, and the decidual tissue such as the placenta. It may also address pregnancy complications due to advanced maternal age, infection, polycystic ovary syndrome, diabetes, and mental disorders caused by threat of a miscarriage. TCM protects against spontaneous miscarriage, but its mechanisms are largely unknown. This research applies scientific methods to characterize and examine the effective components of TCM and their application to lower the risk of abortion to the pregnant women and fetuses.

目的:分析肾间质纤维化(RIF)早期的蛋白质组表达变化情况,为探讨干预RIF的新靶点奠定基础.方法:(1)48只雄性Wistar大鼠,随机分为正常对照(control)组(6只)、假手术(sham)组(6只)和单侧输尿梗阻(UUO)模型组(36只).UUO组行右侧输尿管结扎,并分别于术后第3、7、11、14、21和28天各处死6只,取肾脏标本行HE染色和Masson染色,光镜下观察病理变化;control组不作任何处理,sham组开腹后只分离右输尿管但不结扎,两组均于第28天取肾脏标本作病理观察;(2)取UUO术后第7天大鼠梗阻侧和健侧肾组织的蛋白质提取液行双向凝胶电泳,两侧对照找出差异蛋白质,选取部分差异蛋白点进行质谱鉴定;(3)Western blot检测UUO大鼠肾脏组织膜联蛋白A5(annexin A5)表达的动态变化.结果:(1)UUO各组梗阻肾脏逐渐出现肾小管扩张、炎症细胞浸润、肾小管上皮细胞萎缩、间质胶原纤维沉积等变化,其中,肾梗阻后第7天开始出现间质纤维化;(2)与健侧肾比较,UUO术后第7天的梗阻侧肾出现≥1.5倍的差异蛋白质166个,其中上调81个,下调85个,质谱成功鉴定出19种差异蛋白质;(3)Western blot显示,各时段UUO组大鼠梗阻侧肾组织中annexin A5表达均明显高于sham组(P<0.05),其中以梗阻第3天组的表达量最高,随后逐渐下降,但仍高于sham组.结论:(1)RIF早期存在大量表达差异的蛋白质;(2)RIF的annexin A5表达显著增加,可能与某些病理变化存在密切关系.

BackgroundDobutamine (DOB) has been recommended as the first-line inotrope for septic patients with low cardiac output, but its long-term impact on intrinsic myocardial dysfunction during sepsis remains unclear. This study investigated the long-term effect of DOB on intrinsic myocardial function and cardiomyocyte apoptosis in sepsis.MethodsMale Sprague-Dawley rats were randomly divided into sham and cecal ligation and puncture (CLP) groups. The intrinsic myocardial function and other organ functions were measured at different time points, the inflammatory response and serum biomarkers of myocardial injury were also determined. In separate experiments, the effect of DOB (5 or 10 µg/kg) treatment on survival, intrinsic myocardial function, serum and myocardial cytokines and myocardial apoptosis were measured in septic rats.ResultsThe mortality rate of septic rats was 70% on day 10 after CLP. At 6 h after CLP, the left ventricular ± dP/dt were significantly depressed, serum tumor necrosis factor (TNF) –α level, cardiac TNF-α, intercellular adhesion molecule and vascular cell adhesion molecule-1 (VCAM-1) mRNA, and VCAM-1 protein levels were increased, but not serum cTnI, N-terminal pro-brain natriuretic peptide (NT-proBNP), heart-type fatty acid-binding protein (H-FABP), creatinine and urea nitrogen concentrations as well as lung wet-dry weight ratios in CLP group compared with those in sham group. At 9 h after CLP, serum alanine aminotransferase and aspartate aminotransferase activities were higher in CLP rats than controls. At 6 h after CLP, treatment with DOB did not affect the left ventricular ± dP/dt, the levels of TNF-α, interleukin (IL) − 1β and IL-6 in the serum and myocardium as well as cardiomyocyte apoptosis at 20 h after CLP. However, administration of 10.0 µg/kg DOB at 6 h after CLP significantly increased serum IL-10 level and improved survival in septic rats.ConclusionsThe intrinsic myocardial depression occurs earlier than hepatic and renal dysfunction in severe sepsis and serum cTnI, NT-proBNP and H-FABP are not suitable as an early biomarker for this kind of cardiac dysfunction. For septic rats, DOB treatment in the presence of intrinsic myocardial dysfunction neither improves myocardial function nor attenuates myocardial inflammation and cardiomyocyte apoptosis at the later stage of sepsis.

目的:利用脓毒症大鼠模型,比较常规超声和组织多普勒超声指标在早期诊断脓毒症大鼠心肌内在收缩与舒张功能障碍中的价值.方法:利用盲肠结扎穿孔(CLP)建立脓毒症大鼠模型,22只大鼠随机分成CLP组与假手术组,每组11只.利用ELISA和Western blot检测肿瘤坏死因子α(TNF-α)、细胞间黏附分子1(ICAM-1)和血管细胞黏附分子1(VCAM-1)的表达水平;离体心脏灌流、常规超声心动图和心脏组织多普勒成像测定心脏收缩与舒张功能.结果:与假手术组比较,CLP术后6 h,大鼠血清中TNF-α水平及左心室ICAM-1和VCAM-1表达显著升高,左心室±dp/dtmax显著降低,左心室每搏输出量与舒张末期容积显著降低,但左室射血分数的差异没有统计学显著性,二尖瓣血流速度E波峰值和A波峰值显著降低,二尖瓣环舒张早期运动速度E'波峰值和二尖瓣环舒张晚期运动速度A'波峰值显著降低,而E/E'比值的差异没有统计学显著性.相关分析显示,E'波峰值和A'波峰值分别与?dp/dtmax呈正相关(r分别为0.460和0.520,P<0.05).结论:组织多普勒成像可以有效评价脓毒症早期心肌内在舒张功能障碍,E'与A'峰值可以作为检测左室心肌舒张功能障碍的指标.

Astaxanthin (Ast) is an effective neuroprotective and antioxidant compound used to treat Alzheimer's disease (AD); however, the underlying in vivo molecular mechanisms remain unknown. In this study, we report that Ast can activate the mammalian target of rapamycin (mTOR) pathway in the 8-month-old APP/PS1 transgenic mouse model of AD. Our results suggest that Ast could ameliorate the cognitive defects in APP/PS1 mice by activating the mTOR pathway. Moreover, mTOR activation perturbed the mitochondrial dynamics, increased the synaptic plasticity after 21 days of treatment with Ast (10 mg/kg/day), and increased the expression of Aβ-degrading enzymes, mitochondrial fusion, and synapse-associated proteins and decreased the expression of mitochondrial fission proteins. Intraperitoneal injection of the mTOR inhibitor, rapamycin, abolished the effects of Ast. In conclusion, Ast activates the mTOR pathway, which is necessary for mitochondrial dynamics and synaptic plasticity, leading to improved learning and memory. Our results support the use of Ast for the treatment of cognitive deficits. Graphical abstract In summary, Ast ameliorates cognitive deficits via facilitating the mTOR-dependent mitochondrial dynamics and synaptic damage, and reducing Aβ accumulation. This model supports the use of Ast for the treatment of cognitive deficits.

Oxidative stress is a potential pathological mechanism of Alzheimer’s disease (AD). Berberine (BBR) can improve antioxidative capacity and inhibit Aβ protein aggregation and tau protein hyperphosphorylation in AD, and stem cell therapy is also increasingly recognized as a therapy for AD. Bone marrow mesenchymal stem cells (BMSCs) have many advantages, as they exhibit antioxidant and anti-inflammatory activity and secrete a variety of neurotrophic factors, and play important roles in neurodegenerative disease treatment. In this study, we investigated the antioxidant effects of secretions from BMSCs pretreated with BBR on tert -butyl hydroperoxide ( t -BHP)–damaged neurons. We demonstrated that BBR can enhance BMSC viability and the secretion of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), both of which are vital neurotrophic factors that maintain neuronal growth. Moreover, conditioned medium from BBR-treated BMSCs (BBR-BMSC-CM) reduced reactive oxygen species (ROS) production, attenuated a decrease in the mitochondrial membrane potential, and ameliorated neuronal apoptosis by decreasing levels of the apoptotic proteins Bax/Bcl-2, cytochrome c, and cleaved caspase-3/caspase-3. In addition, increased synaptophysin (SYP) and postsynaptic density protein 95 (PSD95) levels indicated that neuronal synaptic function was restored. Further study revealed that BBR-BMSC-CM activated the antioxidant proteins Keap1, Nrf2, and HO-1. In conclusion, our results showed that BBR-BMSC-CM attenuated apoptosis and oxidative damage in neurons by activating the Keap1-Nrf2-HO-1 signaling pathway. Taken together, these results also suggest BBR as a drug to stimulate the secretion of nutritional cytokines with the potential to treat AD.

Abstract The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a serious threat to global public health and there is currently no effective antiviral therapy. It has been suggested that chloroquine (CQ) and hydroxychloroquine (HCQ), which were primarily employed as prophylaxis and treatment for malaria, could be used to treat COVID-19. CQ and HCQ may be potential inhibitors of SARS-CoV-2 entry into host cells, which are mediated via the angiotensin-converting enzyme 2 (ACE2), and may also inhibit subsequent intracellular processes which lead to COVID-19, including damage to the cardiovascular (CV) system. However, paradoxically, CQ and HCQ have also been reported to cause damage to the CV system. In this review, we provide a critical examination of the published evidence. CQ and HCQ could potentially be useful drugs in the treatment of COVID-19 and other ACE2 involved virus infections, but the antiviral effects of CQ and HCQ need to be tested in more well-designed clinical randomized studies and their actions on the CV system need to be further elucidated. However, even if it were to turn out that CQ and HCQ are not useful drugs in practice, further studies of their mechanism of action could be helpful in improving our understanding of COVID-19 pathology.

Sepsis-associated encephalopathy (SAE) is a common and serious complication of sepsis, which is thought to be caused by neuroinflammation. In our previous study, ubiquitin-specific protease 8 (USP8), was reported to regulate inflammation in vitro. In the current study, we investigated whether increased USP8 expression would ameliorate the cognitive and motor impairments induced by cecal ligation and puncture (CLP) in mice, a model of SAE. Male adult mice were randomly divided into four groups: control, sham, CLP, and CLP + USP8 groups. The CLP + USP8 mice showed reduced weight loss on day 4 post-CLP, with a slight increase noted on day 7. The mortality rate in the CLP group was 70% 48 h after CLP; however, USP8 significantly improved survival after CLP. USP8 modulated the neurobehavioral scores in CLP mice. Our results also indicate that USP8 attenuated the CLP-induced cognitive and motor impairments, based on the performance of mice in the Morris water maze (MWM), pole-climbing, and wire suspension tests. USP8 suppressed the release of pro-inflammatory mediators, including prostaglandin E-2 (PGE(2)) in the serum and nitric oxide (NO) in brain tissue, as well as levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in brain tissue. Immunofluorescence experiments revealed that USP8 inhibited CLP-induced increases in microglial size and density in the hippocampus, and protected hippocampal neurons. Our findings indicate that neuroinflammation occurs in the brains of CLP mice, and that USP8 exerts protective effects against CLP-induced neuroinflammation and cognitive and motor impairments, which may aid in the development of novel therapeutic strategies for SAE.

BACKGROUND/PURPOSE:Ultraviolet (UV) A (315-400 nm) is the UV light that most frequently reaches the Earth's surface and can penetrate the epidermis through to the dermis, causing various issues, including skin aging and skin cancer. The results of our previous studies have shown that the flavonoid monomer cyanidin-3-o-glucoside (C3G) can effectively inhibit primary human dermal fibroblast (HDF) oxidative damage and apoptosis caused by UVA radiation. Many flavonoids can regulate the level of autophagy. However, whether C3G inhibits UVA-induced oxidative damage to primary HDFs by regulating autophagy levels remains unclear. METHODS AND RESULTS:In this study, we used different doses (0-12 J/cm2 ) of UVA to irradiate cells and showed that the expression levels of autophagy-related gene 5 (Atg5) and microtubule-associated protein 1 light chain 3 (LC3)-II in primary HDFs first increased and then decreased. The expression of Atg5 and LC3-II was significantly decreased under 12 J/cm2 (light-damage model). C3G increased the levels of Atg5 and LC3-II. Primary HDFs were pretreated with C3G, followed by treatment with the autophagy inhibitor 3-methyladenine (3-MA) after 12 J/cm2 UVA irradiation. The inhibitory effects of C3G on morphological changes, oxidative damage, and apoptosis in primary HDFs induced by UVA were significantly decreased. CONCLUSION:C3G can inhibit UVA-induced damage to primary HDFs by inducing autophagy. These results provide a theoretical basis for the application of natural compounds to resist light damage to the skin in the future.

目的:建立脓毒症相关性脑病(sepsis-associated encephalopathy,SAE)小鼠模型并对其认知功能障碍进行初步研究.方法:选取8～10周龄SPF级雄性C57BL/6J小鼠.第1部分实验将小鼠随机分为4组,即正常对照组,盲肠结扎穿孔术(cecal ligation and puncture,CLP)1组和CLP2组(分别用7号和12号针头行小鼠腹腔CLP)和假手术组(小鼠仅开腹分离盲肠).第2部分实验将小鼠随机分为3组,即正常对照组,假手术组和CLP组.采用Kaplan-Meier法分析小鼠术后存活率;神经行为学评分评价小鼠的神经行为变化;Morris水迷宫实验和避暗实验检测小鼠的认知记忆功能变化;爬杆实验和悬挂实验测试小鼠的运动协调性;ELISA法检测小鼠血清前列腺素E2(prostaglandin E2,PGE2)水平变化.结果:第1部分实验中,CLP术后小鼠出现明显嗜睡、竖毛、寒颤和厌食等症状,CLP1组和CLP2组小鼠48 h死亡率分别为20％和30％.两部分实验中行小鼠腹腔盲肠结扎穿孔术组小鼠神经行为学评分均显著低于对照组和假手术组(P<0.01);Morris水迷宫中逃避潜伏期时间均显著延长(P<0.01),目标象限停留时间和穿越平台次数减少(P<0.01);悬挂实验和爬杆实验中评分均出现显著降低(P<0.01);在避暗实验开始后大部分小鼠活动量显著减小甚至未曾进入暗室(P<0.05).第2部分实验中,CLP术后小鼠血清中PGE2释放量显著增加(P<0.01).结论:通过12号针行盲肠结扎穿孔术可成功建立稳定的脓毒症相关性脑病小鼠模型,用此法建立的SAE小鼠模型存在学习记忆认知功能障碍.

In this study, we investigated lipopolysaccharide (LPS)-induced cognitive impairment and neuroinflammation in C57BL/6J mice by using behavioral tests, immunofluorescence, enzyme-linked immunosorbent assay (ELISA) and Western blot. We found that LPS treatment leads to sickness behavior and cognitive impairment in mice as shown in the Morris water maze and passive avoidance test, and these effects were accompanied by microglia activation (labeled by ionized calcium binding adaptor molecule-1, IBA-1) and neuronal cell loss (labeled by microtubule-associated protein 2, MAP-2) in the hippocampus. The levels of interleukin-4 (IL-4) and interleukin-10 (IL-10) in the serum and brain homogenates were reduced by the LPS treatment, while the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), prostaglandin E2 (PGE 2 ) and nitric oxide (NO) were increased. In addition, LPS promoted the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in the brain homogenates. The Western blot analysis showed that the nuclear factor kappa B (NF-κB) signaling pathway was activated in the LPS groups. Furthermore, VIPER, which is a TLR-4-specific inhibitory peptide, prevented the LPS-induced neuroinflammation and cognitive impairment. These data suggest that LPS induced cognitive impairment and neuroinflammation via microglia activation by activating the NF-kB signaling pathway; furthermore, we compared the time points, doses, methods and outcomes of LPS administration between intraperitoneal and intracerebroventricular injections of LPS in LPS-induced neuroinflammation and cognitive impairment, and these data may provide additional insight for researchers performing neuroinflammation research.

Oxidative stress is a key factor of and closely implicated in the pathogenesis of Alzheimer’s disease (AD). We herein used tert-butyl hydroperoxide (t-BHP) to induce oxidative stress and mimic oxidative neurotoxicity in vitro. Lycopene is a natural antioxidant that has a strong ability to eliminate free radicals and shows effective protection in some neurodegenerative disease models. However, the effect of lycopene on t-BHP-induced neuronal damage in primary mouse neurons is unknown. This study aimed to investigate the effects of lycopene on t-BHP-induced neuronal damage and the related mechanisms. We found that lycopene pretreatment effectively enhanced the cell viability, improved the neuron morphology, increased the GSH/GSSG level, restored the mitochondrial membrane potential (ΔΨm) and decreased reactive oxygen species generation. Furthermore, lycopene reduced the ratios of Bax:Bcl-2 and cleaved caspase-3:caspase-3 and the level of cytochrome C, increased the levels of synaptophysin (SYP) and postsynaptic density 95 (PSD95) and activated the PI3K/Akt pathway. In conclusion, lycopene attenuated oxidative stress and reduced t-BHP-induced cell apoptosis, and the mechanism is likely related to activation of the PI3K/Akt pathway. Therefore, lycopene is a potential agent for preventing oxidative stress-mediated AD.

A promising intervention for Alzheimer's disease (AD) would ideally target key pathological factors that are involved in AD pathogenesis. Soluble factors produced by engrafted mesenchymal stem cells (MSCs) mediate potential therapeutic effects in AD. However, these therapeutic benefits are largely hampered by the limited paracrine capacity of MSCs. In this study, we used adenovirus-mediated gene transduction of bone marrow MSCs to deliver exogenous proteins into the brain of APPswe/PSEN1dE9 (APP/PS1) mice in the early stage of impairment. We observed that engrafted MSCs carrying exogenous (C-X3-C motif) ligand 1 (CX3CL1) alone reduced the production of the inflammatory cytokine TNF-ɑ and improved synapse-related protein expression but not cognitive function. Transplantation of MSCs carrying CX3CL1 and Wnt3a (CX3CL1-Wnt3a-MSC) significantly attenuated the learning and memory impairment when compared with a control group. The improvement of neurobehavioral functions in APP/PS1 mice treated with CX3CL1-Wnt3a-MSC was related to the inhibition of microglial neurotoxicity and promotion of hippocampal neurogenesis. Transplantation of CX3CL1-Wnt3a-MSC also regulated phosphoinositide 3-kinase/activated protein kinase B (PI3K/AKT) signaling to inhibit the activity of glycogen synthase kinase 3 beta (GSK3β). Taken together, these results indicate that the delivery of exogenous proteins via MSCs can modulate microglial function and enhance neurogenesis, thereby providing new insights into AD intervention.

Objective: To investigate whether phenylephrine (PE) inhibits sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury through the PI3K/Akt signaling pathway. Methods: A rat model of sepsis was established by cecal ligation and puncture. PE and/or wortmannin (a PI3K inhibitor) were administered to investigate the role of PI3K/Akt signaling in mediating the effects of PE on inhibiting sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury. Hematoxylin–eosin staining, echocardiography, and Langendorff system were used to examine the myocardial injury and function. The concentrations of TNF-α and IL-6 were analyzed by enzyme-linked immunosorbent assay. Intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), myeloperoxidase, mitochondria-related fusion/fission proteins, and PI3K/Akt signaling pathway–associated proteins were analyzed by Western blotting. Results: PE improved the cardiac function and survival in septic rats. PE decreased TNF-α, IL-6, ICAM-1, VCAM-1, and myeloperoxidase contents in the myocardium of septic rats. Meanwhile, PE increased the fusion-related proteins and decreased the fission-related proteins in the myocardial mitochondria of septic rats. On the other hand, PE activated the PI3K/Akt signaling pathway in the cecal ligation and puncture–treated rats, and all the protective effects of PE were abolished by wortmannin. Conclusions: PE attenuated sepsis-induced cardiac dysfunction, cardiac inflammation, and mitochondrial injury through the PI3K/Akt signaling pathway.

PYNOD, a nod-like receptors (NLR)-like protein, was indicated to inhibit NF-κB activation, caspase-1-mediated interleukin (IL)-1β release and cell apoptosis in a dose-dependent manner. Exogenous addition of recombinant PYNOD to mixed glial cultures may suppress caspase-1 activation and IL-1β secretion induced by Aβ. However, to the best of our knowledge, there no study has focused on the immunoregulatory effects of PYNOD specifically in microglia. The present study aimed to explore the roles of PYNOD involved in the lipopolysaccharides (LPS)-induced microglial inflammation and consequent neurotoxicity. Murine microglial BV-2 cells were transfected with pEGFP-C2-PYNOD (0-5.0 µg/ml) for 24 h and incubated with or without LPS (1 µg/ml) for a further 24 h. Cell viability was determined using MTT assay and the secretion of nitric oxide (NO), IL-1β and caspase-1 was measured using the Griess method or ELISA. Protein expression levels of NF-κB p65 and inducible nitric oxide synthase (iNOS) were detected by immunofluorescent staining and/or western blot analysis. Co-culture of BV-2 cells with human neuroblastoma cell line SK-N-SH was performed in Transwell plates and the cell viability and apoptosis (using flow cytometry) of SK-N-SH cells were determined. Results indicated that PYNOD overexpression inhibited NO secretion and iNOS protein expression induced by LPS in BV-2 cells, with no detectable cytotoxicity. PYNOD overexpression also reduced the secretion of IL-1β and caspase-1 from BV-2 cells upon LPS stimulation. These effects were dose-dependent. Additionally, PYNOD overexpression prevented LPS-induced nuclear translocation of NF-κB p65 in BV-2 cells. The growth-inhibitory and apoptosis-promoting effects of BV-2 cells towards SK-N-SH cells were alleviated as a result of PYNOD overexpression. In conclusion, PYNOD may mitigate microglial inflammation and consequent neurotoxicity.