PDGF-BB Preserves Mitochondrial Morphology, Attenuates ROS Production, and Upregulates Neuroglobin in an Astrocytic Model Under Rotenone Insult

The differences in cytokine signatures between severe fever with thrombocytopenia syndrome (SFTS) and hemorrhagic fever with renal syndrome (HFRS)

Severe fever with thrombocytopenia syndrome (SFTS) virus and hantavirus are categorized under the Bunyavirales order. The severe disease progression in both SFTS and hemorrhagic fever with renal syndrome (HFRS) is associated with cytokine storms. This study aimed to explore the differences in cytokine profiles and immune responses between the two diseases. A cross-sectional, single-center study involved 100 participants, comprising 46 SFTS patients, 48 HFRS patients, and 6 healthy controls. The study employed the Luminex cytokine detection platform to measure 48 cytokines. The differences in cytokine profiles and immune characteristics between the two diseases were further analyzed using multiple linear regression, principal component analysis, and random forest method. Among the 48 cytokines tested, 30 showed elevated levels in SFTS and/or HFRS compared to the healthy control group. Furthermore, there were 19 cytokines that exhibited significant differences between SFTS and HFRS. Random forest analysis suggested that TRAIL and CTACK were predictive of SFTS, while IL2Ralpha, MIG, IL-8, IFNalpha2, HGF, SCF, MCP-3, and PDGFBB were more common with HFRS. It was further verified by the receiver operating characteristic with area under the curve >0.8 and P-values <0.05, except for TRAIL. Significant differences were observed in the cytokine profiles of SFTS and HFRS, with TRAIL, IL2Ralpha, MIG, and IL-8 being the top 4 cytokines that most clearly distinguished the two diseases.

IMPORTANCE

SFTS and HFRS differ in terms of cytokine immune characteristics. TRAIL, IL-2Ralpha, MIG, and IL-8 were the top 4 that differed markedly between SFTS and HFRS.

Charged Amino Acid Substitutions Affect Conformation of Neuroglobin and Cytochrome c Heme Groups

Neuroglobin (Ngb) is a cytosolic heme protein that plays an important role in protecting cells from apoptosis through interaction with oxidized cytochrome c (Cyt c) released from mitochondria. The interaction of reduced Ngb and oxidized Cyt c is accompanied by electron transfer between them and the reduction in Cyt c. Despite the growing number of studies on Ngb, the mechanism of interaction between Ngb and Cyt c is still unclear. Using Raman spectroscopy, we studied the effect of charged amino acid substitutions in Ngb and Cyt c on the conformation of their hemes. It has been shown that Ngb mutants E60K, K67E, K95E and E60K/E87K demonstrate changed heme conformations with the lower probability of the heme planar conformation compared to wild-type Ngb. Moreover, oxidized Cyt c mutants K25E, K72E and K25E/K72E demonstrate the decrease in the probability of methyl-radicals vibrations, indicating the higher rigidity of the protein microenvironment. It is possible that these changes can affect electron transfer between Ngb and Cyt c.

Factors Affecting the Potential Efficacy of Intrauterine Platelet-Rich Plasma Infusion on Thin Endometrium in Women with Recurrent Implantation Failure

Optimizing endometrial thickness (EMT) is crucial for successful embryo implantation, but enhancing thin endometrium remains a significant challenge. Platelet-rich plasma (PRP)-derived therapies have emerged as a promising approach in reproductive medicine due to their capacity to facilitate tissue repair and regeneration. This study aims to identify the risk factors associated with the failure of intrauterine PRP infusion for thin endometrium in women with recurrent implantation failure (RIF). We retrospectively reviewed data from 77 women with RIF, all exhibiting an EMT of <7 mm. These women underwent programmed hormone therapy for frozen embryo transfer (FET) and received two autologous intrauterine PRP infusions. Following intrauterine PRP-lysate (PL) infusions, the mean increase in EMT was 1.9 ± 1.2 mm, with EMT reaching 7 mm in 86% of the cases (66/77; average EMT, 8.3 mm). We identified an exceedingly thin EMT as a risk factor impacting the therapeutic efficacy in increasing EMT (p = 0.04, OR: 3.16; 95% CI: 1.03-9.67). Additionally, the number of previous uterine surgeries emerged as a prognostic factor for pregnancy failure following PL infusion (p = 0.02, OR: 2.02; 95% CI: 1.12-3.64). Our findings suggest that an extremely thin EMT and a history of numerous uterine surgeries can impede successful pregnancy, even when an optimal EMT is achieved following PRP infusion.

Concordant and Discordant Cerebrospinal Fluid and Plasma Cytokine and Chemokine Responses in Mild Cognitive Impairment and Early-Stage Alzheimer's Disease

Neuroinflammation may be a pathogenic mediator and biomarker of neurodegeneration at the boundary between mild cognitive impairment (MCI) and early-stage Alzheimer's disease (AD). Whether neuroinflammatory processes are endogenous to the central nervous system (CNS) or originate from systemic (peripheral blood) sources could impact strategies for therapeutic intervention. To address this issue, we measured cytokine and chemokine immunoreactivities in simultaneously obtained lumbar puncture cerebrospinal fluid (CSF) and serum samples from 39 patients including 18 with MCI or early AD and 21 normal controls using a 27-plex XMAP bead-based enzyme-linked immunosorbent assay (ELISA). The MCI/AD combined group had significant (p < 0.05 or better) or statistically trend-wise (0.05 ≤ p ≤ 0.10) concordant increases in CSF and serum IL-4, IL-5, IL-9, IL-13, and TNF-α and reductions in GM-CSF, b-FGF, IL-6, IP-10, and MCP-1; CSF-only increases in IFN-y and IL-7 and reductions in VEGF and IL-12p70; serum-only increases in IL-1β, MIP-1α, and eotaxin and reductions in G-CSF, IL-2, IL-8 and IL-15; and discordant CSF-serum responses with reduced CSF and increased serum PDGF-bb, IL-17a, and RANTES. The results demonstrate simultaneously parallel mixed but modestly greater pro-inflammatory compared to anti-inflammatory or neuroprotective responses in CSF and serum. In addition, the findings show evidence that several cytokines and chemokines are selectively altered in MCI/AD CSF, likely corresponding to distinct neuroinflammatory responses unrelated to systemic pathologies. The aggregate results suggest that early management of MCI/AD neuroinflammation should include both anti-inflammatory and pro-neuroprotective strategies to help prevent disease progression.

Molecular Interactions between Neuroglobin and Cytochrome c: Possible Mechanisms of Antiapoptotic Defense in Neuronal Cells

Neuroglobin, which is a heme protein from the globin family that is predominantly expressed in nervous tissue, can promote a neuronal survivor. However, the molecular mechanisms underlying the neuroprotective function of Ngb remain poorly understood to this day. The interactions between neuroglobin and mitochondrial cytochrome c may serve as at least one of the mechanisms of neuroglobin-mediated neuroprotection. Interestingly, neuroglobin and cytochrome c possibly can interact with or without electron transfer both in the cytoplasm and within the mitochondria. This review provides a general picture of molecular interactions between neuroglobin and cytochrome c based on the recent experimental and computational work on neuroglobin and cytochrome c interactions.

PDGFBB improved the biological function of menstrual blood-derived stromal cells and the anti-fibrotic properties of exosomes

BACKGROUND

Intrauterine adhesion (IUA) is a reproductive dysfunction disease characterized by endometrial fibrosis, with limited therapeutic options and poor prognosis. Our previous studies confirmed that menstrual blood-derived stromal cells (MenSCs) effectively attenuated endometrial fibrosis in an animal model of IUA mainly through exosomes. This therapeutic effect can be enhanced by platelet-rich plasma (PRP), in which PDGFBB is an abundant growth factor. Therefore, we aimed to compare the effects of PRP and PDGFBB on the biological activities of MenSCs in vitro, and to further investigate the molecular mechanism of MenSCs-derived exosomes in alleviating endometrial fibrosis.

METHODS

MenSCs were isolated for in vitro functional assays to examine the viability, migration, and stemness of MenSCs. Endometrial stromal cells (EndoSCs) were treated with 50 ug/ml of MenSCs-derived exosomes, obtained by differential ultracentrifugation extraction. The molecular mechanisms by which PDGFBB improves MenSCs and exosomes alleviate EndoSCs fibrosis were then explored using immunofluorescence, western blot, and co-immunoprecipitation.

RESULTS

Both 100 ng/ml PDGFBB and 10% activated PRP promoted the proliferation, increased the S phase of cell cycle, and inhibited apoptosis of MenSCs in vitro. Compared with PRP, PDGFBB significantly promoted MenSCs migration. All of these effects were inhibited by sorafenib, a PDGFR-β inhibitor. PRP and PDGFBB activated AKT/NF-κB signaling pathway in MenSCs and increased the expression of P65 and OCT4. Moreover, pretreatment of PDGFBB did not increase the secretion of MenSCs but significantly increased the anti-fibrosis effects of MenSCs-derived exosomes on IUA-EndoSCs. MenSCs-derived exosomes attenuated SMAD3 phosphorylation and increased YAP ubiquitination, which reduced the binding of YAP/SMAD3. Pretreatment with PDGFBB amplified this effect.

CONCLUSIONS

In summary, PDGFBB could improve the biological functions of MenSCs via AKT/NF-κB signaling pathway, including viability, migration, and stemness. Our results indicated that PDGFBB amplified MenSCs-derived exosomes to attenuate endometrial fibrosis by inhibiting YAP activity, revealing a novel mechanism by which PRP enhanced the ability of MenSCs to repair tissue injury and providing a potential option for improving stem cell efficacy in IUA.

Platelet derived growth factor promotes the recovery of traumatic brain injury by inhibiting endoplasmic reticulum stress and autophagy-mediated pyroptosis

Autophagy and endoplasmic reticulum stress (ER stress) are important in numerous pathological processes in traumatic brain injury (TBI). Growing evidence has indicated that pyroptosis-associated inflammasome is involved in the pathogenesis of TBI. Platelet derived growth factor (PDGF) has been reported to be as a potential therapeutic drug for neurological diseases. However, the roles of PDGF, autophagy and ER stress in pyroptosis have not been elucidated in the TBI. This study investigated the roles of ER stress and autophagy after TBI at different time points. We found that the ER stress and autophagy after TBI were inhibited, and the expressions of pyroptosis-related proteins induced by TBI, including NLRP3, Pro-Caspase1, Caspase1, GSDMD, GSDMD P30, and IL-18, were decreased upon PDGF treatment. Moreover, the rapamycin (RAPA, an autophagy activator) and tunicamycin (TM, an ER stress activator) eliminated the PDGF effect on the pyroptosis after TBI. Interestingly, the sodium 4-phenylbutyrate (4-PBA, an ER stress inhibitor) suppressed autophagy but 3-methyladenine (3-MA, an autophagy inhibitor) not for ER stress. The results revealed that PDGF improved the functional recovery after TBI, and the effects were markedly reversed by TM and RAPA. Taken together, this study provides a new insight that PDGF is a potential therapeutic strategy for enhancing the recovery of TBI.

Insights Into the Role of Platelet-Derived Growth Factors: Implications for Parkinson’s Disease Pathogenesis and Treatment

Parkinson’s disease (PD), the second most common neurodegenerative disease after Alzheimer’s disease, commonly occurs in the elderly population, causing a significant medical and economic burden to the aging society worldwide. At present, there are few effective methods that achieve satisfactory clinical results in the treatment of PD. Platelet-derived growth factors (PDGFs) and platelet-derived growth factor receptors (PDGFRs) are important neurotrophic factors that are expressed in various cell types. Their unique structures allow for specific binding that can effectively regulate vital functions in the nervous system. In this review, we summarized the possible mechanisms by which PDGFs/PDGFRs regulate the occurrence and development of PD by affecting oxidative stress, mitochondrial function, protein folding and aggregation, Ca2+ homeostasis, and cell neuroinflammation. These modes of action mainly depend on the type and distribution of PDGFs in different nerve cells. We also summarized the possible clinical applications and prospects for PDGF in the treatment of PD, especially in genetic treatment. Recent advances have shown that PDGFs have contradictory roles within the central nervous system (CNS). Although they exert neuroprotective effects through multiple pathways, they are also associated with the disruption of the blood–brain barrier (BBB). Our recommendations based on our findings include further investigation of the contradictory neurotrophic and neurotoxic effects of the PDGFs acting on the CNS.

Effect of Platelet-Derived Growth Factor C on Mitochondrial Oxidative Stress Induced by High d-Glucose in Human Aortic Endothelial Cells

Endothelial dysfunction is an early marker for cardiovascular diseases. Hyperglycemia induces endothelial dysfunction, increasing the production of reactive oxygen species. Platelet-derived growth factor C stimulates angiogenesis and revascularization in ischemic tissues of diabetic mice and promotes the migration of progenitors and mature ECs to injury sites; however, the molecular mechanisms of its actions are not described yet. Here, we evaluated the effect of PDGF-C on oxidative stress induced by HG. Human aortic endothelial cells were grown in glucose concentrations ranging from 5 mmol/L to 35 mmol/L for 1 to 24 h. Treatment with 50 ng/mL PDGF-C was done for 1 to 3 h. Cytosolic and mitochondrial ROS were measured by fluorometry, and the expression of antioxidant enzymes was evaluated by Western blot. Nrf2 and Keap1 expression was assessed by real-time PCR. High glucose induced mitochondrial ROS production. PDGF-C diminished the oxidative stress induced by high glucose, increasing SOD2 expression and SOD activity, and modulating the Keap1 expression gene. These results give new evidence about the mitochondrial antioxidant effect that PDGF-C could exert on endothelial cells exposed to high glucose and its considerable role as a therapeutic target in diabetes.

Neuroglobin, clues to function and mechanism

Neuroglobin is expressed in vertebrate brain and belongs to a branch of the globin family that diverged early in evolution. Sequence conservation and presence in nervous cells of several taxa suggests a relevant role in the nervous system, with tight structural restraints. Twenty years after its discovery, a rich scientific literature provides convincing evidence of the involvement of neuroglobin in sustaining neuron viability in physiological and pathological conditions however, a full and conclusive picture of its specific function, or set of functions is still lacking. The difficulty of unambiguously assigning a precise mechanism and biochemical role to neuroglobin might arise from the participation to one or more cell mechanism that redundantly guarantee the functioning of the highly specialized and metabolically demanding central nervous system of vertebrates. Here we collect findings and hypotheses arising from recent biochemical, biophysical, structural, in cell and in vivo experimental work on neuroglobin, aiming at providing an overview of the most recent literature. Proteins are said to have jobs and hobbies, it is possible that, in the case of neuroglobin, evolution has selected for it more than one job, and support to cover for its occasional failings. Disentangling the mechanisms and roles of neuroglobin is thus a challenging task that might be achieved by considering data from different disciplines and experimental approaches.

Role of Neuroglobin in the Neuroprotective Actions of Estradiol and Estrogenic Compounds

Estradiol exerts neuroprotective actions that are mediated by the regulation of a variety of signaling pathways and homeostatic molecules. Among these is neuroglobin, which is upregulated by estradiol and translocated to the mitochondria to sustain neuronal and glial cell adaptation to injury. In this paper, we will discuss the role of neuroglobin in the neuroprotective mechanisms elicited by estradiol acting on neurons, astrocytes and microglia. We will also consider the role of neuroglobin in the neuroprotective actions of clinically relevant synthetic steroids, such as tibolone. Finally, the possible contribution of the estrogenic regulation of neuroglobin to the generation of sex differences in brain pathology and the potential application of neuroglobin as therapy against neurological diseases will be examined.

Metformin attenuates rotenone-induced oxidative stress and mitochondrial damage via the AKT/Nrf2 pathway

Oxidative stress and mitochondrial dysfunction are now widely accepted as the major factors involved in the pathogenesis of Parkinson's disease (PD). Rotenone, a commonly used environmental toxin also reproduces these principle pathological features of PD. Hence, it is used frequently to induce experimental PD in cells and animals. In this study, we evaluated the neuroprotective effects of metformin against rotenone-induced toxicity in SH-SY5Y cells. Metformin treatment clearly rescued these cells from rotenone-mediated cell death via the reduction of the cytosolic and mitochondrial levels of reactive oxygen species and restoration of mitochondrial function. Furthermore, metformin upregulated PGC-1α, the master regulator of mitochondrial biogenesis and key antioxidant molecules, including glutathione and superoxide dismutase. We demonstrated that the drug exerted its cytoprotective effects by activating nuclear factor erythroid 2-related factor 2 (Nrf2)/heme-oxygenase (HO)-1 pathway, which in turn, is dependent on AKT activation by metformin. Thus, our results implicate that metformin provides neuroprotection against rotenone by inhibiting oxidative stress in the cells by inducing antioxidant system via upregulation of transcription mediated by Nrf2, thereby restoring the rotenone-induced mitochondrial dysfunction and energy deficit in the cells.

Proteomic and Bioinformatic Investigation of Altered Pathways in Neuroglobin-Deficient Breast Cancer Cells

Neuroglobin (NGB) is a myoglobin-like monomeric globin that is involved in several processes, displaying a pivotal redox-dependent protective role in neuronal and extra-neuronal cells. NGB remarkably exerts its function upon upregulation by NGB inducers, such as 17β-estradiol (E2) and H₂O₂. However, the molecular bases of NGB’s functions remain undefined, mainly in non-neuronal cancer cells. Human MCF-7 breast cancer cells with a knocked-out (KO) NGB gene obtained using CRISPR/Cas9 technology were analyzed using shotgun label-free quantitative proteomics in comparison with control cells. The differential proteomics experiments were also performed after treatment with E2, H₂O₂, and E2 + H₂O₂. All the runs acquired using liquid chromatography–tandem mass spectrometry were elaborated within the same MaxQuant analysis, leading to the quantification of 1872 proteins in the global proteomic dataset. Then, a differentially regulated protein dataset was obtained for each specific treatment. After the proteomic study, multiple bioinformatics analyses were performed to highlight unbalanced pathways and processes. Here, we report the proteomic and bioinformatic investigations concerning the effects on cellular processes of NGB deficiency and cell treatments. Globally, the main processes that were affected were related to the response to stress, cytoskeleton dynamics, apoptosis, and mitochondria-driven pathways.

Neonatal Rotenone Administration Induces Psychiatric Disorder-Like Behavior and Changes in Mitochondrial Biogenesis and Synaptic Proteins in Adulthood

Since psychiatric disorders are associated with changes in the development of the nervous system, an energy-dependent mechanism, we investigated whether mitochondrial inhibition during the critical neurodevelopment window in rodents would be able to induce metabolic alterations culminating in psychiatric-like behavior. We treated male Wistar rat puppies (P) with rotenone (Rot), an inhibitor of mitochondrial complex I, from postnatal days 5 to 11 (P5-P11). We demonstrated that at P60 and P120, Rot-treated animals showed hyperlocomotion and deficits in social interaction and aversive contextual memory, features observed in animal models of schizophrenia, autism spectrum disorder, and attention deficit hyperactivity disorder. During adulthood, Rot-treated rodents also presented modifications in CBP and CREB levels in addition to a decrease in mitochondrial biogenesis and Nrf1 expression. Additionally, NFE2L2-activation was not altered in Rot-treated P60 and P120 animals; an upregulation of pNFE2L2/ NFE2L2 was only observed in P12 cortices. Curiously, ATP/ADP levels did not change in all ages evaluated. Rot administration in newborn rodents also promoted modification in Rest and Mecp2 expression, and in synaptic protein levels, named PSD-95, Synaptotagmin-1, and Synaptophysin in the adult rats. Altogether, our data indicate that behavioral abnormalities and changes in synaptic proteins in adulthood induced by neonatal Rot administration might be a result of adjustments in CREB pathways and alterations in mitochondrial biogenesis and Nrf1 expression, rather than a direct deficiency of energy supply, as previously speculated. Consequently, Rot-induced psychiatric-like behavior would be an outcome of alterations in neuronal paths due to mitochondrial deregulation.

Mitochondrial Dysfunction in Astrocytes: A Role in Parkinson's Disease?

Mitochondrial dysfunction is a hallmark of Parkinson’s disease (PD). Astrocytes are the most abundant glial cell type in the brain and are thought to play a pivotal role in the progression of PD. Emerging evidence suggests that many astrocytic functions, including glutamate metabolism, Ca²⁺ signaling, fatty acid metabolism, antioxidant production, and inflammation are dependent on healthy mitochondria. Here, we review how mitochondrial dysfunction impacts astrocytes, highlighting translational gaps and opening new questions for therapeutic development.

The potential of mitochondrial modulation by neuroglobin in treatment of neurological disorders

Neuroglobin is the third member of the globin family to be identified in 2000 in neurons of both human and mouse nervous systems. Neuroglobin is an oxygen-binding globin found in neurons within the central nervous system as well as in peripheral neurons, that produces a protective effect against hypoxic/ischemic damage induced by promoting oxygen availability within the mitochondria. Numerous investigations have demonstrated that impaired neuroglobin functioning is implicated in the pathogenesis of multiple neurodegenerative disorders. Several in vitro and animal studies have reported the potential of neuroglobin upregulation in improving the neuroprotection through modulation of mitochondrial functions, such as ATP production, clearing reactive oxygen species (ROS), promoting the dynamics of mitochondria, and controlling apoptosis. Neuroglobin acts as a stress-inducible globin, which has been associated hypoxic/ischemic insults where it acts to protect the heart and brain, providing a wide range of applicability in the treatment of human disorders. This review article discusses normal physiological functions of neuroglobin in mitochondria-associated pathways, as well as outlining how dysregulation of neuroglobin is associated with the pathogenesis of neurodegenerative disorders.

S-methyl-L-cysteine Protects against Antimycin A-induced Mitochondrial Dysfunction in Neural Cells via Mimicking Endogenous Methionine-centered Redox Cycle

Mitochondrial superoxide overproduction is believed to be responsible for the neurotoxicity associated with neurodegeneration. Mitochondria-targeted antioxidants, such as MitoQ, have emerged as potentially effective antioxidant therapies. Methionine sulfoxide reductase A (MsrA) is a key mitochondrial-localized endogenous antioxidative enzyme and it can scavenge oxidizing species by catalyzing the methionine (Met)-centered redox cycle (MCRC). In this study, we observed that the natural L-Met acted as a good scavenger for antimycin A-induced mitochondrial superoxide overproduction in PC12 cells. This antioxidation was largely dependent on the Met oxidase activity of MsrA. S-methyl-L-cysteine (SMLC), a natural analogue of Met that is abundantly found in garlic and cabbage, could activate the Met oxidase activity of MsrA to scavenge free radicals. Furthermore, SMLC protected against antimycin A-induced mitochondrial membrane depolarization and alleviated 1-methyl-4-phenylpyridinium (MPP⁺)-induced neurotoxicity. Thus, our data highlighted the possibility for SMLC supplement in the detoxication of mitochondrial damage by activating the Met oxidase activity of MsrA.

Biological responses induced by high molecular weight chitosan administrated jointly with Platelet-derived Growth Factors in different mammalian cell lines

In this work, we studied cellular responses known to be involved in tissue regeneration, such as proliferation, migration and tubulogenesis under High Molecular Weight Chitosan (HMWC) and recombinant Platelet-derived Growth Factor (PDGF) treatments using an in vitro cell culture approach. We also analysed changes in mitochondrial dynamics that could be associated with such biological responses. For this proposes, endothelial human cell lines (EA.hy926 and ECFC) and 3T3-L1 mouse fibroblasts were used. The intracellular uptake of HMWC and their co-localization with acidic compartments were evaluated. Our results show that HMWC enhance PDGF-induced proliferation and cell migration in 3T3-L1 fibroblasts. An increase in PDGF-induced mitochondrial fragmentation was observed in 3T3-L1 cell line, but not in EA.hy926 cells, after the addition of HMWC. Endothelial cells, EA.hy926 and ECFC, potentiate their tubulogenesis capacity with the only addition of HMWC. The HMWC/PDGF-BB treatment notably enhanced tubule formation showing a synergistic effect when act combined in cell culture medium. The knowledge of these cellular responses can be used to design new tissue repair strategies using HMWC and PDGF.

The cytokine profile of follicular fluid changes during ovarian ageing

OBJECTIVE

Ovarian ageing is one of the commonest causes of infertility in patients consulting for assisted reproductive technology. The composition of the follicular fluid (FF), which reflects the exchanges between the oocyte and its microenvironment, has been extensively investigated to determine the metabolic pathways involved in various ovarian disorders. Considering the importance of cytokines in folliculogenesis, we focused on the cytokine profile of the FF during ovarian ageing.

MATERIAL AND METHODS

Our cross-sectional study assesses the levels of 27 cytokines and growth factors in the FF of two groups of women undergoing in vitro fertilization. One group included 28 patients with ovarian ageing clinically characterized by a diminished ovarian reserve (DOR), and the other group included 29 patients with a normal ovarian reserve (NOR), serving as controls.

RESULTS

With univariate analysis, the cytokine profile was found to differ significantly between the two groups. After adjustment of the p-values, platelet-derived growth factor-BB (PDGF-BB) was the only cytokine with a significantly lower concentration in the DOR group (7.34 ± 16.11 pg/mL) than in the NOR group (24.39 ± 41.38 pg/mL) (p = 0.005), independently of chronological age.

CONCLUSION

Thus, PDGF-BB would seem to be implicated in the physiopathology of DOR, potentially in relation to its role in folliculogenesis or in the protection against oxidative stress.

Balanced single-vector co-delivery of VEGF/PDGF-BB improves functional collateralization in chronic cerebral ischemia

The myoblast-mediated delivery of angiogenic genes represents a cell-based approach for targeted induction of therapeutic collateralization. Here, we tested the superiority of myoblast-mediated co-delivery of vascular endothelial growth factor-A (VEGF) together with platelet-derived growth factor-BB (PDGF-BB) on transpial collateralization of an indirect encephalomyosynangiosis (EMS) in a model of chronic cerebral ischemia. Mouse myoblasts expressing a reporter gene alone (empty vector), VEGF, PDGF-BB or VEGF and PDGF-BB through a single bi-cistronic vector (VIP) were implanted into the temporalis muscle of an EMS following permanent ipsilateral internal carotid artery occlusion in adult, male C57BL/6N mice. Over 84 days, myoblast engraftment and gene product expression, hemodynamic impairment, transpial collateralization, angiogenesis, pericyte recruitment and post-ischemic neuroprotection were assessed. By day 42, animals that received PDGF-BB in combination with VEGF (VIP) showed superior hemodynamic recovery, EMS collateralization and ischemic protection with improved pericyte recruitment around the parenchymal vessels and EMS collaterals. Also, supplementation of PDGF-BB resulted in a striking astrocytic activation with intrinsic VEGF mobilization in the cortex below the EMS. Our findings suggest that EMS surgery together with myoblast-mediated co-delivery of VEGF/PDGF-BB may have the potential to serve as a novel treatment strategy for augmentation of collateral flow in the chronically hypoperfused brain.

Multiple Pathways Involved in Palmitic Acid-Induced Toxicity: A System Biology Approach

Inflammation is a complex biological response to injuries, metabolic disorders or infections. In the brain, astrocytes play an important role in the inflammatory processes during neurodegenerative diseases. Recent studies have shown that the increase of free saturated fatty acids such as palmitic acid produces a metabolic inflammatory response in astrocytes generally associated with damaging mechanisms such as oxidative stress, endoplasmic reticulum stress, and autophagic defects. In this aspect, the synthetic neurosteroid tibolone has shown to exert protective functions against inflammation in neuronal experimental models without the tumorigenic effects exerted by sexual hormones such as estradiol and progesterone. However, there is little information regarding the specific mechanisms of tibolone in astrocytes during inflammatory insults. In the present study, we performed a genome-scale metabolic reconstruction of astrocytes that was used to study astrocytic response during an inflammatory insult by palmitate through Flux Balance Analysis methods and data mining. In this aspect, we assessed the metabolic fluxes of human astrocytes under three different scenarios: healthy (normal conditions), induced inflammation by palmitate, and tibolone treatment under palmitate inflammation. Our results suggest that tibolone reduces the L-glutamate-mediated neurotoxicity in astrocytes through the modulation of several metabolic pathways involved in glutamate uptake. We also identified a set of reactions associated with the protective effects of tibolone, including the upregulation of taurine metabolism, gluconeogenesis, cPPAR and the modulation of calcium signaling pathways. In conclusion, the different scenarios studied in our model allowed us to identify several metabolic fluxes perturbed under an inflammatory response and the protective mechanisms exerted by tibolone.

Overview of Crosstalk Between Multiple Factor of Transcytosis in Blood Brain Barrier

Blood brain barrier (BBB) conserves unique regulatory system to maintain barrier tightness while allowing adequate transport between neurovascular units. This mechanism possess a challenge for drug delivery, while abnormality may result in pathogenesis. Communication between vascular and neural system is mediated through paracellular and transcellular (transcytosis) pathway. Transcytosis itself showed dependency with various components, focusing on caveolae-mediated. Among several factors, intense communication between endothelial cells, pericytes, and astrocytes is the key for a normal development. Regulatory signaling pathway such as VEGF, Notch, S1P, PDGFβ, Ang/Tie, and TGF-β showed interaction with the transcytosis steps. Recent discoveries showed exploration of various factors which has been proven to interact with one of the process of transcytosis, either endocytosis, endosomal rearrangement, or exocytosis. As well as providing a hypothetical regulatory pathway between each factors, specifically miRNA, mechanical stress, various cytokines, physicochemical, basement membrane and junctions remodeling, and crosstalk between developmental regulatory pathways. Finally, various hypotheses and probable crosstalk between each factors will be expressed, to point out relevant research application (Drug therapy design and BBB-on-a-chip) and unexplored terrain.

Effects of curcumin on mitochondria in neurodegenerative diseases

Neurodegenerative diseases (NDs) result from progressive deterioration of selectively susceptible neuron populations in different central nervous system (CNS) regions. NDs are classified in accordance with the primary clinical manifestations (e.g., parkinsonism, dementia, or motor neuron disease), the anatomic basis of neurodegeneration (e.g., frontotemporal degenerations, extrapyramidal disorders, or spinocerebellar degenerations), and fundamental molecular abnormalities (e.g., mutations, mitochondrial dysfunction, and its related molecular alterations). NDs include the Alzheimer disease and Parkinson disease, among others. There is a growing evidence that mitochondrial dysfunction and its related mutations in the form of oxidative/nitrosative stress and neurotoxic compounds play major roles in the pathogenesis of various NDs. Curcumin, a polyphenol and nontoxic compound, obtained from turmeric, has been shown to have a therapeutic beneficial effect in various disorders especially on the CNS cells. It has been shown that curcumin has considerable neuro- and mitochondria-protective properties against broad-spectrum neurotoxic compounds and diseases/injury-associating NDs. In this article, we have reviewed the various effects of curcumin on mitochondrial dysfunction in NDs.

Mn-TAT PTD-Ngb attenuates oxidative injury by an enhanced ROS scavenging ability and the regulation of redox signaling pathway

Neurological diseases have a close relationship to excessive reactive oxygen species (ROS). Neuroglobin (Ngb), an intrinsic protective factor, protected cells from hypoxic/ischemic injury. In the present, we reported a novel neuroprotective manganese porphyrin reconstituted metal protein, Mn-TAT PTD-Ngb, consisting of a HIV Tat protein transduction domain sequence (TAT PTD) attached to the N-terminal of apo-Ngb. Mn-TAT PTD-Ngb had a stronger ROS scavenging ability than that of TAT PTD-Ngb, and reduced intracellular ROS production and restored the function of the mitochondria and inhibited the mitochondria-dependent apoptosis. Besides, Mn-TAT PTD-Ngb activated the phosphoinositide-3 kinase (PI3K)/Akt signaling pathway, which up-regulated the expression of nuclear factor E2-related factor 2 (Nrf2), Heme oxygenase-1 (HO-1), superoxide dismutase (SOD), catalase (CAT). The results showed that the redox chemistry of Mn-TAT PTD-Ngb and redox regulation of multiple signaling pathways attenuated the oxidative injury.

Connecting the Dots in the Neuroglobin-Protein Interaction Network of an Unstressed and Ferroptotic Cell Death Neuroblastoma Model

Neuroglobin is a heme protein of which increased levels provide neuroprotection against amyloid proteinopathy and hemorrhagic damage. These cellular stressors involve the promotion of ferroptosis—an iron-dependent, lipid peroxide-accreting form of cell death. Hence, we questioned whether neuroglobin could oppose ferroptosis initiation. We detected human neuroglobin (hNgb)-EGFP-expressing SH-SY5Y cells to be significantly more resistant to ferroptosis induction, identifying 0.68-fold less cell death. To elucidate the underlying pathways, this study investigated hNgb-protein interactions with a Co-IP-MS/MS approach both under a physiological and a ferroptotic condition. hNgb binds to proteins of the cellular iron metabolism (e.g., RPL15 and PCBP3) in an unstressed condition and shows an elevated binding ratio towards cell death-linked proteins, such as HNRNPA3, FAM120A, and ABRAXAS2, under ferroptotic stress. Our data also reveal a constitutive interaction between hNgb and the longevity-associated heterodimer XRCC5/XRCC6. Disentangling the involvement of hNgb and its binding partners in cellular processes, using Ingenuity Pathway Analysis, resulted in the integration of hNgb in the ubiquitination pathway, mTOR signaling, 14-3-3-mediated signaling, and the glycolysis cascade. We also detected a previously unknown strong link with motor neuropathies. Hence, this study contributes to the elucidation of neuroglobin’s involvement in cellular mechanisms that provide neuroprotection and the upkeep of homeostasis.

Amyloid-β25-35 Upregulates Endogenous Neuroprotectant Neuroglobin via NFκB Activation in vitro

Neuroglobin (Ngb) has been reported to be increased in early and moderately advanced Alzheimer's disease (AD) stages but declined in the severe stage. However, its regulatory mechanisms and pathophysiological roles in the disease remain to be defined. In this study, we found that Ngb expression was significantly upregulated by low dose Aβ25-35, the neurotoxic fragment of Aβ1 - 40 and Aβ1 - 42, but was not further increased by a higher dose of Aβ25-35. Mutation analysis and supershift assay demonstrated that transcription factor Nuclear Factor κB (NFκB), κB2 and κB3 sites located in mouse Ngb promoter region were involved in dynamic regulation of Ngb expression in response to different doses of Aβ25-35 stimulation. In addition, we found that suppression of endogenous Ngb expression exacerbated Aβ25-35-induced neuronal cell death and mitochondrial dysfunction. Our results indicate that endogenous Ngb expression may be upregulated by low dose Aβ25-35, which is responsible for protecting against Aβ25-35-mediated neurotoxicity. These experimental findings suggest that upregulation of endogenous Ngb expression might be an effective intervention approach for AD.

Crosstalk between soluble PDGF-BB and PDGFRβ promotes astrocytic activation and synaptic recovery in the hippocampus after subarachnoid hemorrhage

Platelet-derived growth factor receptor β (PDGFRβ) dynamically changes after brain injury, possibly mediating the neuroprotective role of soluble homodimers of the platelet-derived growth factor β subunit (PDGF-BB) that is secreted by microcirculation cells. The aim of this study was to determine whether binding of PDGF-BB to astrocytic PDGFRβ enhanced crosstalk among the various components of the neurovascular unit, leading to synaptic recovery after subarachnoid hemorrhage (SAH). The soluble PDGF-BB from the cerebrospinal fluid (CSF) of patients with SAH was measured. The relationship between PDGF-BB treatment and astrocytic PDGFRβ signaling was further explored in vivo and in vitro in experimental SAH models. Compared with the levels in the control samples, the PDGF-BB protein levels in the CSF of patients with SAH were significantly increased. After the generation of experimental SAH, astrocyte activation markers were markedly induced by the binding of PDGF-BB to astrocytic PDGFRβ, accompanied by improved levels of synaptic recovery and cognitive function. Soluble PDGF-BB and astrocytic PDGFRβ signaling are essential for the neuroprotective effect in the hippocampus and the coculture system in vitro after SAH that otherwise leads to cognitive dysfunction and neuronal damage.-Zhou, X., Wu, Q., Lu, Y., Zhang, X., Lv, S., Shao, J., Zhou, Y., Chen, J., Hou, L., Huang, C., Zhang, X. Crosstalk between soluble PDGF-BB and PDGFRβ promotes astrocytic activation and synaptic recovery in the hippocampus after subarachnoid hemorrhage.

Mitochondrial Neuroglobin Is Necessary for Protection Induced by Conditioned Medium from Human Adipose-Derived Mesenchymal Stem Cells in Astrocytic Cells Subjected to Scratch and Metabolic Injury

Astrocytes are specialized cells capable of regulating inflammatory responses in neurodegenerative diseases or traumatic brain injury. In addition to playing an important role in neuroinflammation, these cells regulate essential functions for the preservation of brain tissue. Therefore, the search for therapeutic alternatives to preserve these cells and maintain their functions contributes in some way to counteract the progress of the injury and maintain neuronal survival in various brain pathologies. Among these strategies, the conditioned medium from human adipose-derived mesenchymal stem cells (CM-hMSCA) has been reported with a potential beneficial effect against several neuropathologies. In this study, we evaluated the potential effect of CM-hMSCA in a model of human astrocytes (T98G cells) subjected to scratch injury. Our findings demonstrated that CM-hMSCA regulates the cytokines IL-2, IL-6, IL-8, IL-10, GM-CSF, and TNF-α, downregulates calcium at the cytoplasmic level, and regulates mitochondrial dynamics and the respiratory chain. These actions are accompanied by modulation of the expression of different proteins involved in signaling pathways such as AKT/pAKT and ERK1/2/pERK, and may mediate the localization of neuroglobin (Ngb) at the cellular level. We also confirmed that Ngb mediated the protective effects of CM-hMSCA through regulation of proteins involved in survival pathways and oxidative stress. In conclusion, regulation of brain inflammation combined with the recovery of fundamental cellular aspects in the face of injury makes CM-hMSCA a promising candidate for the protection of astrocytes in brain pathologies.

Role of GTPases in the Regulation of Mitochondrial Dynamics in Alzheimer's Disease and CNS-Related Disorders

Data obtained from several studies have shown that mitochondria are involved and play a central role in the progression of several distinct pathological conditions. Morphological alterations and disruptions on the functionality of mitochondria may be related to metabolic and energy deficiency in neurons in a neurodegenerative disorder. Several recent studies demonstrate the linkage between neurodegeneration and mitochondrial dynamics in the spectrum of a promising era called precision mitochondrial medicine. In this review paper, an analysis of the correlation between mitochondria, Alzheimer's disease, and other central nervous system (CNS)-related disorders like the Parkinson's disease and the autism spectrum disorder is under discussion. The role of GTPases like the mfn1, mfn2, opa1, and dlp1 in mitochondrial fission and fusion is also under investigation, influencing mitochondrial population and leading to oxidative stress and neuronal damage.

Growth Factors and Neuroglobin in Astrocyte Protection Against Neurodegeneration and Oxidative Stress

Neurodegenerative diseases, such as Parkinson and Alzheimer, are among the main public health issues in the world due to their effects on life quality and high mortality rates. Although neuronal death is the main cause of disruption in the central nervous system (CNS) elicited by these pathologies, other cells such as astrocytes are also affected. There is no treatment for preventing the cellular death during neurodegenerative processes, and current drug therapy is focused on decreasing the associated motor symptoms. For these reasons, it has been necessary to seek new therapeutical procedures, including the use of growth factors to reduce α-synuclein toxicity and misfolding in order to recover neuronal cells and astrocytes. Additionally, it has been shown that some growth factors are able to reduce the overproduction of reactive oxygen species (ROS), which are associated with neuronal death through activation of antioxidative enzymes such as catalase, superoxide dismutase, glutathione peroxidase, and neuroglobin. In the present review, we discuss the use of growth factors such as PDGF-BB, VEGF, BDNF, and the antioxidative enzyme neuroglobin in the protection of astrocytes and neurons during the development of neurodegenerative diseases.

Protective Effects of Curcumin Against Ischemia-Reperfusion Injury in the Nervous System

Ischemia-reperfusion injury (I/R injury) is a common feature of ischemic stroke which occurs when blood supply is restored after a period of ischemia. Although stroke is an important cause of death in the world, effective therapeutic strategies aiming at improving neurological outcomes in this disease are lacking. Various studies have suggested the involvement of different mechanisms in the pathogenesis of I/R injury in the nervous system. These mechanisms include oxidative stress, platelet adhesion and aggregation, leukocyte infiltration, complement activation, blood-brain barrier (BBB) disruption, and mitochondria-mediated mechanisms. Curcumin, an active ingredient of turmeric, can affect all these pathways and exert neuroprotective activity culminating in the amelioration of I/R injury in the nervous system. In this review, we discuss the protective effects of curcumin against I/R injury in the nervous system and highlight the studies that have linked biological functions of curcumin and I/R injury improvement.