The Interleukin-10 Family of Cytokines and Their Role in the CNS

Nicotinic regulation of microglia: potential contributions to addiction

Clinical and preclinical studies have identified immunosuppressive effects of nicotine, with potential implications for treating nicotine addiction. Here we review how nicotine can regulate microglia, the resident macrophages in the brain, and corresponding effects of nicotine on neuroimmune signaling. There is significant evidence that activation of α7 nicotinic acetylcholine receptors (nAChRs) on microglia can trigger an anti-inflammatory cascade that alters microglial polarization and activity, cytokine release, and intracellular calcium concentrations, leading to neuroprotection. These anti-inflammatory effects of nicotine-dependent α7 nAChR signaling are lost during withdrawal, suggesting that neuroimmune signaling is potentiated during abstinence, and thus, heightened microglial activity may drive circuit disruption that contributes to withdrawal symptoms and hyperkatifeia. In sum, the clinical literature has highlighted immunomodulatory effects of nicotine and the potential for anti-inflammatory compounds to treat addiction. The preclinical literature investigating the underlying mechanisms points to a role of microglial engagement in the circuit dysregulation and behavioral changes that occur during nicotine addiction and withdrawal, driven, at least in part, by activation of α7 nAChRs on microglia. Specifically targeting microglial signaling may help alleviate withdrawal symptoms in people with nicotine dependence and help to promote abstinence.

Urban indoor gardening enhances immune regulation and diversifies skin microbiota - A placebo-controlled double-blinded intervention study

According to the hygiene and biodiversity hypotheses, frequent exposure to environmental microbiota, especially through soil contact, diversifies commensal microbiota, enhances immune modulation, and ultimately lowers the risk of immune-mediated diseases. Here we test the underlying assumption of the hygiene and biodiversity hypotheses by instructing volunteers to grow edible plants indoors during the winter season when natural exposure to environmental microbiota is low. The one-month randomized, placebo-controlled double-blind trial consisted of two treatments: participants received either microbially diverse growing medium or visually similar but microbially poor growing medium. Skin microbiota and a panel of seven immune markers were analyzed in the beginning of the trial and after one month. The diversity of five bacterial phyla (Bacteroidetes, Planctomycetes, Proteobacteria, Cyanobacteria, and Verrucomicrobia) and one class (Bacteroidia) increased on the skin of participants in the intervention group while no changes were observed in the placebo group. The number of nodes and edges in the co-occurrence networks of the skin bacteria increased on average three times more in the intervention group than in the placebo group. The plasma levels of the immunomodulatory cytokine interleukin 10 (IL-10) increased in the intervention group when compared with the placebo group. A similar trend was observed in the interleukin 17A (IL-17A) levels and in the IL-10:IL-17A ratios. Participants in both groups reported high satisfaction and adherence to the trial. The current study provides evidence in support of the core assumption of the hygiene and biodiversity hypotheses of immune-mediated diseases. Indoor urban gardening offers a meaningful and convenient approach for increasing year-round exposure to environmental microbiota, paving the way for other prophylactic practices that might help prevent immune-mediated diseases.

Effects of Interleukin-19 overexpression in the medial prefrontal cortex on anxiety-related behaviors, BDNF expression and p38/JNK/ERK pathways

Anxiety is a prevalent mental illness known for its high incidence, comorbidity, and tendency to recur, posing significant societal and individual burdens. Studies have highlighted Interleukin-19 (IL-19) as having potential relevance in neuropsychiatric disorders. Our previous research revealed that IL-19 overexpression in colonies exacerbated anxiety-related behaviors induced by dextran sodium sulfate/stress. However, the precise role and molecular mechanisms of IL-19 in anxiety regulation remain uncertain. In this study, we initiated an acute restraint stress (ARS)-induced anxious mouse model and identified heightened expression of IL-19 and IL-20Rα in the medial prefrontal cortex (mPFC) of ARS mice. Notably, IL-19 and IL-20Rα were predominantly present in the excitatory pyramidal neurons of the mPFC under both basal and ARS conditions. Utilizing the adeno-associated virus (AAV) strategy, we demonstrated that IL-19 overexpression in the mPFC induced anxiety-related behaviors and elevated stress susceptibility. Additionally, we observed decreased protein levels of brain-derived neurotrophic factor (BDNF) and postsynaptic density protein 95 (PSD95) in the mPFC of IL-19 overexpression mice, accompanied by reduced phosphorylation of in the p38, JNK, and Erk signaling pathways. These findings emphasize the role of IL-19 in modulating anxiety-related behaviors within the mPFC and suggest its potential as a pathological gene and therapeutic target for anxiety.

Behavioral and inflammatory changes in rats induced by a three-hit stress model: Implications for psychiatric disorders

Many aspects of the impact of childhood trauma remain unknown, such as the age at which individuals are most vulnerable to trauma, whether traumatic experiences have more severe and lasting effects when experienced early in life, and whether early life trauma causes psychiatric conditions such as anxiety and major depressive disorder (MDD) that persist over time or evolve into other disorders. Thus, this study aimed to investigate the impact of traumatic experiences in childhood on susceptibility to mood disorders in adulthood, particularly MDD. Animal models were used to address these questions, and different stressor protocols at various stages of the offspring's life were used. Three-hit starting with injections of Poly: IC was performed on the 9th day of gestation and then considered the first stressor. After birth, the animals were exposed to the maternal deprivation (MD) protocol, which separated the pups from the mother 3 h a day during the first ten days of life. From the 60th day of life, the animals were divided to receive the chronic mild stress (CMS) protocol over 21 days. The stressors can induce anxiety-like behaviors, such as increased locomotor activity through a maternal immune activation protocol using Poly: IC and demonstrating depressive-like behaviors through the MD and CMS protocols. It also showed changes in brain structures for pro-inflammatory parameters, IL-1β and TNF-α, and alterations in anti-inflammatory parameters, IL-4 and IL-10, at different ages of life. The study also found that regulating pro- and anti-inflammatory cytokines is necessary for appropriate neuronal behavior, and stress responses can be both friendly and enemy, with costs and benefits balanced to provide the best-fit result. In conclusion, phenotypic characteristics of animals' life history are shaped by signals transmitted directly or indirectly to developing animals, known as "predictive adaptive responses."

IL-10 protects against OPC ferroptosis by regulating lipid reactive oxygen species levels post stroke

Accumulation of reactive oxygen species (ROS), especially on lipids, induces massive cell death in neurons and oligodendrocyte progenitor cells (OPCs) and causes severe neurologic deficits post stroke. While small compounds, such as deferoxamine, lipostatin-1, and ferrostatin-1, have been shown to be effective in reducing lipid ROS, the mechanisms by which endogenously protective molecules act against lipid ROS accumulation and subsequent cell death are still unclear, especially in OPCs, which are critical for maintaining white matter integrity and improving long-term outcomes after stroke. Here, using mouse primary OPC cultures, we demonstrate that interleukin-10 (IL-10), a cytokine playing roles in reducing neuroinflammation and promoting hematoma clearance, significantly reduced hemorrhage-induced lipid ROS accumulation and subsequent ferroptosis in OPCs. Mechanistically, IL-10 activated the IL-10R/STAT3 signaling pathway and upregulated the DLK1/AMPK/ACC axis. Subsequently, IL-10 reprogrammed lipid metabolism and reduced lipid ROS accumulation. In addition, in an autologous blood injection intracerebral hemorrhagic stroke (ICH) mouse model, deficiency of the endogenous Il-10, specific knocking out Il10r or Dlk1 in OPCs, or administration of ACC inhibitor was associated with increased OPC cell death, demyelination, axonal sprouting, and the cognitive deficits during the chronic phase of ICH and vice versa. These data suggest that IL-10 protects against OPC loss and white matter injury by reducing lipid ROS, supporting further development of potential clinical applications to benefit patients with stroke and related disorders.

Troxerutin dampened hypothalamic neuroinflammation via microglial IL-22/IL-22R1/IRF3 activation in dihydrotestosterone-induced polycystic ovary syndrome rats

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common reproductive-endocrine condition in premenopausal women. Troxerutin, a common clinical anti-coagulant agent, was shown to work as a strong IL-22 boosting agent counteracting the hyperactivated gonadotrophin releasing hormone (GnRH) neurons and heightened GnRH release, the neuroendocrine origin of PCOS with unknown mechanism in rats. Exploring the off-label use of troxerutin medication for PCOS is thus sorely needed.

METHODS

Serum IL-22 content and hypothalamic IL-22 protein were detected. Inflammatory factor levels in hypothalamo-pituitary were evaluated. Immunofluorescence staining was employed to determine the activation and M1/M2-prone polarization of microglia in arcuate hypothalamus and median eminence. RNA-sequencing and transcriptome analysis were applied to explore the potential driver of microglia M2-polarization in response to IL-22 bolstering effect. The function of microglial IL-22/IL-22R1/IRF3 system was further verified using in vivo knockdown of IL-22R1 and a potent IRF3 inhibitor in BV2 microglial cell lines in vitro.

RESULTS

Troxerutin augmented serum IL-22 content, and its consequent spillover into the hypothalamus led to the direct activation of IL-22R1/IRF3 system on microglia, thereby promoted microglia M2 polarization in arcuate hypothalamus and median eminence, dampened hypothalamic neuroinflammation, inhibited hyperactive GnRH and rescued a breadth of PCOS-like traits in dihydrotestosterone (DHT) rats. The salutary effects of troxerutin treatment on hypothalamic neuroinflammation, microglial M1/2 polarization, GnRH secretion and numerous PCOS-like features were blocked by in vivo knockdown of IL-22R1. Moreover, evidence in vitro illustrated that IL-22 supplement to BV-2 microglia cell lines promoted M2 polarization, overproduction of anti-inflammatory marker and limitation of pro-inflammatory factors, whereas these IL-22 effects were blunted by geldanamycin, a potent IRF3 inhibitor.

CONCLUSION

Here, the present study reported the potential off-label use of troxerutin medication, a common clinical anti-coagulant agent and an endogenous IL-22 enhancer, for multiple purposes in PCOS. The rational underlying the application of troxerutin as a therapeutic choice in PCOS derived from its activity as an IL-22 memetic agent targeting the neuro-endocrine origin of PCOS, and its promotive impact on microglia M2 polarization via activating microglial IL-22R1/IRF3 system in the arcuate hypothalamus and median eminence of DHT female rats.

Spinal interleukin-24 contributes to neuropathic pain after peripheral nerve injury through interleukin-20 receptor2 in mice

Neuroinflammation is critically involved in nerve injury-induced neuropathic pain, characterized by local and systemic increased levels of proinflammatory cytokines. Interleukin-24 (IL-24), a key member of the IL-10 family, has been extensively studied for its therapeutic potential in various diseases, including cancer, autoimmune disorders, and bacterial infections, but whether it is involved in the regulation of neuropathic pain caused by peripheral nerve injury (PNI) has not been well established. In this study, we reported that spared nerve injury (SNI) induced a significant upregulation of IL-24 in fibroblasts, neurons, and oligodendrocyte precursor cells (OPCs, also called NG2-glia) in the affected spinal dorsal horns (SDHs), as well as dorsal root ganglions (DRGs). We also found that tumor necrosis factor α (TNF-α) induced the transcriptional expression of IL-24 in cultured fibroblasts, neurons, and NG2-glia; in addition, astrocytes, microglia, and NG2-glia treated with TNF-α exhibited a prominent increase in interleukin-20 receptor 2 (IL-20R2) expression. Furthermore, we evaluated the ability of IL-24 and IL-20R2 to attenuate pain in preclinical models of neuropathic pain. Intrathecal (i.t.) injection of IL-24 neutralizing antibody or IL-20R2 neutralizing antibody could effectively alleviate mechanical allodynia and thermal hyperalgesia after PNI. Similarly, intrathecal injection of IL-24 siRNA or IL-20R2 siRNA also alleviated mechanical allodynia after SNI. The inhibition of IL-24 reduced SNI-induced proinflammatory cytokine (IL-1β and TNF-α) production and increased anti-inflammatory cytokine (IL-10) production. Meanwhile, the inhibition of IL-20R2 also decreased IL-1β mRNA expression after SNI. Collectively, our findings revealed that IL-24/IL-20R might contribute to neuropathic pain through inflammatory response. Therefore, targeting IL-24 could be a promising strategy for treating neuropathic pain induced by PNI.

Unravelling the role of Sildenafil and SB204741 in suppressing fibrotic potential of peritoneal fibroblasts obtained from PD patients

Introduction: Peritoneal fibrosis (PF) results in technique failure in peritoneal dialysis (PD) patients. Peritoneal fibroblasts are characterized by increase in the ACTA2 gene, responsible for alpha smooth muscle actin (α-SΜΑ), extracellular matrix (ECM) production, and inflammatory cytokines production, which are the are key mediators in the pathogenesis of PF. 5-hydroxytryptamine (5-HT; serotonin) induces ECM synthesis in fibroblasts in a transforming growth factor-beta 1 (TGF-β1) dependent manner. The purpose of our study was to identify the potential mechanism and role of sildenafil and 5HT2B receptor inhibitor (SB204741) combination in attenuating PD-associated peritoneal fibrosis. Methods: Studies were performed to determine the effect of TGF-β1, sildenafil, and SB204741 on human peritoneal fibroblasts (HPFBs) isolated from the parietal peritoneum of patients in long-term PD patients (n = 6) and controls (n = 6). HPFBs were incubated with TGF-β1 (10 ng/mL) for 1 h and later with TGF-β1 (10 ng/mL)/[sildenafil (10 µM) or SB204741 (1 µM)] and their combination for 24 h (post-treatment strategy). In the pre-treatment strategy, HPFBs were pre-treated with sildenafil (10 µM) or SB204741 (1 µM) and a combination of the two for 1 h and later with only TGF-β1 (10 ng/mL) for 24 h. Results: The anti-fibrotic effects of the combination of sildenafil and SB204741 were greater than that of each drug alone. In TGF-β1-stimulated HPFBs, pro-fibrotic genes (COL1A1, COL1A2, ACTA2, CTGF, FN1, and TGFB1) exhibited higher expression than in controls, which are crucial targets of sildenafil and SB204741 against peritoneal fibrosis. The synergistic approach played an anti-fibrotic role by regulating the pro- and anti-fibrotic gene responses as well as inflammatory cytokine responses. The combination treatment significantly attenuated peritoneal fibrosis, as evident by the almost complete amelioration of ACTA2 expression, restoration of anti-fibrotic genes (MMP2/TIMP1), and, at least, by reducing the expression of pro-inflammatory cytokines (IFN-γ, IL-4, IL-17, IL-1β, IL-6, TNF-α, and TGF-β1) along with an increase in IL-10 levels. Discussion: Taken together, the above research evidences that the combination of sildenafil and SB204741 may have therapeutic potential in suppressing peritoneal fibrosis due to peritoneal dialysis.

Cannabidiol improves memory and decreases IL-1β serum levels in rats with lipopolysaccharide-induced inflammation

AIM

Memory improving and anti-inflammatory properties of cannabidiol (CBD) were investigated in an experimental model of lipopolysaccharide (LPS)-induced inflammation.

Mesenchymal stem cells overexpressing interleukin-10 prevent allergic airway inflammation

BACKGROUNDS

Allergic airway inflammation is prevalent worldwide and imposes a considerable burden on both society and affected individuals. This study aimed to investigate the therapeutic advantages of mesenchymal stem cells (MSCs) overexpressed interleukin-10 (IL-10) for the treatment of allergic airway inflammation, as both IL-10 and MSCs possess immunosuppressive properties.

METHODS

Induced pluripotent stem cell (iPSC)-derived MSCs were engineered to overexpress IL-10 via lentiviral transfection (designated as IL-10-MSCs). MSCs and IL-10-MSCs were administered intravenously to mice with allergic inflammation induced by ovalbumin (OVA), and the features of allergic inflammation including inflammatory cell infiltration, Th cells in the lungs, and T helper 2 cell (Th2) cytokine levels in bronchoalveolar lavage fluid (BALF) were examined. MSCs and IL-10-MSCs were co-cultured with CD4+ T cells from patients with allergic rhinitis (AR), and the levels of Th2 cells and corresponding type 2 cytokines were studied. RNA-sequence was performed to further investigate the potential effects of MSCs and IL-10-MSCs on CD4+ T cells.

RESULTS

Stable IL-10-MSCs were established and characterised by high IL-10 expression. IL-10-MSCs significantly reduced inflammatory cell infiltration and epithelial goblet cell numbers in the lung tissues of mice with allergic airway inflammation. Inflammatory cell and cytokine levels in BALF also decreased after the administration of IL-10-MSCs. Moreover, IL-10-MSCs showed a stronger capacity to inhibit the levels of Th2 after co-cultured with CD4+ T cells from patients with AR. Furthermore, we elucidated lower levels of IL-5 and IL-13 in IL-10-MSCs treated CD4+ T cells, and blockade of IL-10 significantly reversed the inhibitory effects of IL-10-MSCs. We also reported the mRNA profiles of CD4+ T cells treated with IL-10-MSCs and MSCs, in which IL-10 played an important role.

CONCLUSION

IL-10-MSCs showed positive effects in the treatment of allergic airway inflammation, providing solid support for the use of genetically engineered MSCs as a potential novel therapy for allergic airway inflammation.

Divergent neuroimmune signatures in the cerebrospinal fluid predict differential gender-specific survival among patients with HIV-associated cryptococcal meningitis

Introduction

Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, particularly among women, despite the currently optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system [brain, spinal cord, and cerebrospinal fluid (CSF)] elicits the local production of cytokines, chemokines, and other biomarkers. However, no consistent diagnostic or prognostic neuroimmune signature is reported to underpin the risk of death or to identify mechanisms to improve treatment and survival. We hypothesized that distinct neuroimmune signatures in the CSF would distinguish survivors from people who died on antifungal treatment and who may benefit from tailored therapy.

Methods

We considered baseline clinical features, CSF cryptococcal fungal burden, and CSF neuroimmune signatures with survival at 18 weeks among 419 consenting adults by "gender" (168 women and 251 men by biological sex defined at birth).

Results

Survival at 18 weeks was significantly lower among women than among men {47% vs. 59%, respectively; hazard ratio (HR) = 1.4 [95% confidence interval (CI), 1.0 to 1.9; p = 0.023]}. Unsupervised principal component analysis (PCA) demonstrated divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, women had lower levels of programmed death ligand 1, Interleukin (IL) (IL-11RA/IL-1F30, and IL-15 (IL-15) than men (all p < 0.028). Female survivors compared with those who died expressed significant elevations in levels of CCL11 and CXCL10 chemokines (both p = 0.001), as well as increased T helper 1, regulatory, and T helper 17 cytokines (all p < 0.041). In contrast, male survivors expressed lower levels of IL-15 and IL-8 compared with men who died (p < 0.044).

Conclusions

Survivors of both genders demonstrated a significant increase in the levels of immune regulatory IL-10. In conclusion, the lower survival among women with CM was accompanied by distinct differential gender-specific neuroimmune signatures. These female and male intragender-specific survival-associated neuroimmune signatures provide potential targets for interventions to advance therapy to improve the low survival among people with HIV-associated CM.

Interleukin-1β and TNF-α are elevated in the amygdala of adult rats prenatally exposed to ethanol

Affective disorders, including anxiety and depression, developed in adult offspring of the mothers who consumed alcohol during pregnancy could be associated with an imbalance in neuroimmune factors in the amygdala (corpus amygdaloideum) resulted in impaired emotional stimulus processing. The aim of this study was to compare the content of cytokines TNF-α, IL-1α, IL-1β, IL-10, and IL-17 in the amygdala of adult female rats exposed to alcohol in utero and control rats. Cytokine levels were evaluated using a multiplex immunoassay system; mRNA expression was investigated using a real-time reverse transcription-polymerase chain reaction (RT-qPCR) assay. Prenatal alcohol exposure led to the increase in the content of TNF-α and IL-1β without significant changes in the mRNA expression level. Our data suggest that ethanol exposure to the fetus during pregnancy can result in long-term alterations in the content of the key neuroinflammatory factors in the amygdala, which in turn can be a risk factor for affective disorders in the adulthood.

Concurrent Brain Subregion Microgliosis in an HLA-II Mouse Model of Group A Streptococcal Skin Infection

The broad range of clinical manifestations and life-threatening infections caused by the Gram-positive bacterium, Streptococcus pyogenes or Group A Streptococcus (GAS), remains a significant concern to public health, with a subset of individuals developing neurological complications. Here, we examined the concurrent neuroimmune effects of subcutaneous GAS infections in an HLA-Class II (HLA) transgenic mouse model of subcutaneous GAS infection. To investigate changes in the skin-brain axis, HLA-DQ8 (DQA1*0301/DQB1*0302) mice (DQ8) were randomly divided into three groups: uninfected controls (No Inf), GAS infected and untreated (No Tx), and GAS infected with a resolution by clindamycin (CLN) treatment (CLN Tx) (10 mg/kg/5 days) and were monitored for 16 days post-infection. While the skin GAS burden was significantly reduced by CLN, the cortical and hippocampal GAS burden in the male DQ8 mice was not significantly reduced with CLN. Immunoreactivity to anti-GAS antibody revealed the presence of GAS bacteria in the vicinity of the neuronal nucleus in the neocortex of both No Tx and CLN Tx male DQ8 mice. GAS infection-mediated cortical cytokine changes were modest; however, compared to No Inf or No Tx groups, a significant increase in IL-2, IL-13, IL-22, and IL-10 levels was observed in CLN Tx females despite the lack of GAS burden. Western blot analysis of cortical and hippocampal homogenates showed significantly higher ionized calcium-binding adaptor-1 (Iba-1, microglia marker) protein levels in No Tx females and males and CLN Tx males compared to the No Inf group. Immunohistochemical analysis showed that Iba-1 immunoreactivity in the hippocampal CA3 and CA1 subregions was significantly higher in the CLN Tx males compared to the No Tx group. Our data support the possibility that the subcutaneous GAS infection communicates to the brain and is characterized by intraneuronal GAS sequestration, brain cytokine changes, Iba-1 protein levels, and concurrent CA3 and CA1 subregion-specific microgliosis, even without bacteremia.

Sustained ameliorative effect of Lactobacillus acidophilus LA85 on dextran sulfate sodium-induced colitis in mice

Ulcerative colitis (UC) is a type of inflammatory bowel disease associated with immune system dysfunction caused by gut dysbiosis. This study aimed to investigate the alleviating effect of Lactobacillus acidophilus LA85 on colitis and its underlying mechanism using mouse models of dextran sulfate sodium (DSS)-induced UC. The UC mouse models were established by treating C57BL/6J male mice with 2.5% (w/v) DSS in drinking water for 7 days. These mice received supplementation with either L. acidophilus LA85 (1 × 109 colony-forming units/day) or 200 µL of sterile water once daily (LA85-treated and UC model mice, respectively). The disease activity index (DAI), colon length, and histological changes in the colons of mice were then analyzed at Day 21, and the effects of L. acidophilus LA85 on the gut microbiota and serum inflammatory cytokines were also investigated. Compared with the UC model mice, L. acidophilus LA85-treated UC mice showed significant reductions in a variety of colitis symptoms, including weight loss, the DAI score, colon shortening, and colon tissue damage. Lactobacillus acidophilus LA85 supplementation also significantly decreased the serum concentrations of tumor necrosis factor α and interleukin-6 while increasing the serum concentration of IL-10. Furthermore, LA85 supplementation improved the diversity and composition of the gut microbiota, both of which had been decreased by DSS. In particular, L. acidophilus LA85-treated UC mice showed higher relative abundances of Akkermansia and Romboutsia than the UC model mice. These results demonstrate that L. acidophilus LA85 can alleviate inflammatory diseases of the intestine, such as inflammatory bowel disease, by regulating immune responses and restoring the gut microbiota. PRACTICAL APPLICATION: Ulcerative colitis is a type of inflammatory bowel disease caused by imbalance of gut microbiota. This study showed that L. acidophilus LA85 can alleviate DSS-induced colitis in mice through regulation of inflammatory cytokines, protection of intestinal barrier, and regulation of specific gut microbiota. L. acidophilus LA85 is a promising probiotic candidate for the treatment of UC.

The role and potential therapeutic targets of astrocytes in central nervous system demyelinating diseases

Astrocytes play vital roles in the central nervous system, contributing significantly to both its normal functioning and pathological conditions. While their involvement in various diseases is increasingly recognized, their exact role in demyelinating lesions remains uncertain. Astrocytes have the potential to influence demyelination positively or negatively. They can produce and release inflammatory molecules that modulate the activation and movement of other immune cells. Moreover, they can aid in the clearance of myelin debris through phagocytosis and facilitate the recruitment and differentiation of oligodendrocyte precursor cells, thereby promoting axonal remyelination. However, excessive or prolonged astrocyte phagocytosis can exacerbate demyelination and lead to neurological impairments. This review provides an overview of the involvement of astrocytes in various demyelinating diseases, emphasizing the underlying mechanisms that contribute to demyelination. Additionally, we discuss the interactions between oligodendrocytes, oligodendrocyte precursor cells and astrocytes as therapeutic options to support myelin regeneration. Furthermore, we explore the role of astrocytes in repairing synaptic dysfunction, which is also a crucial pathological process in these disorders.

Divergent Neuroimmune Signatures in the Cerebrospinal Fluid Predict Differential Gender-Specific Survival Among Patients With HIV-Associated Cryptococcal Meningitis

Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, exceptionally among women with the increased threat of death on current optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system (CNS) prompts a neuroimmune reaction to activate pathogen concomitant factors. However, no consistent diagnostic or prognostic immune-mediated signature is reported to underpin the risk of death or mechanism to improve treatment or survival. We theorized that the distinct neuroimmune cytokine or chemokine signatures in the cerebrospinal fluid (CSF), distinguish survivors from people who died on antifungal treatment, who may benefit from tailored therapy. We considered the baseline clinical disease features, cryptococcal microbiologic factors, and CSF neuroimmune modulated signatures among 419 consenting adults by gender (biological sex assigned at birth) (168 females and 251 males) by 18 weeks of survival on antifungal management. Survival at 18 weeks was inferior among females than males (47% vs. 59%; hazard ratio HR=1.4, 95% CI: 1.0 to 1.9, and p=0.023). Unsupervised principal component analysis (PCA) demonstrated the divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, females displayed lower levels of PD-L1, IL-1RA, and IL-15 than males (all p≤0.028). Female survivors compared with those who died, expressed significant fold elevations in levels of CSF (CCL11 - myeloid and CXCL10 - lymphoid chemokine (in both p=0.001), and CSF Th1, Th2, and Th17 cytokines. In contrast, male survivors expressed distinctly lower levels of CSF IL-15 and IL-8 compared with those who died. Survivors of either gender demonstrated a significant increase in the levels of immune regulatory element, IL-10. In the finale, we classified divergent neuroimmune key signatures in CSF by gender, survival, and intragender-specific survival among people with HIV-associated cryptococcal meningitis. These intragender-specific survival associated-neuroimmune signatures, suggests the discrete role of gender immune regulating mechanisms as the possible targets for interventions to advance therapy to improve survival among people with HIV-associated cryptococcal meningitis.

High CCL2 Levels Detected in CSF of Patients with Pediatric Pseudotumor Cerebri Syndrome

Pseudotumor cerebri (PTC) is a disorder characterized by increased intracranial pressure in the absence of a structural lesion or other identifiable cause. Cytokines, which are involved in the regulation of immune responses and inflammation, have been implicated in the pathogenesis of PTC. In a prospective, cross-sectional study at three centers in Israel, we analyzed cerebrospinal fluid (CSF) samples from 60 children aged 0.5-18 years, including 43 children with a definitive diagnosis of PTC and a control group of 17 children. Levels of IL-4, IL-10, IL-17, CCL2, CCL7, CCL8, CCL13, BDNF, and IFN-γ were measured using ELISA kits. Levels of CCL2 were significantly higher in the PTC group compared to the control group (p < 0.05), with no other significant differences in the measured cytokines between the two groups. The groups did not differ significantly in clinical presentation, imaging, treatment, or ophthalmic findings. Our findings provide preliminary evidence that CCL2 may be involved in the pathogenesis of PTC and may serve a potential target for therapy in PTC.

SAFit2 ameliorates paclitaxel-induced neuropathic pain by reducing spinal gliosis and elevating pro-resolving lipid mediators

BACKGROUND

Chemotherapy-induced neuropathic pain (CIPN) describes a pathological pain state that occurs dose-dependently as a side effect and can limit or even impede an effective cancer therapy. Unfortunately, current treatment possibilities for CIPN are remarkably confined and mostly inadequate as CIPN therapeutics themselves consist of low effectiveness and may induce severe side effects, pointing out CIPN as pathological entity with an emerging need for novel treatment targets. Here, we investigated whether the novel and highly specific FKBP51 inhibitor SAFit2 reduces paclitaxel-induced neuropathic pain.

METHODS

In this study, we used a well-established multiple low-dose paclitaxel model to investigate analgesic and anti-inflammatory properties of SAFit2. For this purpose, the behavior of the mice was recorded over 14 days and the mouse tissue was then analyzed using biochemical methods.

RESULTS

Here, we show that SAFit2 is capable to reduce paclitaxel-induced mechanical hypersensitivity in mice. In addition, we detected that SAFit2 shifts lipid levels in nervous tissue toward an anti-inflammatory and pro-resolving lipid profile that counteracts peripheral sensitization after paclitaxel treatment. Furthermore, SAFit2 reduced the activation of astrocytes and microglia in the spinal cord as well as the levels of pain-mediating chemokines. Its treatment also increased anti-inflammatory cytokines levels in neuronal tissues, ultimately leading to a resolution of neuroinflammation.

CONCLUSIONS

In summary, SAFit2 shows antihyperalgesic properties as it ameliorates paclitaxel-induced neuropathic pain by reducing peripheral sensitization and resolving neuroinflammation. Therefore, we consider SAFit2 as a potential novel drug candidate for the treatment of paclitaxel-induced neuropathic pain.

IL-10 production by granulocytes promotes Staphylococcus aureus craniotomy infection

BACKGROUND

Treatment of brain tumors, epilepsy, or hemodynamic abnormalities requires a craniotomy to access the brain. Nearly 1 million craniotomies are performed in the US annually, which increase to ~ 14 million worldwide and despite prophylaxis, infectious complications after craniotomy range from 1 to 3%. Approximately half are caused by Staphylococcus aureus (S. aureus), which forms a biofilm on the bone flap that is recalcitrant to antibiotics and immune-mediated clearance. However, the mechanisms responsible for the persistence of craniotomy infection remain largely unknown. The current study examined the role of IL-10 in promoting bacterial survival.

METHODS

A mouse model of S. aureus craniotomy infection was used with wild type (WT), IL-10 knockout (KO), and IL-10 conditional KO mice where IL-10 was absent in microglia and monocytes/macrophages (CX3CR1CreIL-10 fl/fl) or neutrophils and granulocytic myeloid-derived suppressor cells (G-MDSCs; Mrp8CreIL-10 fl/fl), the major immune cell populations in the infected brain vs. subcutaneous galea, respectively. Mice were examined at various intervals post-infection to quantify bacterial burden, leukocyte recruitment, and inflammatory mediator production in the brain and galea to assess the role of IL-10 in craniotomy persistence. In addition, the role of G-MDSC-derived IL-10 on neutrophil activity was examined.

RESULTS

Granulocytes (neutrophils and G-MDSCs) were the major producers of IL-10 during craniotomy infection. Bacterial burden was significantly reduced in IL-10 KO mice in the brain and galea at day 14 post-infection compared to WT animals, concomitant with increased CD4+ and γδ T cell recruitment and cytokine/chemokine production, indicative of a heightened proinflammatory response. S. aureus burden was reduced in Mrp8CreIL-10 fl/fl but not CX3CR1CreIL-10 fl/fl mice that was reversed following treatment with exogenous IL-10, suggesting that granulocyte-derived IL-10 was important for promoting S. aureus craniotomy infection. This was likely due, in part, to IL-10 production by G-MDSCs that inhibited neutrophil bactericidal activity and TNF production.

CONCLUSION

Collectively, these findings reveal a novel role for granulocyte-derived IL-10 in suppressing S. aureus clearance during craniotomy infection, which is one mechanism to account for biofilm persistence.

Insights into the Potential Impact of Quetiapine on the Microglial Trajectory and Inflammatory Response in Organotypic Cortical Cultures Derived from Rat Offspring

Atypical antipsychotics currently constitute the first-line medication for schizophrenia, with quetiapine being one of the most commonly prescribed representatives of the group. Along with its specific affinity for multiple receptors, this compound exerts other biological characteristics, among which anti-inflammatory effects are strongly suggested. Simultaneously, published data indicated that inflammation and microglial activation could be diminished by stimulation of the CD200 receptor (CD200R), which takes place by binding to its ligand (CD200) or soluble CD200 fusion protein (CD200Fc). Therefore, in the present study, we sought to evaluate whether quetiapine could affect certain aspects of microglial activity, including the CD200-CD200R and CX3CL1-CX3CR1 axes, which are involved in the regulation of neuron-microglia interactions, as well as the expression of selected markers of the pro- and anti-inflammatory profile of microglia (Cd40, Il-1β, Il-6, Cebpb, Cd206, Arg1, Il-10 and Tgf-β). Concurrently, we examined the impact of quetiapine and CD200Fc on the IL-6 and IL-10 protein levels. The abovementioned aspects were investigated in organotypic cortical cultures (OCCs) prepared from the offspring of control rats (control OCCs) or those subjected to maternal immune activation (MIA OCCs), which is a widely implemented approach to explore schizophrenia-like disturbances in animals. The experiments were performed under basal conditions and after additional exposure to the bacterial endotoxin lipopolysaccharide (LPS), according to the "two-hit" hypothesis of schizophrenia. The results of our research revealed differences between control and MIA OCCs under basal conditions and in response to treatment with LPS in terms of lactate dehydrogenase and nitric oxide release as well as Cd200r, Il-1β, Il-6 and Cd206 expression. The additional stimulation with the bacterial endotoxin resulted in a notable change in the mRNA levels of pro- and anti-inflammatory microglial markers in both types of OCCs. Quetiapine diminished the influence of LPS on Il-1β, Il-6, Cebpb and Arg1 expression in control OCCs as well as on IL-6 and IL-10 levels in MIA OCCs. Moreover, CD200Fc reduced the impact of the bacterial endotoxin on IL-6 production in MIA OCCs. Thus, our results demonstrated that quetiapine, as well as the stimulation of CD200R by CD200Fc, beneficially affected LPS-induced neuroimmunological changes, including microglia-related activation.

Exploring potential impacts of pregnancy-related maternal immune activation and extracellular vesicles on immune alterations observed in autism spectrum disorder

Autism Spectrum Disorder (ASD) is a set of neurodevelopmental disorders usually observed in early life, with impacts on behavioral and social skills. Incidence of ASD has been dramatically increasing worldwide, possibly due to increase in awareness/diagnosis as well as to genetic and environmental triggers. Currently, it is estimated that ∼1% of the world population presents ASD symptoms. In addition to its genetic background, environmental and immune-related factors also influence the ASD etiology. In this context, maternal immune activation (MIA) has recently been suggested as a component potentially involved in ASD development. In addition, extracellular vesicles (EVs) are abundant at the maternal-fetal interface and are actively involved in the immunoregulation required for a healthy pregnancy. Considering that alterations in concentration and content of EVs have also been associated with ASD, this article raises a debate about the potential roles of EVs in the processes surrounding MIA. This represents the major differential of the present review compared to other ASD studies. To support the suggested correlations and hypotheses, findings regarding the roles of EVs during pregnancy and potential influences on ASD are discussed, along with a review and update concerning the participation of infections, cytokine unbalances, overweight and obesity, maternal anti-fetal brain antibodies, maternal fever, gestational diabetes, preeclampsia, labor type and microbiota unbalances in MIA and ASD.

Tumor-Associated Macrophage Subsets: Shaping Polarization and Targeting

The tumor microenvironment (TME) is a critical regulator of tumor growth, progression, and metastasis. Among the innate immune cells recruited to the tumor site, macrophages are the most abundant cell population and are present at all stages of tumor progression. They undergo M1/M2 polarization in response to signals derived from TME. M1 macrophages suppress tumor growth, while their M2 counterparts exert pro-tumoral effects by promoting tumor growth, angiogenesis, metastasis, and resistance to current therapies. Several subsets of the M2 phenotype have been observed, often denoted as M2a, M2b, M2c, and M2d. These are induced by different stimuli and differ in phenotypes as well as functions. In this review, we discuss the key features of each M2 subset, their implications in cancers, and highlight the strategies that are being developed to harness TAMs for cancer treatment.

Interactions between genes altered during cardiotoxicity and neurotoxicity in zebrafish revealed using induced network modules analysis

As the manufacturing and development of new synthetic compounds increase to keep pace with the expanding global demand, adverse health effects due to these compounds are emerging as critical public health concerns. Zebrafish have become a prominent model organism to study toxicology due to their genomic similarity to humans, optical clarity, well-defined developmental stages, short generation time, and cost-effective maintenance. It also provides a shorter time frame for in vivo toxicology evaluation compared to the mammalian experimental systems. Here, we used meta-analysis to examine the alteration in genes during cardiotoxicity and neurotoxicity in zebrafish, caused by chemical exposure of any kind. First, we searched the literature comprehensively for genes that are altered during neurotoxicity and cardiotoxicity followed by meta-analysis using ConsensusPathDB. Since constant communication between the heart and the brain is an important physiological phenomenon, we also analyzed interactions among genes altered simultaneously during cardiotoxicity and neurotoxicity using induced network modules analysis in ConsensusPathDB. We observed inflammation and regeneration as the major pathways involved in cardiotoxicity and neurotoxicity. A large number of intermediate genes and input genes anchored in these pathways are molecular regulators of cell cycle progression and cell death and are implicated in tumor manifestation. We propose potential predictive biomarkers for neurotoxicity and cardiotoxicity and the major pathways potentially implicated in the manifestation of a particular toxicity phenotype.

TMEM106B coding variant is protective and deletion detrimental in a mouse model of tauopathy

TMEM106B is a risk modifier for a growing list of age-associated dementias including Alzheimer’s and frontotemporal dementia, yet its function remains elusive. Two key questions that emerge from past work are whether the conservative T185S coding variant found in the minor haplotype contributes to protection, and whether the presence of TMEM106B is helpful or harmful in the context of disease. Here we address both issues while extending the testbed for study of TMEM106B from models of TDP to tauopathy. We show that TMEM106B deletion accelerates cognitive decline, hindlimb paralysis, neuropathology, and neurodegeneration. TMEM106B deletion also increases transcriptional overlap with human AD, making it a better model of disease than tau alone. In contrast, the coding variant protects against tau-associated cognitive decline, neurodegeneration, and paralysis without affecting tau pathology. Our findings show that the coding variant contributes to neuroprotection and suggest that TMEM106B is a critical safeguard against tau aggregation.

IL-22 Promotes Neural Stem Cell Self-Renewal in the Adult Brain

Mainly known for its role in immune defense and inflammation, interleukin 22 (IL-22) has emerged over the past decade as a cytokine involved in the adaptation of stem/progenitor cell activity for tissue homeostasis and repair. IL-22 is present in the brain, which harbors neural stem cells (NSC) in specific niches of which the ventricular-subventricular zone (V-SVZ) is the most important. In this study, we examined a possible effect of IL-22 on NSC in the adult mouse brain. We demonstrate that the IL-22 receptor is expressed in the V-SVZ, mainly in NSC characterized by their SOX2 expression. Addition of IL-22 to V-VSZ cell cultures resulted in an increase in NSC self-renewal, associated with a shift in NSC division mode towards symmetric proliferative divisions at the expense of differentiative divisions. Conversely, loss of IL-22 in knockout mice led to a decrease in neurosphere yield, suggesting a reduction in the NSC population, which was confirmed by the decrease in cells retaining BrdU labeling in IL-22 knockout mice. Our study supports that IL-22 is involved in the development and/or maintenance of V-VSZ NSC and opens new avenues to further investigate the role of IL-22 in NSC biology in health and disease.

Restoration of Motor Function through Delayed Intraspinal Delivery of Human IL-10-Encoding Nucleoside-Modified mRNA after Spinal Cord Injury

Efficient in vivo delivery of anti-inflammatory proteins to modulate the microenvironment of an injured spinal cord and promote neuroprotection and functional recovery is a great challenge. Nucleoside-modified messenger RNA (mRNA) has become a promising new modality that can be utilized for the safe and efficient delivery of therapeutic proteins. Here, we used lipid nanoparticle (LNP)-encapsulated human interleukin-10 (hIL-10)-encoding nucleoside-modified mRNA to induce neuroprotection and functional recovery following rat spinal cord contusion injury. Intralesional administration of hIL-10 mRNA-LNP to rats led to a remarkable reduction of the microglia/macrophage reaction in the injured spinal segment and induced significant functional recovery compared to controls. Furthermore, hIL-10 mRNA treatment induced increased expression in tissue inhibitor of matrix metalloproteinase 1 and ciliary neurotrophic factor levels in the affected spinal segment indicating a time-delayed secondary effect of IL-10 5 d after injection. Our results suggest that treatment with nucleoside-modified mRNAs encoding neuroprotective factors is an effective strategy for spinal cord injury repair.

Role of interleukin-6 and interleukin-10 in morphological and functional changes of the blood-brain barrier in hypertriglyceridemia

BACKGROUND

Hypertriglyceridemia is closely linked to atherosclerosis related inflammatory processes and blood-brain barrier (BBB) dysfunction. Using apolipoprotein B-100 (APOB-100) transgenic mice, an animal model of chronic hypertriglyceridemia, we analyzed BBB function and morphology in vitro and ex vivo. Our objective was to determine which BBB characteristics are produced mainly by interleukin (IL)-6, an atherosclerosis promoting cytokine, and whether these actions can be antagonized by IL-10, an anti-inflammatory cytokine.

METHODS

Brain endothelial and glial cell cultures and brain microvessels were isolated from wild type (WT) and APOB-100 transgenic mice and were treated with IL-6, IL-10 and their combination. First, IL-6 and IL-10 production was measured in WT and APOB-100 microvessels using qPCR. Then functional parameters of endothelial cell cultures were analyzed and immunocytochemistry for key BBB proteins was performed.

RESULTS

IL-6 mRNA levels were higher in brain microvessels than in brain parenchyma of APOB-100 transgenic mice. Transendothelial electric resistance and P-glycoprotein activity were lower, and paracellular permeability was higher in cultured APOB-100 brain endothelial cells. These features were sensitive to both IL-6 and IL-10 treatments. A decreased P-glycoprotein immunostaining was measured in transgenic endothelial cells under control conditions and in WT cells after treating them with IL-6. This effect was antagonized by IL-10. Changes in immunostaining for tight junction proteins were observed after IL-6 exposure, which were in part antagonized by IL-10. In glial cell cultures an increase in aquaporin-4 immunolabeling in the transgenic group and an increase in microglia cell density in WT glia cultures was detected after IL-6 treatment, which was antagonized by IL-10. In isolated brain microvessels a decrease in P-glycoprotein immunolabeled area fraction was measured in APOB-100 microvessels under control conditions and in WT microvessels after every cytokine treatment. ZO-1 immunolabeling showed characteristics similar to that of P-glycoprotein. No change was seen in claudin-5 and occludin immunoreactive area fractions in microvessels. A decrease in aquaporin-4 immunoreactivity was measured in WT microvessels treated by IL-6, which was antagonized by IL-10.

CONCLUSION

IL-6 produced in microvessels contributes to BBB impairment observed in the APOB-100 mice. We showed that IL-10 partly antagonizes the effects of IL-6 at the BBB.

Butyrate promotes post-stroke outcomes in aged mice via interleukin-22

Aging increases the risk of stroke, may exacerbate neuroinflammatory responses, reduce angiogenesis, and promote white matter damage post-stroke, all of which contribute to long-term functional recovery. Butyric acid, an important gut microbial metabolite, showed the highest correlation with the outcomes of ischemic stroke, and butyrate was selected as an effective treatment for aged stroke mice. Here, we tested the neurorestorative effect and potential therapeutic mechanisms of butyrate in aged mice with stroke. Aged male C57BL/6 J mice (17-19 months) were subjected to photothrombotic stroke. We performed butyrate supplementation in the drinking water for 3 weeks before surgery until 14 days after the stroke. At 14 days after ischemic stroke, white matter damage, leukocyte infiltration, and blood-brain barrier permeability were all decreased in the aged stroke mice that received the butyrate treatment, which also improved neurological outcomes by stimulating angiogenesis. Stroke reduces the level of interleukin-22 (IL-22) and butyrate treatment significantly enhanced IL-22 expression in the brain. To further validate the mechanisms of butyrate promoting neurological function after stroke, monoclonal antibodies were used to block IL-22 in aged stroke mice when butyrate treatment was provided. Blocking IL-22 in butyrate-treated aged stroke fails to improve functional outcomes and attenuated butyrate-induced angiogenesis, increased axon/white matter density and blood-brain barrier (BBB) integrity, but has no effect on inflammatory cells infiltration. In conclusion, butyrate improves outcomes in aged mice after stroke by promoting angiogenesis and BBB integrity and reducing leukocyte infiltration. To some extent, IL-22 may contribute to butyrate treatment induced vascular remodeling and increased BBB integrity responses in aged stroke mice.

The Dialogue Between Neuroinflammation and Adult Neurogenesis: Mechanisms Involved and Alterations in Neurological Diseases

Adult neurogenesis occurs mainly in the subgranular zone of the hippocampal dentate gyrus and the subventricular zone of the lateral ventricles. Evidence supports the critical role of adult neurogenesis in various conditions, including cognitive dysfunction, Alzheimer's disease (AD), and Parkinson's disease (PD). Several factors can alter adult neurogenesis, including genetic, epigenetic, age, physical activity, diet, sleep status, sex hormones, and central nervous system (CNS) disorders, exerting either pro-neurogenic or anti-neurogenic effects. Compelling evidence suggests that any insult or injury to the CNS, such as traumatic brain injury (TBI), infectious diseases, or neurodegenerative disorders, can provoke an inflammatory response in the CNS. This inflammation could either promote or inhibit neurogenesis, depending on various factors, such as chronicity and severity of the inflammation and underlying neurological disorders. Notably, neuroinflammation, driven by different immune components such as activated glia, cytokines, chemokines, and reactive oxygen species, can regulate every step of adult neurogenesis, including cell proliferation, differentiation, migration, survival of newborn neurons, maturation, synaptogenesis, and neuritogenesis. Therefore, this review aims to present recent findings regarding the effects of various components of the immune system on adult neurogenesis and to provide a better understanding of the role of neuroinflammation and neurogenesis in the context of neurological disorders, including AD, PD, ischemic stroke (IS), seizure/epilepsy, TBI, sleep deprivation, cognitive impairment, and anxiety- and depressive-like behaviors. For each disorder, some of the most recent therapeutic candidates, such as curcumin, ginseng, astragaloside, boswellic acids, andrographolide, caffeine, royal jelly, estrogen, metformin, and minocycline, have been discussed based on the available preclinical and clinical evidence.

Micro-RNAs Shuttled by Extracellular Vesicles Secreted from Mesenchymal Stem Cells Dampen Astrocyte Pathological Activation and Support Neuroprotection in In-Vitro Models of ALS

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with no effective cure. Astrocytes display a toxic phenotype in ALS and contribute to motoneuron (MN) degeneration. Modulating astrocytes' neurotoxicity can reduce MN death. Our previous studies showed the beneficial effect of mesenchymal stem cell (MSC) administration in SOD1^G93A ALS mice, but the mechanisms are still unclear. We postulated that the effects could be mediated by extracellular vesicles (EVs) secreted by MSCs. We investigated, by immunohistochemical, molecular, and in vitro functional analyses, the activity of MSC-derived EVs on the pathological phenotype and neurotoxicity of astrocytes isolated from the spinal cord of symptomatic SOD1^G93A mice and human astrocytes (iAstrocytes) differentiated from inducible neural progenitor cells (iNPCs) of ALS patients. In vitro EV exposure rescued mouse and human ALS astrocytes' neurotoxicity towards MNs. EVs significantly dampened the pathological phenotype and neuroinflammation in SOD1^G93A astrocytes. In iAstrocytes, exposure to EVs increased the antioxidant factor Nrf2 and reduced reactive oxygen species. We previously found nine miRNAs upregulated in MSC-derived EVs. Here, the transfection of SOD1^G93A astrocytes with single miRNA mimics reduced astrocytes' activation and the expression of neuroinflammatory factors. Moreover, miR-466q and miR-467f mimics downregulate Mapk11, while miR-466m-5p and miR-466i-3p mimics promote the nuclear translocation of Nrf2. In iAstrocytes, transfection with miR-29b-3p mimic upregulated NQO1 antioxidant activity and reduced neurotoxicity towards MNs. MSC-derived EVs modulate astrocytes' reactive phenotype and neurotoxicity through anti-inflammatory and antioxidant-shuttled miRNAs, thus representing a therapeutic strategy in ALS.

Influence of CYP3A5, IL-10 polymorphisms and metabolism rate on tacrolimus exposure in renal post-transplant recipients

Aim: To investigate the influence of CYP3A5 and IL-10 polymorphisms on tarcolimus metabolism and renal function for renal transplantation recipients at a stable period. Methods: CYP3A5 and IL-10 polymorphisms, together with other clinical factors, were collected for 149 renal transplantation patients at postoperative stable period. Statistics analysis was performed to explore key factors affecting tarcolimus metabolism. Results: CYP3A5 6986A >G and IL-10 -819C >T significantly impacted tacrolimus metabolism (p < 0.001). CYP3A5 6986A >G G allele and IL-10 -819C >T T allele were associated with poorer tacrolimus metabolic capability. Patients with various tacrolimus metabolism rates presented little difference in renal functions at stable period. Conclusion: Genotyping of CYP3A5 and IL-10 might benefit the precision dosage of tacrolimus for renal transplantation recipients.

Paradoxical roles for programmed cell death signaling during viral infection of the central nervous system

Programmed cell death (PCD) is an essential mechanism of antimicrobial defense. Recent work has revealed an unexpected diversity in the types of PCD elicited during infection, as well as defined unique roles for different PCD modalities in shaping the immune response. Here, we review recent work describing unique ways in which PCD signaling operates within the infected central nervous system (CNS). These studies reveal striking complexity in the regulation of PCD signaling by CNS cells, including both protective and pathological outcomes in the control of infection. Studies defining the specialized molecular mechanisms shaping PCD responses in the CNS promise to yield much needed new insights into the pathogenesis of neuroinvasive viral infection, informing future therapeutic development.

An integrated cytokine and kynurenine network as the basis of neuroimmune communication

Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.

Transcriptional Profiling of Phagocytic Leukocytes and Microglia Reveals a Critical Role for Reactive Oxygen Species in Biofilm Containment during Staphylococcus aureus Craniotomy Infection

Craniotomies are performed to treat a variety of intracranial pathology. Surgical site infection remains a complication of craniotomy despite the use of prophylactic antibiotics and universal sterile precautions. Infections occur in 1-3% of procedures, with approximately half caused by Staphylococcus aureus that forms a biofilm on the bone flap and is recalcitrant to systemic antibiotic therapy. We used an S. aureus-dsRed construct to compare the phagocytic capacity of leukocytes and microglia in vitro and in vivo using a mouse model of craniotomy infection. In addition, single-cell RNA sequencing (scRNA-seq) was applied to determine whether a transcriptional signature could be identified for phagocytic versus nonphagocytic cells in vivo. S. aureus was phagocytosed to equivalent extents in microglia, macrophages, neutrophils, and granulocytic myeloid-derived suppressor cells in vitro; however, microglial uptake of S. aureus was limited in vivo, whereas the other leukocyte populations exhibited phagocytic activity. scRNA-seq comparing the transcriptional signatures of phagocytic (S. aureus-dsRed+) versus nonphagocytic (S. aureus-dsRed-) leukocytes identified classical pathways enriched in phagocytic cells (i.e., reactive oxygen species [ROS]/reactive nitrogen species, lysosome, iron uptake, and transport), whereas nonphagocytic populations had increased ribosomal, IFN, and hypoxia signatures. scRNA-seq also revealed a robust ROS profile, which led to the exploration of craniotomy infection in NADPH oxidase 2 knockout mice. S. aureus burden, leukocyte recruitment, and intracellular bacterial load were significantly increased in NADPH oxidase 2 KO compared with wild-type animals. Collectively, these results highlight the importance of ROS generation in phagocytes for S. aureus biofilm containment, but not clearance, during craniotomy infection.

Troxerutin attenuates insulin resistance via pancreatic IL-22/JAK1/STAT3 signaling activation in dihydrotestosterone-induced polycystic ovary syndrome rats

Polycystic ovary syndrome (PCOS) is an extremely common endocrine-metabolic disorder and the main cause of infertility in premenopausal women, thus targeted treatments are sorely needed. Accumulative evidence showed that exogenous supplementation of IL-22 in PCOS mice may be of significant positive effect on insulin resistance (IR), a root causative factor for this condition, but much remained unknown about its mechanism. According to our previous study, troxerutin, a common anticoagulant and thrombolytic agent in clinic, alleviated various PCOS-like phenotypes in dihydrotestosterone (DHT)-treated rat model with unclear mechanism. Here, glucose tolerance tests (GTTs), insulin tolerance tests (ITTs), and homeostatic model assessment of insulin resistance (HOMA-IR) analyses revealed that troxerutin treatment in DHT-treated rats also significantly improved insulin resistance and enhanced serum IL-22 levels, which thereby activated IL-22R1/Janus kinase 1 (JAK1)/signal transducer and activator of transcription-3 (STAT3) signaling pathway in pancreatic islet. This protective effect of troxerutin on insulin resistance improvement was blocked by an inhibitor of p-STAT3, S3I-201. Troxerutin administration to DHT rats decreased the relative abundance of Bifidobacterium and enhanced secondary bile acid profiles, which were positively correlated with serum IL-22 concentration. Conclusively, the present study reported that troxerutin is an endogenous enhancer of IL-22 and the effect of troxerutin on insulin resistance improvement was via IL-22R1/JAK1/STAT3 signaling activation in a DHT-induced PCOS rat model. These insights may be translated into a primary therapeutic agent for PCOS with insulin resistance and hyperandrogenism.NEW & NOTEWORTHY Troxerutin decreased the relative abundance of Bifidobacterium, along with enhancement of secondary bile acids/IL-22 system, which thereby activated its downstream IL-22R1/JAK1/STAT3 signaling pathway in pancreatic β cells, subsequently attenuated insulin resistance (IR), hyperandrogenism and PCOS-like phenotypes in DHT-induced PCOS rat models. Troxerutin is an endogenous IL-22 enhancer and may be of therapeutic value for PCOS with insulin resistance.

Cognitive dysfunction associated with COVID-19: Prognostic role of circulating biomarkers and microRNAs

COVID-19 is renowned as a multi-organ disease having subacute and long-term effects with a broad spectrum of clinical manifestations. The evolving scientific and clinical evidence demonstrates that the frequency of cognitive impairment after COVID-19 is high and it is crucial to explore more clinical research and implement proper diagnostic and treatment strategies. Several central nervous system complications have been reported as comorbidities of COVID-19. The changes in cognitive function associated with neurodegenerative diseases develop slowly over time and are only diagnosed at an already advanced stage of molecular pathology. Hence, understanding the common links between COVID-19 and neurodegenerative diseases will broaden our knowledge and help in strategizing prognostic and therapeutic approaches. The present review focuses on the diverse neurodegenerative changes associated with COVID-19 and will highlight the importance of major circulating biomarkers and microRNAs (miRNAs) associated with the disease progression and severity. The literature analysis showed that major proteins associated with central nervous system function, such as Glial fibrillary acidic protein, neurofilament light chain, p-tau 181, Ubiquitin C-terminal hydrolase L1, S100 calcium-binding protein B, Neuron-specific enolase and various inflammatory cytokines, were significantly altered in COVID-19 patients. Furthermore, among various miRNAs that are having pivotal roles in various neurodegenerative diseases, miR-146a, miR-155, Let-7b, miR-31, miR-16 and miR-21 have shown significant dysregulation in COVID-19 patients. Thus the review consolidates the important findings from the numerous studies to unravel the underlying mechanism of neurological sequelae in COVID-19 and the possible association of circulatory biomarkers, which may serve as prognostic predictors and therapeutic targets in future research.

Exploring the role of interleukin-27 as a regulator of neuronal survival in central nervous system diseases

Interleukin-27 is a pleiotropic cytokine that is involved in tissue responses to infection, cell stress, neuronal disease, and tumors. Recent studies in various tissues indicate that interleukin-27 has complex activating and inhibitory properties in innate and acquired immunity. The availability of recombinant interleukin-27 protein and mice with genetic deletions of interleukin-27, its receptors and signaling mediators have helped define the role of interleukin-27 in neurodegenerative diseases. Interleukin-27 has been well-characterized as an important regulator of T cell activation and differentiation that enhances or suppresses T cell responses in autoimmune conditions in the central nervous system. Evidence is also accumulating that interleukin-27 has neuroprotective activities in the retina and brain. Interleukin-27 is secreted from and binds to infiltrating microglia, macrophage, astrocytes, and even neurons and it promotes neuronal survival by regulating pro- and anti-inflammatory cytokines, neuroinflammatory pathways, oxidative stress, apoptosis, autophagy, and epigenetic modifications. However, interleukin-27 can have the opposite effect and induce inflammation and cell death in certain situations. In this review, we describe the current understanding of regulatory activities of interleukin-27 on cell survival and inflammation and discuss its mechanisms of action in the brain, spinal cord, and retina. We also review evidence for and against the therapeutic potential of interleukin-27 for dampening harmful neuroinflammatory responses in central nervous system diseases.

The effect of hydro alcoholic extract of Nigella sativa seeds on inflammatory mediators in C6 glioma cell line

SUBJECT

Nigella sativa (N. sativa) is a highly valued nutritional plant, which has long been used in traditional medicine to treat a variety of human diseases. The multifaceted pharmacological impacts of N. sativa, such as attenuating oxidative stress and inflammation, make it a suitable therapeutic candidate against cardiovascular, hepatic, and neurological disorders as well as cancer. Therefore, the current study aimed to evaluate the effect of the hydroalcoholic extract of N. sativa seeds on several pro-inflammatory cytokines in the C6 glioma cell line and to compare it with the effect of the extract on the normal fibroblast cell line.

METHODS

C6 and fibroblast cell lines were treated with the extract of N. sativa seeds, and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was performed to determine the half-maximal inhibitory concentration (IC50) after 72h of treatment. Real-time polymerase chain reaction (RT-PCR) was carried out to assess the expression levels of interleukin (IL)-6, IL-10, tumor necrosis factor-alpha (TNF-α), and transforming growth factor- β1 (TGF-β1) at the mRNA level in both cell lines after 72h of treatment with non-toxic and IC50 concentrations obtained from C6 cell line.

RESULTS

The IC50 values for the hydroalcoholic extract of N. sativa seeds were 260±20μg/mL in the C6 cell line and 398±27μg/mL in fibroblast cells. The real-time PCR results indicated that the treatment of C6 and fibroblast cells with the extract at the IC50 value of N. sativa in C6 for 72h could increase the mRNA expression levels of IL-10 and reduce the mRNA expression levels of IL-6, TNF-α, and TGF-β1 in C6 and fibroblast cells. The N. sativa extract showed a higher anti-inflammatory effect on C6 cells in comparison with fibroblast cells.

CONCLUSIONS

Regarding the anti-inflammatory effect of Nigella sativa in C6 cell line, it may be considered a promising candidate to fortify antitumor actions in combination with other therapeutic options in the treatment of patients with GBM.

Single cell and spatial transcriptomic analyses reveal microglia-plasma cell crosstalk in the brain during Trypanosoma brucei infection

Human African trypanosomiasis, or sleeping sickness, is caused by the protozoan parasite Trypanosoma brucei and induces profound reactivity of glial cells and neuroinflammation when the parasites colonise the central nervous system. However, the transcriptional and functional responses of the brain to chronic T. brucei infection remain poorly understood. By integrating single cell and spatial transcriptomics of the mouse brain, we identify that glial responses triggered by infection are readily detected in the proximity to the circumventricular organs, including the lateral and 3rd ventricle. This coincides with the spatial localisation of both slender and stumpy forms of T. brucei. Furthermore, in silico predictions and functional validations led us to identify a previously unknown crosstalk between homeostatic microglia and Cd138+ plasma cells mediated by IL-10 and B cell activating factor (BAFF) signalling. This study provides important insights and resources to improve understanding of the molecular and cellular responses in the brain during infection with African trypanosomes.

Combination therapy with interferon-gamma as a potential therapeutic medicine in rat's glioblastoma: A multi-mechanism evaluation

BACKGROUND

This study assessed the effects of single or combined administration of temozolomide (TMZ) and interferon-gamma (IFN-ᵞ) on anxiety-like behaviors, balance disorders, learning and memory, TNF-α, IL-10, some oxidant and antioxidants factors with investigating the toll-like receptor-4 (TLR4) and p-CREB signaling pathway in C6-induced glioblastoma of rats.

METHODS

40 male Sprague-Dawley rats bearing intra-caudate nucleus (CN) culture medium or C6 inoculation were randomly divided into five groups as follows: Sham, Tumor, TMZ, IFN-ᵞ and a TMZ + IFN-ᵞ combination. The open-field test (OFT), elevated plus maze (EPM), rotarod, and passive avoidance test (PAT) were done on days 14-17. On day 17 after tumor implantation, brain tissues were extracted for histopathological evaluation. TNF-α, IL-10, SOD, GPX, TAC, MDA, the protein level of TLR4 and p-CREB was measured.

RESULTS

Combination therapy inhibited the growth of the tumor. Treatment groups alleviated tumor-induced anxiety-like behaviors and improved imbalance and memory impairment. SOD, GPX, and TAC decreased in the tumor group. The combination group augmented GPX and TAC. MDA decreased in treatment groups. TMZ, IFN-ᵞ reduced tumor-increased TNF-α and IL-10 level. The combination group declined TNF-α level in serum and IL-10 level in serum and brain. Glioblastoma induced significant upregulation of TLR4 and p-CREB in the brain which inhibited by IFN-ᵞ and TMZ+ IFN-ᵞ.

CONCLUSION

The beneficial effects of TMZ, IFN-ᵞ, and TMZ+ IFN-ᵞ on neurocognitive functioning of rats with C6-induced glioblastoma may be mediated via modulating oxidative stress, reduced cytokines, and the downregulation of expression of TLR4 and p-CREB. Combination treatment appears to be more effective than single treatment.

Electroacupuncture Stimulation Suppresses Postoperative Inflammatory Response and Hippocampal Neuronal Injury

Postoperative cognitive dysfunction (POCD) is consequence of anesthesia and surgery that primarily affects older people. The prevention and treatment of POCD has drawn an increasing attention in recent decades. Here, we established the animal model mimicked POCD after femoral fracture surgery, and analyze the effect of acupuncture stimulation on postoperative cognitive function after femoral fracture surgery. Compared with the mock group, the cognitive function performance was significantly decreased both in the anaesthesia group and the surgery group, between which the symptoms were more severe in the surgery group. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus were observed in the surgery group, but only peripheral inflammation response was detected in the anaesthesia group. These findings indicated the POCD was the synergistic outcome of anaesthesia and surgical stimulation but with different pathogenic mechanism. The surgery with mental tri-needles (surgery+MTN) group outperformed the surgery group in terms of cognitive function performance. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus was significantly reduced by the electroacupuncture stimulation. Our findings indicated the protection of electroacupuncture form POCD after femoral fracture surgery is related to the inhibition of inflammation response and neuron impairment.

The cytokine IL-27 reduces inflammation and protects photoreceptors in a mouse model of retinal degeneration

BACKGROUND

Retinal degenerative diseases are a group of conditions characterized by photoreceptor death and vision loss. Excessive inflammation and microglial activation contribute to the pathology of retinal degenerations and a major focus in the field is identifying more effective anti-inflammatory therapeutic strategies that promote photoreceptor survival. A major challenge to developing anti-inflammatory treatments is to selectively suppress detrimental inflammation while maintaining beneficial inflammatory responses. We recently demonstrated that endogenous levels of the IL-27 cytokine were upregulated in association with an experimental treatment that increased photoreceptor survival. IL-27 is a pleiotropic cytokine that regulates tissue reactions to infection, neuronal disease and tumors by inducing anti-apoptotic and anti-inflammatory genes and suppressing pro-inflammatory genes. IL-27 is neuroprotective in the brain, but its function during retinal degeneration has not been investigated. In this study, we investigated the effect of IL-27 in the rd10 mouse model of inherited photoreceptor degeneration.

METHODS

Male and female rd10 mice were randomly divided into experimental (IL-27) and control (saline) groups and intravitreally injected at age post-natal day (P) 18. Retina function was analyzed by electroretinograms (ERGs), visual acuity by optomotor assay, photoreceptor death by TdT-mediated dUTP nick-end labeling (TUNEL) assay, microglia/macrophage were detected by immunodetection of IBA1 and inflammatory mediators by cytoplex and QPCR analysis. The distribution of IL-27 in the retina was determined by immunohistochemistry on retina cross-sections and primary Muller glia cultures.

RESULTS

We demonstrate that recombinant IL-27 decreased photoreceptor death, increased retinal function and reduced inflammation in the rd10 mouse model of retinal degeneration. Furthermore, IL-27 injections led to lower levels of the pro-inflammatory proteins Ccl22, IL-18 and IL-12. IL-27 expression was localized to Muller glia and IL-27 receptors to microglia, which are key cell types that regulate photoreceptor survival.

CONCLUSION

Our results identify for the first time anti-inflammatory and neuroprotective activities of IL-27 in a genetic model of retinal degeneration. These findings provide new insight into the therapeutic potential of anti-inflammatory cytokines as a treatment for degenerative diseases of the retina.

Further Evidence of Neuroprotective Effects of Recombinant Human Erythropoietin and Growth Hormone in Hypoxic Brain Injury in Neonatal Mice

Experimental in vivo data have recently shown complementary neuroprotective actions of rhEPO and growth hormone (rhGH) in a neonatal murine model of hypoxic brain injury. Here, we hypothesized that rhGH and rhEPO mediate stabilization of the blood−brain barrier (BBB) and regenerative vascular effects in hypoxic injury to the developing brain. Using an established model of neonatal hypoxia, neonatal mice (P7) were treated i.p. with rhGH (4000 µg/kg) or rhEPO (5000 IU/kg) 0/12/24 h after hypoxic exposure. After a regeneration period of 48 h or 7 d, cerebral mRNA expression of Vegf-A, its receptors and co-receptors, and selected tight junction proteins were determined using qRT-PCR and ELISA. Vessel structures were assessed by Pecam-1 and occludin (Ocln) IHC. While Vegf-A expression increased significantly with rhGH treatment (p < 0.01), expression of the Vegfr and TEK receptor tyrosine kinase (Tie-2) system remained unchanged. RhEPO increased Vegf-A (p < 0.05) and Angpt-2 (p < 0.05) expression. While hypoxia reduced the mean vessel area in the parietal cortex compared to controls (p < 0.05), rhGH and rhEPO prevented this reduction after 48 h of regeneration. Hypoxia significantly reduced the Ocln+ fraction of cortical vascular endothelial cells. Ocln signal intensity increased in the cortex in response to rhGH (p < 0.05) and in the cortex and hippocampus in response to rhEPO (p < 0.05). Our data indicate that rhGH and rhEPO have protective effects on hypoxia-induced BBB disruption and regenerative vascular effects during the post-hypoxic period in the developing brain.

Helminthic dehydrogenase drives PGE2 and IL-10 production in monocytes to potentiate Treg induction

Immunoregulation of inflammatory, infection‐triggered processes in the brain constitutes a central mechanism to control devastating disease manifestations such as epilepsy. Observational studies implicate the viability of Taenia solium cysts as key factor determining severity of neurocysticercosis (NCC), the most common cause of epilepsy, especially in children, in Sub‐Saharan Africa. Viable, in contrast to decaying, cysts mostly remain clinically silent by yet unknown mechanisms, potentially involving Tregs in controlling inflammation. Here, we show that glutamate dehydrogenase from viable cysts instructs tolerogenic monocytes to release IL‐10 and the lipid mediator PGE₂. These act in concert, converting naive CD4⁺ T cells into CD127⁻CD25^hiFoxP3⁺CTLA‐4⁺ Tregs, through the G protein‐coupled receptors EP2 and EP4 and the IL‐10 receptor. Moreover, while viable cyst products strongly upregulate IL‐10 and PGE₂ transcription in microglia, intravesicular fluid, released during cyst decay, induces pro‐inflammatory microglia and TGF‐β as potential drivers of epilepsy. Inhibition of PGE₂ synthesis and IL‐10 signaling prevents Treg induction by viable cyst products. Harnessing the PGE₂‐IL‐10 axis and targeting TGF‐ß signaling may offer an important therapeutic strategy in inflammatory epilepsy and NCC.

Indoor green wall affects health-associated commensal skin microbiota and enhances immune regulation: a randomized trial among urban office workers

Urbanization reduces microbiological abundance and diversity, which has been associated with immune mediated diseases. Urban greening may be used as a prophylactic method to restore microbiological diversity in cities and among urbanites. This study evaluated the impact of air-circulating green walls on bacterial abundance and diversity on human skin, and on immune responses determined by blood cytokine measurements. Human subjects working in offices in two Finnish cities (Lahti and Tampere) participated in a two-week intervention, where green walls were installed in the rooms of the experimental group. Control group worked without green walls. Skin and blood samples were collected before (Day0), during (Day14) and two weeks after (Day28) the intervention. The relative abundance of genus Lactobacillus and the Shannon diversity of phylum Proteobacteria and class Gammaproteobacteria increased in the experimental group. Proteobacterial diversity was connected to the lower proinflammatory cytokine IL-17A level among participants in Lahti. In addition, the change in TGF-β1 levels was opposite between the experimental and control group. As skin Lactobacillus and the diversity of Proteobacteria and Gammaproteobacteria are considered advantageous for skin health, air-circulating green walls may induce beneficial changes in a human microbiome. The immunomodulatory potential of air-circulating green walls deserves further research attention.

Inhibition of Carrageenan-Induced Acute Inflammation in Mice by the Microgramma vacciniifolia Frond Lectin (MvFL)

Most anti-inflammatory drugs used nowadays have an excessive cost and their prolonged use has been connected with several injurious effects. Thus, the search for new anti-inflammatory agents is increasing. Lectins are carbohydrate-interacting proteins that can modulate immune response and the release of inflammation mediators. The Microgramma vacciniifolia frond lectin (MvFL) was previously reported to be an immunomodulatory agent in vitro. This work aimed to evaluate the effects of MvFL on the in vivo inflammatory status in the carrageenan-induced peritonitis and paw edema, using female Swiss mice. The animals were pretreated intraperitoneally with MvFL (5 and 10 mg/kg). In the peritonitis assay, the total and differential migration of white blood cells was evaluated, as well as the levels of cytokines, nitric oxide (NO), and total proteins in the peritoneal fluid. In the paw edema evaluation, the paw volume was measured in the early (from 30 min–2 h) and late (3–4 h) phases of edema formation. MvFL (5 and 10 mg/kg) was efficient in reducing neutrophil infiltration, pro-inflammatory cytokines (IL-6, IL-17, and TNF-α), NO, and protein content in the peritoneal fluid. It also repressed the edema formation in the late phase of the assay. In conclusion, MvFL showed inhibitory effects in in vivo acute inflammation, which encouraged future studies exploiting its immunomodulatory ability.

Chronic IL-10 overproduction disrupts microglia-neuron dialogue similar to aging, resulting in impaired hippocampal neurogenesis and spatial memory

The subgranular zone of the dentate gyrus is an adult neurogenic niche where new neurons are continuously generated. A dramatic hippocampal neurogenesis decline occurs with increasing age, contributing to cognitive deficits. The process of neurogenesis is intimately regulated by the microenvironment, with inflammation being considered a strong negative factor for this process. Thus, we hypothesize that the reduction of new neurons in the aged brain could be attributed to the age-related microenvironmental changes towards a pro-inflammatory status. In this work, we evaluated whether an anti-inflammatory microenvironment could counteract the negative effect of age on promoting new hippocampal neurons. Surprisingly, our results show that transgenic animals chronically overexpressing IL-10 by astrocytes present a decreased hippocampal neurogenesis in adulthood. This results from an impairment in the survival of neural newborn cells without differences in cell proliferation. In parallel, hippocampal-dependent spatial learning and memory processes were affected by IL-10 overproduction as assessed by the Morris water maze test. Microglial cells, which are key players in the neurogenesis process, presented a different phenotype in transgenic animals characterized by high activation together with alterations in receptors involved in neuronal communication, such as CD200R and CX3CR1. Interestingly, the changes described in adult transgenic animals were similar to those observed by the effect of normal aging. Thus, our data suggest that chronic IL-10 overproduction mimics the physiological age-related disruption of the microglia-neuron dialogue, resulting in hippocampal neurogenesis decrease and spatial memory impairment.

Biological Role, Mechanism of Action and the Importance of Interleukins in Kidney Diseases

Each year, the number of patients who are diagnosed with kidney disease too late is increasing, which leads to permanent renal failure. This growing problem affects people of every age, sex and origin, and its full etiopathogenesis is not fully understood, although the involvement of genetic susceptibility, infections, immune disorders or high blood pressure is suggested. Difficulties in making a correct and quick diagnosis are caused by the lack of research on early molecular markers, as well as educational and preventive activities among the public, which leads to the late detection of kidney diseases. An important role in the homeostasis and disease progression, including kidney diseases, is attributed to interleukins, which perform several biological functions and interact with other cells and tissues of the body. The aim of this article was to systematize the knowledge about the biological functions performed by interleukins in humans and their involvement in kidney diseases development. In our work, we took into account the role of interleukins in acute and chronic kidney disease and kidney transplantation.

Prolactin and Its Altered Action in Alzheimer's Disease and Parkinson's Disease

BACKGROUND

Prolactin (PRL) is one of the most diverse pituitary hormones and is known to modulate normal neuronal function and neurodegenerative conditions. Many studies have described the influence that PRL has on the central nervous system and addressed its contribution to neurodegeneration, but little is known about the mechanisms responsible for the effects of PRL on neurodegenerative disorders, especially on Alzheimer's disease (AD) and Parkinson's disease (PD).

SUMMARY

We review and summarize the existing literature and current understanding of the roles of PRL on various PRL aspects of AD and PD.

KEY MESSAGES

In general, PRL is viewed as a promising molecule for the treatment of AD and PD. Modulation of PRL functions and targeting of immune mechanisms are needed to devise preventive or therapeutic strategies.