Search

Progranulin is an evolutionarily conserved protein that has been implicated in human neurodevelopmental and neurodegenerative diseases. Human progranulin is comprised of multiple cysteine-rich, biologically active granulin peptides. Granulin peptides accumulate with age and stress, however their functional contributions relative to full-length progranulin remain unclear. To address this, we generated C. elegans strains that produced quantifiable levels of both full-length progranulin/PGRN-1 protein and cleaved granulin peptide. Using these strains, we demonstrated that even in the presence of intact PGRN-1, granulin peptides suppressed the activity of the lysosomal aspartyl protease activity, ASP-3/CTSD. Granulin peptides were also dominant over PGRN-1 in compromising animal fitness as measured by progress through development and stress response. Finally, the degradation of human TDP-43 was impaired when the granulin to PGRN-1 ratio was increased, representing a disease-relevant downstream impact of impaired lysosomal function. In summary, these studies suggest that not only absolute progranulin levels, but also the balance between full-length progranulin and its cleavage products, is important in regulating lysosomal biology. Given its relevance in human disease, this suggests that the processing of progranulin into granulins should be considered as part of disease pathobiology and may represent a site of therapeutic intervention.

Background: Apraxia has been identified in all clinical forms of frontotemporal lobar degeneration (FTLD). The characteristics of apraxia symptoms and their underlying cognitive/motor basis are not fully understood. This study investigated apraxia in pathological subtypes of FTLD. Methods: The study constituted a retrospective review of 115 pathologically confirmed cases of FTLD from a single cognitive neurology centre. Patients in whom apraxia had been documented as a notable clinical characteristic were identified. Apraxia features, demographic, cognitive, neurological, and imaging findings were recorded. Results: Eighteen patients were identified: 12 with FTLD-tau pathology (7 corticobasal degeneration (CBD), four Pick type and one progressive supranuclear palsy (PSP)) and six with FTLD-TDP pathology, all type A and four linked to progranulin gene mutations. Apraxia as a dominant presenting feature was typically associated with tau pathologies, whereas it emerged in the context of aphasia in TDP pathology. Apraxia typically predominated in one body part (face or limb) in tau but not TDP pathology. Relatively preserved activities in daily life were associated with TDP. Apraxia of speech was associated with tau pathology. Pick-type pathology was linked to symmetrical atrophy and late development of limb rigidity. Conclusion: Apraxia in FTLD subtypes has variable characteristics. Apraxia associated with CBD pathology conformed to criteria for probable corticobasal syndrome (CBS), whereas apraxia with Pick-type pathology did not. Apraxia in patients with TDP-A pathology was interpreted as one manifestation of their generalised communication disorder. Apraxia in FTLD may have distinct cognitive and motor substrates that require prospective investigation. [ABSTRACT FROM AUTHOR]

Background: Progranulin is a secreted glycoprotein that regulates inflammation and wound healing. However, plasma progranulin levels in the acute phase and their clinical significance in patients with acute myocardial infarction (AMI) remain to be elucidated. Objective: We aimed to investigate the relationship between the increase in plasma progranulin levels in the acute phase and the recovery of left ventricular function in the chronic phase in AMI patients. Method and result: Eighteen AMI patients were followed up for 6 months. Blood samples were collected from the antecubital vein on day 0 (on admission) and day 7 in the acute phase. The control group consisted of patients without significant coronary artery stenosis, as assessed by cardiac catheterization (n = 16). Plasma progranulin levels were measured by enzyme-linked immunosorbent assay. Echocardiography was performed in the acute (within 7 days) and chronic (6 months) phases of AMI to evaluate left ventricular ejection fraction using the modified Simpson's method. Plasma progranulin levels in the AMI group on day 0 (69.5 ± 24.6 ng/mL) were similar to those in the control group (84.2 ± 47.1 ng/mL). There was a significant increase in progranulin levels in the AMI group on day 7 (104.2 ± 52.0 ng/mL) compared with day 0. The increase in plasma progranulin levels in the acute phase was positively correlated with the increase in left ventricular ejection fraction between the acute and chronic phases. Among various factors, only plasma progranulin levels were favorably correlated with left ventricular functional recovery in the chronic phase. Conclusion: The increase in plasma progranulin levels in the acute phase may serve as a predictive biomarker and a contributer for the recovery of left ventricular function in the chronic phase in patients with AMI. [ABSTRACT FROM AUTHOR]

This narrative review explores the current landscape of blood biomarkers in Frontotemporal dementia (FTD). Neurofilament light chain (NfL) may be useful in the differentiation of behavioral variant FTD from primary psychiatric disorders (PPDs) or dementia with Lewy bodies (DLB). In prodromal FTD and presymptomatic mutation carriers (GRN, MAPT, C9orf72), elevated NfL may herald pheno-conversion to full-blown dementia. Baseline NfL correlates with steeper neuroanatomical changes and cognitive, behavioral and functional decline, making NfL promising in monitoring disease progression. Phosphorylated neurofilament heavy chain (pNfH) levels have a potential limited role in the demarcation of the conversion stage to full-blown FTD. Combined NfL and pNfH measurements may allow a wider stage stratification. Total tau levels lack applicability in the framework of FTD. p-tau, on the other hand, is of potential value in the discrimination of FTD from Alzheimer's dementia. Progranulin concentrations could serve the identification of GRN mutation carriers. Glial fibrillary acidic protein (GFAP) may assist in the differentiation of PPDs from behavioral variant FTD and the detection of GRN mutation carriers (additional research is warranted). Finally, TAR DNA-binding protein-43 (TDP-43) appears to be a promising diagnostic biomarker for FTD. Its potential in distinguishing TDP-43 pathology from other FTD-related pathologies requires further research. [ABSTRACT FROM AUTHOR]

• Inflammation plays a crucial role in neurodegeneration, including Frontotemporal Dementia (FTD). • Several cytokines are upregulated in plasma from genetic FTD. • On the contrary, IL-1α levels are decreased, even in presymptomatic stages. Inflammation has been proposed as a crucial player in neurodegeneration, including Frontotemporal Dementia (FTD). A few studies on sporadic FTD lead to inconclusive results, whereas large studies on genetic FTD are lacking. The aim of this study is to determine cytokine and chemokine plasma circulating levels in a large cohort of genetic FTD, collected within the GENetic Frontotemporal dementia Initiative (GENFI). Mesoscale technology was used to analyse levels of 30 inflammatory factors in 434 plasma samples, including 94 Symptomatic Mutation carriers [(SMC); 15 with mutations in Microtubule Associated Protein Tau (MAPT) 34 in Progranulin (GRN) and 45 in Chromosome 9 Open Reading Frame (C9ORF) 72 ], 168 Presymptomatic Mutation Carriers (PMC; 34 MAPT , 70 GRN and 64 C9ORF72) and 173 Non-carrier Controls (NC)]. The following cytokines were significantly upregulated (P <0.05) in MAPT and GRN SMC versus NC: Tumor Necrosis Factor (TNF)α, Interleukin (IL)-7, IL-15, IL-16, IL-17A. Moreover, only in GRN SMC, additional factors were upregulated, including: IL-1β, IL-6, IL-10, IL-12/IL-23p40, eotaxin, eotaxin-3, Interferon γ-induced Protein (IP-10), Monocyte Chemotactic Protein (MCP)4. On the contrary, IL-1α levels were decreased in SMC compared with NC. Significantly decreased levels of this cytokine were also found in PMC, independent of the type of mutation. In SMC, no correlations between disease duration and cytokine and chemokine levels were found. Considering NfL and GFAP levels, as expected, significant increases were observed in SMC as compared to NC. These differences in mean values remain significant even when stratifying symptomatic patients by the mutated gene (P <0.0001). Considering instead the levels of NfL, GFAP, and the altered inflammatory molecules, no significant correlations emerged. We showed that inflammatory proteins are upregulated in MAPT and GRN SMC, with some specific factors altered in GRN only, whereas no changes were seen in C9ORF72 carriers. Notably, only IL-1α levels were decreased in both SMC and PMC, independent of the type of causal mutation, suggesting common modifications occurring in the preclinical phase of the disease. [ABSTRACT FROM AUTHOR]

Heterozygous loss-of-function mutations in the progranulin gene (GRN) are a major cause of frontotemporal dementia due to progranulin haploinsufficiency; complete deficiency of progranulin causes neuronal ceroid lipofuscinosis. Several progranulin-deficient mouse models have been generated, including both knockout mice and knockin mice harboring a common patient mutation (R493X). However, the GrnR493X mouse model has not been characterized completely. Additionally, while homozygous GrnR493X and Grn knockout mice have been extensively studied, data from heterozygous mice is still limited. Here, we performed more in-depth characterization of heterozygous and homozygous GrnR493X knockin mice, which includes biochemical assessments, behavioral studies, and analysis of fluid biomarkers. In the brains of homozygous GrnR493X mice, we found increased phosphorylated TDP-43 along with increased expression of lysosomal genes, markers of microgliosis and astrogliosis, pro-inflammatory cytokines, and complement factors. Heterozygous GrnR493X mice did not have increased TDP-43 phosphorylation but did exhibit limited increases in lysosomal and inflammatory gene expression. Behavioral studies found social and emotional deficits in GrnR493X mice that mirror those observed in Grn knockout mouse models, as well as impairment in memory and executive function. Overall, the GrnR493X knockin mouse model closely phenocopies Grn knockout models. Lastly, in contrast to homozygous knockin mice, heterozygous GrnR493X mice do not have elevated levels of fluid biomarkers previously identified in humans, including neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) in both plasma and CSF. These results may help to inform pre-clinical studies that use this Grn knockin mouse model and other Grn knockout models. [ABSTRACT FROM AUTHOR]

Parkinson's disease is one of the most common neurodegenerative disorders characterized by a multitude of motor and non-motor clinical symptoms resulting from the progressive and long-lasting abnormal loss of nigrostriatal dopaminergic neurons. Currently, the available treatments for patients with Parkinson's disease are limited and exert only symptomatic effects, without adequate signs of delaying or stopping the progression of the disease. Atsttrin constitutes the bioengineered protein which ultrastructure is based on the polypeptide chain frame of the progranulin (PGRN), which exerts anti-inflammatory effects through the inhibition of TNFα. The conducted preclinical studies suggest that the therapeutic implementation of Atsttrin may be potentially effective in the treatment of neurodegenerative diseases that are associated with the occurrence of neuroinflammatory processes. The aim of the proposed study was to investigate the effect of direct bilateral intracerebral administration of Atsttrin using stereotactic methods in the preclinical C57BL/6 mouse model of Parkinson's disease inducted by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. The analysis of the dose dependency effects of the increasing doses of Atsttrin has covered a number of parameters and markers regarding neurodegenerative processes and inflammatory responses including IL-1α, TNFα, IL-6, TH, and TG2 mRNA expressions. Accordingly, the evaluation of the changes in the neurochemical profile included DA, DOPAC, 3-MT, HVA, NA, MHPG, 5-HT, and 5-HIAA concentration levels. The intracerebral administration of Atsttrin into the striatum effectively attenuated the neuroinflammatory reaction in evaluated neuroanatomical structures. Furthermore, the partial restoration of monoamine content and its metabolic turnover were observed. In this case, taking into account the previously described pharmacokinetic profile and extrapolated bioavailability as well as the stability characteristics of Atsttrin, an attempt was made to describe as precisely as possible the quantitative and qualitative effects of increasing doses of the compound within the brain tissue microenvironment in the presented preclinical model of the disease. Collectively, this findings demonstrated that the intracerebral administration of Atsttrin may represent a potential novel therapeutic method for the treatment of Parkinson's disease. [ABSTRACT FROM AUTHOR]

Purpose: Glioblastoma (GBM), characterized by astrocytic tumorigenesis, remains one of the most prognostically challenging tumor types. Targeting entire GBM microenvironment using novel therapeutic factors is currently desired investigation approach. In this study, we focused on progranulin (PGRN), a regulator of diverse cellular functions. Recent studies implicated PGRN in the poor prognostics of GBM patients. However, the specific role of PGRN in the GBM microenvironment remains elusive. Methods: We utilized public databases of GBM patient and previous single-cell RNA sequence to examine association between PGRN expression and patient survival/grade, and expression levels of PGRN in each cell constituting the tumor microenvironment. To clarify the role of PGRN in Tumor-associated macrophage (TAM), we examined cell proliferation and expression of some proteins in murine GBM cells when cell supernatants derived from TAM of PGRN knockout (Grn−/−) or wild type mice were treated with murine GBM cells. Results: Our results reveal significant PGRN expression in macrophages within the GBM environment, suggesting an association between increased PGRN expression in macrophages and tumor malignancy. TAM induction led to PGRN expression enhancement. Treatment with Grn−/− mouse -derived bone marrow-derived macrophage (BMDM) supernatant resulted in diminished GBM cell proliferation and cell cycle- and mesenchymal GBM subtype-associated reduced protein expression. Furthermore, the Grn−/− mouse-derived BMDM supernatant treatment reduced the phosphorylated STAT3 expression in GBM cells, while the expression of IL-6 and IL-10, known STAT3 pathway activators, diminished in Grn−/− mouse-derived BMDMs. Conclusion: Our results suggest that macrophage-derived PGRN is pivotal for fostering malignant transformations within the tumor microenvironment. [ABSTRACT FROM AUTHOR]

Introduction: Progranulin (PGRN) is a holoprotein that is internalized and taken to the lysosome where it is processed to individual granulins (GRNs). PGRN is critical for successful aging, and insufficient levels of PGRN are associated with increased risk for developing neurodegenerative diseases like AD, PD, and FTD. A unifying feature among these diseases is dysregulation of peripheral immune cell populations. However, considerable gaps exist in our understanding of the function(s) of PGRN/GRNs in immune cells and their role in regulating centralperipheral neuroimmune crosstalk. One of the most upregulated genes and proteins in humans with GRN haploinsufficiency and in aged Grn knock-out (KO) mice is glycoprotein non-metastatic B (GPNMB) but its normal role within the context of immune crosstalk has not been elucidated. Methods: To address this gap, peritoneal macrophages (pMacs) from 5-to-6-month old WT and Grn KO mice were assessed for Gpnmb expression and stimulation-dependent cytokine release in the presence or absence of the Gpnmb extracellular domain (ECD). Cellular localization, as well as inhibition of, the microphthalmia-associated transcription factor (MITF) was assessed to determine its mechanistic role in Gpnmb overexpression in Grn KO pMacs. Results: We observed an increase in GPNMB protein and mRNA as a result of insufficient progranulin in peripheral immune cells at a very early age relative to previous reports on the brain. Stimulation-dependent cytokine release was decreased in the media of Grn KO pMacs relative to WT controls; a phenotype that could be mimicked in WT pMacs with the addition og GPNMB ECD. We also found that MITF is dysregulated in Grn KO pMacs; however, its nuclear translocation and activity are not required to rescue the immune dysregulation of Grn KO macrophages, suggesting redundancy in the system. Discussion: These findings highlight the fact that knowledge of early-stage disease mechanism(s) in peripheral populations may inform treatment strategies to delay disease progression at an early, prodromal timepoint prior to development of neuroinflammation and CNS pathology. [ABSTRACT FROM AUTHOR]

Background Aim Methods Results Conclusions Air pollutants, such as diesel exhaust particles (DEPs), induce respiratory disease exacerbation with neutrophilic infiltration. Progranulin (PGRN), an epithelial cell and macrophage‐derived secretory protein, is associated with neutrophilic inflammation. PGRN is digested into various derivatives at inflammatory sites and is involved in several inflammatory processes. PGRN and its derivatives likely regulate responses to DEP exposure in allergic airway inflammation.To investigate the role of PGRN and its derivatives in the regulation of responses to DEP exposure in allergic airway inflammation.A murine model of allergic airway inflammation was generated in PGRN‐deficient mice, and they were simultaneously exposed to DEP followed by intranasal administration of full‐length recombinant PGRN (PGRN‐FL) and a PGRN‐derived fragment (FBAC). Inflammatory status was evaluated by bronchoalveolar lavage fluid and histopathologic analyses. Human bronchial epithelial cells were stimulated with DEPs and house dust mites (HDMs), and the effect of FBAC treatment was evaluated by assessing various intracellular signaling molecules, autophagy markers, inflammatory cytokines, and intracellular oxidative stress.DEP exposure exaggerated neutrophilic inflammation, enhanced IL‐6 and CXCL15 secretions, and increased oxidative stress in the murine model; this effect was greater in PGRN‐deficient mice than in wild‐type mice. The DEP‐exposed mice with PGRN‐FL treatment revealed no change in neutrophil infiltration and higher oxidative stress status in the lungs. On the contrary, FBAC administration inhibited neutrophilic infiltration and reduced oxidative stress. In human bronchial epithelial cells, DEP and HDM exposure increased intracellular oxidative stress and IL‐6 and IL‐8 secretion. Decreased nuclear factor erythroid 2‐related factor 2 (Nrf2) expression and increased phosphor‐p62 and LC3B expression were also observed. FBAC treatment attenuated oxidative stress from DEP and HDM exposure.FBAC reduced neutrophilic inflammation exaggerated by DEP exposure in a mouse model of allergic airway inflammation by reducing oxidative stress. PGRN and PGRN‐derived proteins may be novel therapeutic agents in attenuating asthma exacerbation induced by air pollutant exposure. [ABSTRACT FROM AUTHOR]

Mutations in the human granulin (GRN) gene are associated with multiple diseases, including dementia disorders such as frontotemporal dementia (FTD) and limbic‐predominant age‐related TDP‐43 encephalopathy (LATE). We studied a Grn knockout (Grn‐KO) mouse model in order to evaluate a potential therapeutic strategy for these diseases using nicorandil, a commercially available agonist for the ABCC9/Abcc9‐encoded regulatory subunit of the “K+ATP” channel that is well‐tolerated in humans. Aged (13 months) Grn‐KO and wild‐type (WT) mice were treated as controls or with nicorandil (15 mg/kg/day) in drinking water for 7 months, then tested for neurobehavioral performance, neuropathology, and gene expression. Mortality was significantly higher for aged Grn‐KO mice (particularly females), but there was a conspicuous improvement in survival for both sexes treated with nicorandil. Grn‐KO mice performed worse on some cognitive tests than WT mice, but Morris Water Maze performance was improved with nicorandil treatment. Neuropathologically, Grn‐KO mice had significantly increased levels of glial fibrillary acidic protein (GFAP)‐immunoreactive astrocytosis but not ionized calcium binding adaptor molecule 1 (IBA‐1)‐immunoreactive microgliosis, indicating cell‐specific inflammation in the brain. Expression of several astrocyte‐enriched genes, including Gfap, were also elevated in the Grn‐KO brain. Nicorandil treatment was associated with a subtle shift in a subset of detected brain transcript levels, mostly related to attenuated inflammatory markers. Nicorandil treatment improved survival outcomes, cognition, and inflammation in aged Grn‐KO mice. [ABSTRACT FROM AUTHOR]

Introduction: Progranulin (PGRN) is a holoprotein that is internalized and taken to the lysosome where it is processed to individual granulins (GRNs). PGRN is critical for successful aging, and insufficient levels of PGRN are associated with increased risk for developing neurodegenerative diseases like AD, PD, and FTD. A unifying feature among these diseases is dysregulation of peripheral immune cell populations. However, considerable gaps exist in our understanding of the function(s) of PGRN/GRNs in immune cells and their role in regulating centralperipheral neuroimmune crosstalk. One of the most upregulated genes and proteins in humans with GRN haploinsufficiency and in aged Grn knock-out (KO) mice is glycoprotein non-metastatic B (GPNMB) but its normal role within the context of immune crosstalk has not been elucidated. Methods: To address this gap, peritoneal macrophages (pMacs) from 5-to-6-month old WT and Grn KO mice were assessed for Gpnmb expression and stimulation-dependent cytokine release in the presence or absence of the Gpnmb extracellular domain (ECD). Cellular localization, as well as inhibition of, the microphthalmia-associated transcription factor (MITF) was assessed to determine its mechanistic role in Gpnmb overexpression in Grn KO pMacs. Results: We observed an increase in GPNMB protein and mRNA as a result of insufficient progranulin in peripheral immune cells at a very early age relative to previous reports on the brain. Stimulation-dependent cytokine release was decreased in the media of Grn KO pMacs relative to WT controls; a phenotype that could be mimicked in WT pMacs with the addition og GPNMB ECD. We also found that MITF is dysregulated in Grn KO pMacs; however, its nuclear translocation and activity are not required to rescue the immune dysregulation of Grn KO macrophages, suggesting redundancy in the system. Discussion: These findings highlight the fact that knowledge of early-stage disease mechanism(s) in peripheral populations may inform treatment strategies to delay disease progression at an early, prodromal timepoint prior to development of neuroinflammation and CNS pathology. [ABSTRACT FROM AUTHOR]

Neonatal necrotizing enterocolitis (NEC) is a critical digestive disorder frequently affecting premature infants. Characterized by intestinal inflammation caused by activated M1 macrophages, modulation of macrophage polarization is considered a promising therapeutic strategy for NEC. It has been demonstrated that the growth factor‐like protein progranulin (PGRN), which plays roles in a number of physiological and pathological processes, can influence macrophage polarization and exhibit anti‐inflammatory characteristics in a number of illnesses. However, its role in NEC is yet to be investigated. Our research showed that the levels of PGRN were markedly elevated in both human and animal models of NEC. PGRN deletion in mice worsens NEC by encouraging M1 polarization of macrophages and escalating intestinal damage and inflammation. Intravenous administration of recombinant PGRN to NEC mice showed significant survival benefits and protective effects, likely due to PGRN's ability to inhibit M1 polarization and reduce the release of pro‐inflammatory factors. Our findings shed new light on PGRN's biological role in NEC and demonstrate its potential as a therapeutic target for the disease. [ABSTRACT FROM AUTHOR]

Abstract Progranulin (PGRN), which is produced in neurons and microglia, is a neurotrophic and anti-inflammatory glycoprotein. Human loss-of-function mutations cause frontotemporal dementia, and PGRN knockout (KO) mice are a model for dementia. In addition, PGRN KO mice exhibit severe phenotypes in models of traumatic or ischemic central nervous system (CNS) disorders, including traumatic brain injury (TBI). It is unknown whether restoration of progranulin expression in neurons (and not in microglia) might be sufficient to prevent excessive TBI-evoked brain damage. To address this question, we generated mice with Nestin-Cre-driven murine PGRN expression in a PGRN KO line (PGRN-KO NestinGrn ) to rescue PGRN in neurons. PGRN expression analysis in primary CNS cell cultures from naïve mice and in (non-) injured brain tissue from PGRN-KO NestinGrn revealed expression of PGRN in neurons but not in microglia. After experimental TBI, examination of the structural brain damage at 5 days post-injury (dpi) showed that the TBI-induced loss of brain tissue and hippocampal neurons was exacerbated in PGRN-KO Grnflfl mice (PGRN knockout with the mGrn fl-STOP-fl allele, Cre-negative), as expected, whereas the tissue damage in PGRN-KO NestinGrn mice was similar to that in PGRN-WT mice. Analysis of CD68+ immunofluorescent microglia and Cd68 mRNA expression showed that excessive microglial activation was rescued in PGRN-KO NestinGrn mice, and the correlation of brain injury with Cd68 expression suggested that Cd68 was a surrogate marker for excessive brain injury caused by PGRN deficiency. The results show that restoring neuronal PGRN expression was sufficient to rescue the exacerbated neuropathology of TBI caused by PGRN deficiency, even in the absence of microglial PGRN. Hence, endogenous microglial PGRN expression was not essential for the neuroprotective or anti-inflammatory effects of PGRN after TBI in this study. Graphical Abstract

Abstract Backgrounds Progranulin (PGRN) is a growth factor-like molecule with diverse roles in homeostatic and pathogenic processes including the control of immune and inflammatory responses. Pathogenic inflammation is a hallmark of systemic lupus erythematosus (SLE) and elevated serum levels of PGRN has been evaluated as a biomarker of disease activity in SLE. However, the role of PGRN in SLE has not been fully investigated. This study is aimed to determine the potential involvements of PGRN in SLE. Methods Wild type (WT) and PGRN knockout (PGRN-/-) C57BL/6 mice received intraperitoneal injection of pristane for induction of a murine model of SLE. Sera were collected every biweekly and levels of anti-dsDNA antibody, IgG, and inflammatory factors were measured. Mice were sacrificed 5 months later and the renal lesions, as well as the proportions of T cell subtypes in the spleen were analyzed. Results Following exposure to pristane, PGRN-/- mice generated significantly lower levels of anti-dsDNA antibody and IgG relative to WT mice. PGRN-/- mouse kidneys had less IgG and collagen deposition compared with WT mice after pristane injection. Conclusion The results indicate that PGRN participates in inflammatory response and renal damage in pristane induced SLE models, suggesting that PGRN mediates the onset of SLE.

Progranulin (PGRN), a multifunctional growth factor-like protein expressed by a variety of cell types, serves an important function in the physiologic and pathologic processes of fibrotic diseases, including wound healing and the inflammatory response. PGRN was discovered to inhibit pro-inflammation effect by competing with tumor necrosis factor-alpha (TNF-α) binding to TNF receptors. Notably, excessive tissue repair in the development of inflammation causes tissue fibrosis. Previous investigations have indicated the significance of PGRN in regulating inflammatory responses. Recently, multiple studies have shown that PGRN was linked to fibrogenesis, and was considered to monitor the formation of fibrosis in multiple organs, including liver, cardiovascular, lung and skin. This paper is a comprehensive review summarizing our current knowledge of PGRN, from its discovery to the role in fibrosis. This is followed by an in-depth look at the characteristics of PGRN, consisting of its structure, basic function and intracellular signaling. Finally, we will discuss the potential of PGRN in the diagnosis and treatment of fibrosis.

Introduction: Neuroinflammation and microglial activation‐related dendritic injury contribute to the pathogenesis of Autism Spectrum Disorder (ASD). Previous studies show that Progranulin (PGRN) is a growth factor associated with inflammation and synaptic development, but the role of PGRN in autism and the mechanisms underlying changes in PGRN expression remain unclear. Aims: To investigate the impact of PGRN in autism, we stereotactically injected recombinant PGRN into the hippocampus of ASD model rats. Additionally, we explored the possibility that sortilin may be the factor behind the alterations in PGRN by utilizing SORT1 knockdown. Ultimately, we aimed to identify potential targets for the treatment of autism. Results: PGRN could alleviate inflammatory responses, protect neuronal dendritic spines, and ameliorate autism‐like behaviors. Meanwhile, elevated expression of sortilin and decreased levels of PGRN were observed in both ASD patients and rats. Enhanced sortilin levels facilitated PGRN internalization into lysosomes. Notably, suppressing SORT1 expression amplified PGRN levels, lessened microglial activation, and mitigated inflammation, thereby alleviating autism‐like behaviors. Conclusion: Collectively, our findings highlight elevated sortilin levels in ASD rat brains, exacerbating dendrite impairment by affecting PGRN expression. PGRN supplementation and SORT1 knockdown hold potential as therapeutic strategies for ASD. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the role of inflammatory markers and progranulin levels in diagnosing cholecystitis, assessing their potential as diagnostic biomarkers. The research involved 54 patients diagnosed with acute cholecystitis in the emergency department. Routine complete blood count and biochemistry analyses were conducted. Blood samples were obtained, centrifuged, and stored at -80°C. Progranulin levels in sera were assessed using a spectrophotometric method. Statistical analysis was carried out using SPSS v.22.0, revealing significant variances between patients and healthy controls. Acute cholecystitis patients exhibited elevated levels of inflammatory markers (white blood cells, C-reactive protein, procalcitonin) and decreased progranulin levels compared to controls. Progranulin showed a high sensitivity (86.5%) and specificity (87.5%) in diagnosing acute cholecystitis. Other markers had varying sensitivity and specificity values. Inflammatory markers, particularly progranulin, show promise in diagnosing cholecystitis. Evaluating these markers together can enhance diagnostic accuracy. Further studies are needed to validate these findings and explore progranulin's specificity to cholecystitis. [ABSTRACT FROM AUTHOR]

Hydrogels are useful drug release systems and tissue engineering scaffolds. However, synthetic hydrogels often require harsh gelation conditions and can contain toxic by‐products while naturally derived hydrogels can transmit pathogens and in general have poor mechanical properties. Thus, there is a need for a hydrogel that forms under ambient conditions, is non‐toxic, xeno‐free, and has good mechanical properties. A recombinant spider silk protein‐derived hydrogel that rapidly forms at 37 °C is recently developed. The temperature and gelation times are well‐suited for an injectable in situ polymerising hydrogel, as well as a 3D cell culture scaffold. Here, it is shown that the diffusion rate and the mechanical properties can be tuned by changing the protein concentration and that human fetal mesenchymal stem cells encapsulated in the hydrogels show high survival and viability. Furthermore, mixtures of recombinant spider silk proteins and green fluorescent protein (GFP) form gels from which functional GFP is gradually released, indicating that bioactive molecules are easily included in the gels, maintain activity and can diffuse through the gel. Interestingly, encapsulated ARPE‐19 cells are viable and continuously produce the growth factor progranulin, which is detected in the cell culture medium over the study period of 31 days. [ABSTRACT FROM AUTHOR]

Background: Long non-coding RNAs (lncRNAs) play crucial roles in gene regulation and are implicated in neurodegenerative diseases, including frontotemporal dementia (FTD). However, their expression patterns and potential as biomarkers in genetic FTD involving Chromosome 9 Open Reading Frame (C9ORF72), Microtubule Associated Protein Tau (MAPT), and Progranulin (GRN) genes are not well understood. Objective: This study aimed to profile the expression levels of lncRNAs in peripheral blood mononuclear cells collected within the GENetic Frontotemporal dementia Initiative (GENFI). Methods: Fifty-three lncRNAs were analyzed with the OpenArray Custom panel, in 131 patients with mutations in C9ORF72, MAPT, and GRN, including 68 symptomatic mutation carriers (SMC) and 63 presymptomatic mutation carriers (PMC), compared with 40 non-carrier controls (NC). Results: Thirty-eight lncRNAs were detectable; the relative expression of NEAT1 and NORAD was significantly higher in C9ORF72 SMC as compared with NC. GAS5 expression was instead significantly lower in the GRN group versus NC. MAPT carriers showed no significant deregulations. No significant differences were observed in PMC. Disease duration did not correlate with lncRNA expression. Conclusions: NEAT1 and NORAD are upregulated in C9ORF72 SMC and GAS5 levels are downregulated in GRN SMC, underlining lncRNAs' relevance in FTD and their potential for biomarker development. Further validation and mechanistic studies are crucial for clinical implications. [ABSTRACT FROM AUTHOR]

Progranulin (PGRN), a multifunctional growth factor-like protein expressed by a variety of cell types, serves an important function in the physiologic and pathologic processes of fibrotic diseases, including wound healing and the inflammatory response. PGRN was discovered to inhibit pro-inflammation effect by competing with tumor necrosis factor-alpha (TNF- α) binding to TNF receptors. Notably, excessive tissue repair in the development of inflammation causes tissue fibrosis. Previous investigations have indicated the significance of PGRN in regulating inflammatory responses. Recently, multiple studies have shown that PGRN was linked to fibrogenesis, and was considered to monitor the formation of fibrosis in multiple organs, including liver, cardiovascular, lung and skin. This paper is a comprehensive review summarizing our current knowledge of PGRN, from its discovery to the role in fibrosis. This is followed by an in-depth look at the characteristics of PGRN, consisting of its structure, basic function and intracellular signaling. Finally, we will discuss the potential of PGRN in the diagnosis and treatment of fibrosis. Progranulin (PGRN) is a promising biomarker and therapeutic target for fibrotic diseases. PGRN can act both as a pro-fibrotic and as anti-fibrotic factor in several fibrotic diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

Hematopoietic stem cell transplantation can deliver therapeutic proteins to the central nervous system (CNS) through transplant-derived microglia-like cells. However, current conditioning approaches result in low and slow engraftment of transplanted cells in the CNS. Here we optimized a brain conditioning regimen that leads to rapid, robust, and persistent microglia replacement without adverse effects on neurobehavior or hematopoiesis. This regimen combines busulfan myeloablation and six days of Colony-stimulating factor 1 receptor inhibitor PLX3397. Single-cell analyses revealed unappreciated heterogeneity of microglia-like cells with most cells expressing genes characteristic of homeostatic microglia, brain-border-associated macrophages, and unique markers. Cytokine analysis in the CNS showed transient inductions of myeloproliferative and chemoattractant cytokines that help repopulate the microglia niche. Bone marrow transplant of progranulin-deficient mice conditioned with busulfan and PLX3397 restored progranulin in the brain and eyes and normalized brain lipofuscin storage, proteostasis, and lipid metabolism. This study advances our understanding of CNS repopulation by hematopoietic-derived cells and demonstrates its therapeutic potential for treating progranulin-dependent neurodegeneration. Progranulin deficiency causes untreatable neurodegenerative diseases. Here, the authors show that hematopoietic stem cell transplantation and optimized brain conditioning correct the disease phenotype in progranulin-deficient mice. [ABSTRACT FROM AUTHOR]

In systemic sclerosis (SSc), fibrosis of the myocardium along with ongoing autoimmune inflammation can alter the electric function of the cardiac myocytes, which may increase the risk for ventricular arrhythmias and sudden cardiac death. We analyzed the electrocardiographic (ECG) variables describing ventricular repolarization such as QT interval, QT dispersion (QTd), T wave peak-to-end interval (Tpe), and arrhythmogeneity index (AIX) of 26 patients with SSc and 36 healthy controls. Furthermore, echocardiographic and laboratory parameters were examined, with a focus on inflammatory proteins like C-reactive ptotein (CRP), soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), and progranulin (PGRN). The CRP, sICAM-1, and sVCAM-1 levels were positively correlated with the length of the QT interval. Although the serum PGRN levels were not increased in the SSc group compared to the controls, in SSc patients, the PGRN levels were positively correlated with the QT interval and the AIX. According to our results, we conclude that there may be a potential association between autoimmune inflammation and the risk for ventricular arrhythmias in patients with SSc. We emphasize that the measurement of laboratory parameters of inflammatory activity including CRP, PGRN, sVCAM-1, and sICAM-1 could be helpful in the prediction of sudden cardiac death in patients with SSc. [ABSTRACT FROM AUTHOR]

Problem: To explore the clinical utility of nine inflammatory immune‐, adhesion‐, and extracellular matrix‐related mediators in the plasma for predicting intraamniotic inflammation and/or microbial invasion of the amniotic cavity (IAI/MIAC) and composite neonatal morbidity and/or mortality (CNMM) in women with preterm premature rupture of membranes (PPROM) when used alone or in combination with conventional blood‐, ultrasound‐, and clinical‐based factors. Methods of Study: This retrospective cohort comprised 173 singleton pregnant women with PPROM (24 + 0 – 33 + 6 weeks), who underwent amniocentesis. Amniotic fluid was cultured for microorganisms and assayed for IL‐6 levels. Plasma levels of AFP, CXCL14, E‐selectin, Gal‐3BP, kallistatin, progranulin, P‐selectin, TGFBI, and VDBP were determined by ELISA. Ultrasonographic cervical length (CL) and neutrophil‐to‐lymphocyte ratio (NLR) were measured. Results: Multivariate logistic regression analyses revealed significant associations between (i) decreased plasma kallistatin levels and IAI/MIAC and (ii) decreased plasma progranulin levels and increased CNMM risk after adjusting for baseline variables (e.g., gestational age at sampling [or delivery] and parity). Using stepwise regression analysis, noninvasive prediction models for IAI/MIAC and CNMM risks were developed, which included plasma progranulin levels, NLR, CL, and gestational age at sampling, and provided a good prediction of the corresponding endpoints (area under the curve: 0.79 and 0.87, respectively). Conclusions: Kallistatin and progranulin are potentially valuable plasma biomarkers for predicting IAI/MIAC and CNMM in women with PPROM. Particularly, the combination of these plasma biomarkers with conventional blood‐, ultrasound‐, and clinical‐based factors can significantly support the diagnosis of IAI/MIAC and CNMM. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Frontotemporal lobar degeneration (FTLD) encompasses behavioral variant frontotemporal dementia (bvFTD), progressive supranuclear palsy, corticobasal syndrome/degeneration, and primary progressive aphasias (PPAs). We cross‐validated fluid biomarkers and neuroimaging. METHODS: Seven fluid biomarkers from cerebrospinal fluid and serum were related to atrophy in 428 participants including these FTLD subtypes, logopenic variant PPA (lvPPA), Alzheimer's disease (AD), and healthy subjects. Atrophy was assessed by structural magnetic resonance imaging and atlas‐based volumetry. RESULTS: FTLD subtypes, lvPPA, and AD showed specific profiles for neurofilament light chain, phosphorylated heavy chain, tau, phospho‐tau, amyloid beta1‐42 from serum/cerebrospinal fluid, and brain atrophy. Neurofilaments related to regional atrophy in bvFTD, whereas progranulin was associated with atrophy in semantic variant PPA. Ubiquitin showed no effects. DISCUSSION: Results specify biomarker and atrophy patterns in FTLD and AD supporting differential diagnosis. They identify neurofilaments and progranulin in interaction with structural imaging as promising candidates for monitoring disease progression and therapy. Highlights: Study cross‐validated neuroimaging and fluid biomarkers in dementia.Five kinds of frontotemporal lobar degeneration and two variants of Alzheimer's disease.Study identifies disease‐specific fluid biomarker and atrophy profiles.Fluid biomarkers and atrophy interact in a disease‐specific way.Neurofilaments and progranulin are proposed as biomarkers for diagnosis and therapy. [ABSTRACT FROM AUTHOR]

Background and Objectives: Diabetes is a significant health problem, prompting the search for new therapeutic strategies. Recently, researchers have focused on identifying novel markers for the progression of this condition. It is well established that adipokines, such as progranulin and vaspin, play crucial roles in regulating lipid and carbohydrate metabolism. Materials and Methods: This single-center cross-sectional study aimed to assess serum progranulin and vaspin levels in 80 children diagnosed with type 1 diabetes (T1D) and to examine their correlation with body mass index (BMI), glycated hemoglobin, and lipid profile. The cohort included 40 children newly diagnosed with diabetes, 40 children with long-term diabetes (20 well-controlled and 20 poorly controlled), and 14 non-diabetic children as a control group. Progranulin and vaspin levels were determined using a sandwich enzyme-linked immunosorbent assay. Results: There were no significant differences in the progranulin and vaspin concentrations in the studied groups (p = 0.246 and p = 0.095, respectively). No statistically significant differences were noted in the levels of both adipokines among boys and girls within the T1D, well-controlled T1D, and poorly controlled T1D groups. We did not find any differences in the progranulin and vaspin levels among all children with T1D and healthy controls when divided based on BMI percentiles. A negative correlation was observed between progranulin concentration and the age of children in the T1D, well-controlled T1D, and healthy groups. Furthermore, progranulin correlated negatively with BMI among children with T1D. In contrast, vaspin concentration correlated positively with age among healthy children. Conclusions: Our study provides novel insights into the status of progranulin and vaspin among pediatric participants with varying levels of type 1 diabetes control. However, further research involving larger patient cohorts and different stages of sexual maturation is warranted. [ABSTRACT FROM AUTHOR]

Background: Intensive care unit admissions are largely attributed to sepsis in pediatrics. It is essential to diagnose an infection correctly and monitor it closely to optimize treatment and outcomes. Aim: This research was conducted to estimate the diagnostic utility of serum progranulin in pediatric sepsis. Patients and methods: This case-control study included 50 pediatric sepsis patients and 40 healthy matched controls. A peripheral blood sample was taken from the patients and controls then progranulin levels were measured using ELISA. Results: Serum progranulin values were significantly greater in pediatric sepsis patients than in controls (median 180.15 vs. 96.0 ng/ml, respectively: Mann-Whitney p < 0.001). Serum progranulin had good diagnostic power and was the best of laboratory parameters in the diagnosis of pediatric sepsis after CRP with ROC area under the curve (AUC) = 0.998. Using a cutoff value of 116.3 ng/ml PGRN had a sensitivity of 86.0% and a specificity of 100% with a positive predictive value of 100% and a negative predictive value of 85.1%. Serum progranulin levels were positively correlated with body weight and CRP levels and negatively correlated with platelets and hemoglobin levels. Progranulin levels in survivors were not statistically different from those in non-survivors. Conclusions and Recommendations: Serum progranulin may be a good biomarker for sepsis diagnosis in pediatrics. [ABSTRACT FROM AUTHOR]

Enhanced mortality, relapse rates, and increased prevalence of Clostridioides difficile infection (CDI) emphasize the need for better therapies and management approaches. Modulating host immune response to ameliorate CDI-associated immunopathology may provide new advantages to currently inadequate antibiotic therapies. Here, we identified progranulin (PGRN) as an important immune target upregulated in response to CDI. PGRN-deficient mice displayed dramatically higher mortality and aggravated epithelial barrier disruption compared with wild type (WT) mice after CDI despite equivalent levels of bacterial burden or toxin in the large intestine. Mechanistically, PGRN protection was mediated by IL-22 production from CD4+ T helper cells, as demonstrated by a decrease in colonic IL-22-producing CD4+ T helper cells in the intestine of PGRN-deficient mice upon CDI and a boost of IL-22-producing CD4+ T helper cells activated by PGRN ex vivo. Clinical evidence suggests that CDI patients had significantly higher serum levels of PGRN compared with healthy controls, which was significantly and positively correlated with IL-22. Our findings thus indicate a critical role for PGRN-promoted CD4+ T cell IL-22 production in shaping gut immunity and reestablishing the intestinal barrier during CDI. As an alternative to pathogen-targeted therapy, this study may provide a new host-directed therapeutic strategy to attenuate severe, refractory CDI.

Objective: To investigate the relationship between serum high mobility group protein 1 (HMGB1), progranulin (PGRN) and natural killer (NK) cell subsets and interstitial lung disease (ILD) in patients with Sjogren's syndrome (SS). Methods: 89 patients with SS admitted to the Zibo 148 Hospital from September 2018 to December 2023 were selected as observation group, and 80 healthy individuals in same period were selected as control group. The correlation between serum HMGB1, PGRN and NK cell subsets in SS patients were analyzed by Pearson correlation analysis. The risk factors of ILD in SS patients were analyzed by multivariate Logistic regression analysis. Results: Serum HMGB1 and PGRN were negatively correlated with CD3- CD16+ CD56+ NK count in SS patients (P<0. 001). The levels of HMGB1 and PGRN in ILD group were higher than those in non-ILD group, and the CD3- CD16+ CD56+ NK count was lower than that in non-ILD group (P<0.05). Multivariate Logistic analysis showed that, advanced age, high HMGB1, and high PGRN were risk factors for ILD in SS patients, and elevated CD3- CD16+ CD56+ NK was a protective factor (all P<0.05). Conclusion: Serum HMGB1 and PGRN are increased in SS patients, which are negatively correlated with NK cell subsets. Elevated serum HMGB1, PGRN and decreased NK cell subsets are the influencing factors of ILD in SS patients. [ABSTRACT FROM AUTHOR]

Abstract Loss-of-function mutations in the progranulin (GRN) gene are an autosomal dominant cause of Frontotemporal Dementia (FTD). These mutations typically result in haploinsufficiency of the progranulin protein. Grn +/– mice provide a model for progranulin haploinsufficiency and develop FTD-like behavioral abnormalities by 9–10 months of age. In previous work, we demonstrated that Grn +/– mice develop a low dominance phenotype in the tube test that is associated with reduced dendritic arborization of layer II/III pyramidal neurons in the prelimbic region of the medial prefrontal cortex (mPFC), a region key for social dominance behavior in the tube test assay. In this study, we investigated whether progranulin haploinsufficiency induced changes in dendritic spine density and morphology. Individual layer II/III pyramidal neurons in the prelimbic mPFC of 9–10 month old wild-type or Grn +/– mice were targeted for iontophoretic microinjection of fluorescent dye, followed by high-resolution confocal microscopy and 3D reconstruction for morphometry analysis. Dendritic spine density in Grn +/– mice was comparable to wild-type littermates, but the apical dendrites in Grn +/– mice had a shift in the proportion of spine types, with fewer stubby spines and more thin spines. Additionally, apical dendrites of Grn +/– mice had longer spines and smaller thin spine head diameter in comparison to wild-type littermates. These changes in spine morphology may contribute to altered circuit-level activity and social dominance deficits in Grn +/– mice.

This study aimed to investigate the role of inflammatory markers and progranulin levels in diagnosing cholecystitis, assessing their potential as diagnostic biomarkers. The research involved 54 patients diagnosed with acute cholecystitis in the emergency department. Routine complete blood count and biochemistry analyses were conducted. Blood samples were obtained, centrifuged, and stored at -80°C. Progranulin levels in sera were assessed using a spectrophotometric method. Statistical analysis was carried out using SPSS v.22.0, revealing significant variances between patients and healthy controls. Acute cholecystitis patients exhibited elevated levels of inflammatory markers (white blood cells, C-reactive protein, procalcitonin) and decreased progranulin levels compared to controls. Progranulin showed a high sensitivity (86.5%) and specificity (87.5%) in diagnosing acute cholecystitis. Other markers had varying sensitivity and specificity values. Inflammatory markers, particularly progranulin, show promise in diagnosing cholecystitis. Evaluating these markers together can enhance diagnostic accuracy. Further studies are needed to validate these findings and explore progranulin's specificity to cholecystitis. [Med-Science 2024; 13(3.000): 649-53]

Objectives: This study aimed to investigate the impact of two different aerobic exercise programs on the Body Mass Index (BMI) and progranulin (PGRN) levels of overweight or obese female students.Methods: In this quasi-experimental study, 36 overweight or obese female students from Kashan University of Medical Sciences and Islamic Azad University volunteered to participate. They were randomly divided into three groups: two groups underwent progressively increasing interval or continuous aerobic exercise programs, while the third group served as a control. The exercise programs lasted for 8 consecutive weeks, with blood samples collected before and after the intervention. Progranulin levels were measured using the ELISA technique with Human PGRN, and BMI was assessed at the beginning and end of the program.Results: The results of a one-way ANOVA test showed a significant decrease in progranulin levels (P=0.00) and BMI in both exercise groups compared to the control group (P=0.029).Conclusion: Both interval and continuous aerobic exercise programs were effective in reducing circulating progranulin levels and BMI in overweight or obese female college students. The exercise interventions led to a significant decrease in both variables. Further research is warranted to explore the effects of different aerobic exercise protocols on BMI and progranulin levels in normal adults.

Abstract The present study aimed to examine the effects of progranulin and omentin on basic ovarian cell functions. For this purpose, we investigated the effects of the addition of progranulin and omentin (0, 0.1, 1, or 10 ng/ml) on the viability, proliferation, apoptosis and steroidogenesis of cultured rabbit ovarian granulosa cells. To determine the importance of the interrelationships between granulosa cells and theca cells, we compared the influence of progranulin and omentin on progesterone and estradiol release in cultured granulosa cells and ovarian fragments containing both granulosa cells and theca cells. Cell viability, proliferation, cytoplasmic apoptosis and release of progesterone and estradiol were measured by Cell Counting Kit-8 (CCK-8), BrdU incorporation, cell death detection, and ELISA. Both progranulin and omentin increased granulosa cell viability and proliferation and decreased apoptosis. Progranulin increased progesterone release by granulosa cells but reduced progesterone output by ovarian fragments. Progranulin decreased estradiol release by granulosa cells but increased it in ovarian fragments. Omentin reduced progesterone release in both models. Omentin reduced estradiol release by granulosa cells but promoted this release in ovarian fragments. The present observations are the first to demonstrate that progranulin and omentin can be direct regulators of basic ovarian cell functions. Furthermore, the differences in the effects of these adipokines on steroidogenesis via granulosa and ovarian fragments indicate that these peptides could target both granulosa and theca cells.

Estrogen deficiency is considered the most important cause of postmenopausal osteoporosis. However, the underlying mechanism is still not completely understood. In this study, progranulin (PGRN) was isolated as a key regulator of bone mineral density in postmenopausal women through high throughput proteomics screening. In addition, PGRN-deficient mice exhibited significantly lower bone mass than their littermates in an ovariectomy-induced osteoporosis model. Furthermore, estrogen-mediated inhibition of osteoclastogenesis and bone resorption as well as its protection against ovariectomy-induced bone loss largely depended on PGRN. Mechanistic studies revealed the existence of a positive feedback regulatory loop between PGRN and estrogen signaling. In addition, loss of PGRN led to the reduction of estrogen receptor α, the important estrogen receptor involved in estrogen regulation of osteoporosis, through enhancing its degradation via K48-linked ubiquitination. These findings not only provide a previously unrecognized interplay between PGRN and estrogen signaling in regulating osteoclastogenesis and osteoporosis but may also present a new therapeutic approach for the prevention and treatment of postmenopausal osteoporosis by targeting PGRN/estrogen receptor α.

Loss of function progranulin (GRN) mutations are a major autosomal dominant cause of frontotemporal dementia (FTD). Patients with FTD due to GRN mutations (FTD-GRN) develop frontotemporal lobar degeneration with TDP-43 pathology type A (FTLD-TDP type A) and exhibit elevated levels of lysosomal proteins and storage material in frontal cortex, perhaps indicating lysosomal dysfunction as a mechanism of disease. To investigate whether patients with sporadic FTLD exhibit similar signs of lysosomal dysfunction, we compared lysosomal protein levels, transcript levels, and storage material in patients with FTD-GRN or sporadic FTLD-TDP type A. We analyzed samples from frontal cortex, a degenerated brain region, and occipital cortex, a relatively spared brain region. In frontal cortex, patients with sporadic FTLD-TDP type A exhibited similar increases in lysosomal protein levels, transcript levels, and storage material as patients with FTD-GRN. In occipital cortex of both patient groups, most lysosomal measures did not differ from controls. Frontal cortex from a transgenic mouse model of TDP-opathy had similar increases in cathepsin D and lysosomal storage material, showing that TDP-opathy and neurodegeneration can drive these changes independently of progranulin. To investigate these changes in additional FTLD subtypes, we analyzed frontal cortical samples from patients with sporadic FTLD-TDP type C or Pick's disease, an FTLD-tau subtype. All sporadic FTLD groups had similar increases in cathepsin D activity, lysosomal membrane proteins, and storage material as FTD-GRN patients. However, patients with FTLD-TDP type C or Pick's disease did not have similar increases in lysosomal transcripts as patients with FTD-GRN or sporadic FTLD-TDP type A. Based on these data, accumulation of lysosomal proteins and storage material may be a common aspect of end-stage FTLD. However, the unique changes in gene expression in patients with FTD-GRN or sporadic FTLD-TDP type A may indicate distinct underlying lysosomal changes among FTLD subtypes.

Progranulin (PGRN) haploinsufficiency is a major risk factor for frontotemporal lobar degeneration with TAR DNA-binding protein 43 (TDP-43) pathology (FTLD-GRN). Multiple therapeutic strategies are in clinical development to restore PGRN in the CNS, including gene therapy. However, a limitation of current gene therapy approaches aimed to alleviate FTLD-associated pathologies may be their inefficient brain exposure and biodistribution. We therefore developed an adeno-associated virus (AAV) targeting the liver (L) to achieve sustained peripheral expression of a transferrin receptor (TfR) binding, brain-penetrant (b) PGRN variant [AAV(L):bPGRN] in two mouse models of FTLD-GRN, namely, Grn knockout and GrnxTmem106b double knockout mice. This therapeutic strategy avoids potential safety and biodistribution issues of CNS-administered AAVs and maintains sustained concentrations of PGRN in the brain after a single dose. AAV(L):bPGRN treatment reduced several FTLD-GRN–associated pathologies including severe motor function deficits, aberrant TDP-43 phosphorylation, dysfunctional protein degradation, lipid metabolism, gliosis, and neurodegeneration in the brain. The potential translatability of our findings was tested in an in vitro model using cocultured human induced pluripotent stem cell (hiPSC)–derived microglia lacking PGRN and TMEM106B and wild-type hiPSC-derived neurons. As in mice, aberrant TDP-43, lysosomal dysfunction, and neuronal loss were ameliorated after treatment with exogenous TfR-binding protein transport vehicle fused to PGRN (PTV:PGRN). Together, our studies suggest that peripherally administered brain-penetrant PGRN replacement strategies ameliorate FTLD-GRN relevant phenotypes including TDP-43 pathology, neurodegeneration, and behavioral deficits. Our data provide preclinical proof of concept for the use of this AAV platform for treatment of FTLD-GRN and potentially other CNS disorders. Editor's summary: The restoration of brain progranulin holds promise for the treatment of frontotemporal lobar degeneration with GRN loss-of-function mutations (FTLD-GRN). However, delivering therapeutics to the brain remains a challenge. Here, Reich et al. developed an adeno-associated virus (AAV) vector for the sustained expression of a brain-penetrant variant of human progranulin in the liver. Using two mouse models of FTLD-GRN, the authors show that a single intravenous injection of this AAV achieved sustained progranulin concentrations in the brain for up to 31 weeks and could rescue different FTLD-GRN associated pathologies, highlighting the translational potential of this approach. —Daniela Neuhofer [ABSTRACT FROM AUTHOR]

Back ground: Chronic obstructive pulmonary disease, or COPD, is an inflammatory chronic illness of the parenchyma and/or airways that is typically accompanied by increasing, irreversible dyspnea, coughing, sputum production, and/or exacerbations of respiratory symptoms. The pathological process of COPD includes bronchitis and/or emphysema; inflammation in the lungs has systemic effects as well. The most frequent causes of COPD are indoor and occupational pollution. Progranulin, or PGRN, is a precursor of pleiotropic glycosylated protein that plays a major role in wound healing, angiogenesis, neoplasia, cell development, the cell cycle, inflammation, and the modification of the autoimmune process. It is highly prevalent in a variety of cell types, including respiratory epithelial cells. Objective: The aim is to study relationship between serum level of PGRN and inflammatory markers in COPD patients. Material and method: A case control study composed of 40 patients with COPD and 45 controls, demographic characteristic, blood investigation include CRP-titer, WBC and plasma PGRN were measured and made comparison of data in cases with controls, data collected were statically analysis by SPSS. Result: The study showed that, there was no significant correlation between serum progranulin level, WBC and C-Reactive Protein titer in COPD patients (P value >0.05). Conclusions: It was concluded that PGRN level in COPD patients don't correlate with CRP titer level or with WBC. [ABSTRACT FROM AUTHOR]

Background: Tumor microenvironment actually reduces antitumor effect against the immune attack by exclusion of CD8+T cells. Progranulin (PGRN) is a multifunctional growth factor with significant pathological effects in multiple tumors; however, its role in immunity evasion of breast cancer (BCa) is not completely understood. Methods: We depleted GRN (PGRN gene) genetically in mice or specifically in PY8119 murine BCa cell line, and mouse models of orthotopic or subcutaneous transplantation were used. Chimeric mice-deficient of PGRN (Grn−/−) in bone marrow (BM) compartment was also generated. Association of PGRN expression with chemokine production or BCa development was investigated by histological and immunological assays. Results: We found PGRN was involved in exhaustion of cytotoxic CD8+T cell in BCa with the increasing expressions of M2 markers and intercellular cell adhesion molecule-1 (ICAM-1) on macrophages. Specifically, ablation of PGRN in PY8119 cells reduced tumor burden, accompanied by the infiltrating of cytotoxic CD8+T cells into tumor nests. Moreover, our result revealed that blockade of PD-1 in PGRN-depleted tumors exhibited better antitumor effect in vivo and significantly decreased tumor burden. Conclusion: These findings suggest that inhibition of PGRN may act as a potential immune-therapeutic strategy by recovering infiltration of CD8+T cell in BCa tissue and thereby enhancing the response to anti-PD-1 therapy. [ABSTRACT FROM AUTHOR]

The present study aimed to examine the effects of progranulin and omentin on basic ovarian cell functions. For this purpose, we investigated the effects of the addition of progranulin and omentin (0, 0.1, 1, or 10 ng/ml) on the viability, proliferation, apoptosis and steroidogenesis of cultured rabbit ovarian granulosa cells. To determine the importance of the interrelationships between granulosa cells and theca cells, we compared the influence of progranulin and omentin on progesterone and estradiol release in cultured granulosa cells and ovarian fragments containing both granulosa cells and theca cells. Cell viability, proliferation, cytoplasmic apoptosis and release of progesterone and estradiol were measured by Cell Counting Kit-8 (CCK-8), BrdU incorporation, cell death detection, and ELISA. Both progranulin and omentin increased granulosa cell viability and proliferation and decreased apoptosis. Progranulin increased progesterone release by granulosa cells but reduced progesterone output by ovarian fragments. Progranulin decreased estradiol release by granulosa cells but increased it in ovarian fragments. Omentin reduced progesterone release in both models. Omentin reduced estradiol release by granulosa cells but promoted this release in ovarian fragments. The present observations are the first to demonstrate that progranulin and omentin can be direct regulators of basic ovarian cell functions. Furthermore, the differences in the effects of these adipokines on steroidogenesis via granulosa and ovarian fragments indicate that these peptides could target both granulosa and theca cells. [ABSTRACT FROM AUTHOR]

Progranulin (PGRN), encoded by the GRN gene in humans, was originally isolated as a secreted growth factor that implicates in a multitude of processes ranging from regulation of tumorigenesis, inflammation to neural proliferation. Compelling evidence indicating that GRN mutation can lead to various common neuronal degenerative diseases and rare lysosomal storage diseases. These findings have unveiled a critical role for PGRN as a lysosomal protein in maintaining lysosomal function. The phenotypic spectrum of PGRN imbalance has expanded to encompass a broad spectrum of diseases, including autoimmune diseases, metabolic, musculoskeletal and cardiovascular diseases. These diseases collectively referred to as Progranulinopathy- a term encompasses the wide spectrum of disorders influenced by PGRN imbalance. Unlike its known extracellular function as a growth factor-like molecule associated with multiple membrane receptors, PGRN also serves as an intracellular co-chaperone engaged in the folding and traffic of its associated proteins, particularly the lysosomal hydrolases. This chaperone activity is required for PGRN to exert its diverse functions across a broad range of diseases, encompassing both the central nervous system and peripheral systems. In this comprehensive review, we present an update of the emerging role of PGRN in Progranulinopathy, with special focus on elucidating the intricate interplay between PGRN and a diverse array of proteins at various levels, ranging from extracellular fluids and intracellular components, as well as various pathophysiological processes involved. This review seeks to offer a comprehensive grasp of PGRN's diverse functions, aiming to unveil intricate mechanisms behind Progranulinopathy and open doors for future research endeavors. [Display omitted] • Progranulin is involved in processes ranging from tumorigenesis and inflammation to neural proliferation. • Mutations in the GRN gene can result in various neuronal degenerative diseases and rare lysosomal storage disorders. • The range of conditions and diseases stemming from PGRN imbalance collectively termed as Progranulinopathy. • Beyond recognized role as an extracellular growth factor-like molecule, PGRN also operates as an intracellular co-chaperone. • This review delves into the complex interplay between PGRN and an assorted array of proteins across different tiers. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the impact of two different aerobic exercise programs on the Body Mass Index (BMI) and progranulin (PGRN) levels of overweight or obese female students. Methods: In this quasi-experimental study, 36 overweight or obese female students from Kashan University of Medical Sciences and Islamic Azad University volunteered to participate. They were randomly divided into three groups: two groups underwent progressively increasing interval or continuous aerobic exercise programs, while the third group served as a control. The exercise programs lasted for 8 consecutive weeks, with blood samples collected before and after the intervention. Progranulin levels were measured using the ELISA technique with Human PGRN, and BMI was assessed at the beginning and end of the program. Results: The results of a one-way ANOVA test showed a significant decrease in progranulin levels (P=0.00) and BMI in both exercise groups compared to the control group (P=0.029). Conclusion: Both interval and continuous aerobic exercise programs were effective in reducing circulating progranulin levels and BMI in overweight or obese female college students. The exercise interventions led to a significant decrease in both variables. Further research is warranted to explore the effects of different aerobic exercise protocols on BMI and progranulin levels in normal adults. [ABSTRACT FROM AUTHOR]

INTRODUCTION: We aimed to expand the range of the frontotemporal dementia (FTD) phenotypes assessed by the Clinical Dementia Rating Dementia Staging Instrument plus National Alzheimer's Coordinating Center Behavior and Language Domains (CDR plus NACC FTLD). METHODS: Neuropsychiatric and motor domains were added to the standard CDR plus NACC FTLD generating a new CDR plus NACC FTLD‐NM scale. This was assessed in 522 mutation carriers and 310 mutation‐negative controls from the Genetic Frontotemporal dementia Initiative (GENFI). RESULTS: The new scale led to higher global severity scores than the CDR plus NACC FTLD: 1.4% of participants were now considered prodromal rather than asymptomatic, while 1.3% were now considered symptomatic rather than asymptomatic or prodromal. No participants with a clinical diagnosis of an FTD spectrum disorder were classified as asymptomatic using the new scales. DISCUSSION: Adding new domains to the CDR plus NACC FTLD leads to a scale that encompasses the wider phenotypic spectrum of FTD with further work needed to validate its use more widely. Highlights: The new Clinical Dementia Rating Dementia Staging Instrument plus National Alzheimer's Coordinating Center Behavior and Language Domains neuropsychiatric and motor (CDR plus NACC FTLD‐NM) rating scale was significantly positively correlated with the original CDR plus NACC FTLD and negatively correlated with the FTD Rating Scale (FRS).No participants with a clinical diagnosis in the frontotemporal dementia spectrum were classified as asymptomatic with the new CDR plus NACC FTLD‐NM rating scale.Individuals had higher global severity scores with the addition of the neuropsychiatric and motor domains.A receiver operating characteristic analysis of symptomatic diagnosis showed nominally higher areas under the curve for the new scales. [ABSTRACT FROM AUTHOR]

IntroductionProgranulin (PGRN) is a holoprotein that is internalized and taken to the lysosome where it is processed to individual granulins (GRNs). PGRN is critical for successful aging, and insufficient levels of PGRN are associated with increased risk for developing neurodegenerative diseases like AD, PD, and FTD. A unifying feature among these diseases is dysregulation of peripheral immune cell populations. However, considerable gaps exist in our understanding of the function(s) of PGRN/GRNs in immune cells and their role in regulating central-peripheral neuroimmune crosstalk. One of the most upregulated genes and proteins in humans with GRN haploinsufficiency and in aged Grn knock-out (KO) mice is glycoprotein non-metastatic B (GPNMB) but its normal role within the context of immune crosstalk has not been elucidated.MethodsTo address this gap, peritoneal macrophages (pMacs) from 5-to-6-month old WT and Grn KO mice were assessed for Gpnmb expression and stimulation-dependent cytokine release in the presence or absence of the Gpnmb extracellular domain (ECD). Cellular localization, as well as inhibition of, the microphthalmia-associated transcription factor (MITF) was assessed to determine its mechanistic role in Gpnmb overexpression in Grn KO pMacs.ResultsWe observed an increase in GPNMB protein and mRNA as a result of insufficient progranulin in peripheral immune cells at a very early age relative to previous reports on the brain. Stimulation-dependent cytokine release was decreased in the media of Grn KO pMacs relative to WT controls; a phenotype that could be mimicked in WT pMacs with the addition og GPNMB ECD. We also found that MITF is dysregulated in Grn KO pMacs; however, its nuclear translocation and activity are not required to rescue the immune dysregulation of Grn KO macrophages, suggesting redundancy in the system.DiscussionThese findings highlight the fact that knowledge of early-stage disease mechanism(s) in peripheral populations may inform treatment strategies to delay disease progression at an early, prodromal timepoint prior to development of neuroinflammation and CNS pathology.

Abstract Background Pathogenic heterozygous mutations in the progranulin gene (GRN) are a key cause of frontotemporal dementia (FTD), leading to significantly reduced biofluid concentrations of the progranulin protein (PGRN). This has led to a number of ongoing therapeutic trials aiming to treat this form of FTD by increasing PGRN levels in mutation carriers. However, we currently lack a complete understanding of factors that affect PGRN levels and potential variation in measurement methods. Here, we aimed to address this gap in knowledge by systematically reviewing published literature on biofluid PGRN concentrations. Methods Published data including biofluid PGRN concentration, age, sex, diagnosis and GRN mutation were collected for 7071 individuals from 75 publications. The majority of analyses (72%) had focused on plasma PGRN concentrations, with many of these (56%) measured with a single assay type (Adipogen) and so the influence of mutation type, age at onset, sex, and diagnosis were investigated in this subset of the data. Results We established a plasma PGRN concentration cut-off between pathogenic mutation carriers and non-carriers of 74.8 ng/mL using the Adipogen assay based on 3301 individuals, with a CSF concentration cut-off of 3.43 ng/mL. Plasma PGRN concentration varied by GRN mutation type as well as by clinical diagnosis in those without a GRN mutation. Plasma PGRN concentration was significantly higher in women than men in GRN mutation carriers (p = 0.007) with a trend in non-carriers (p = 0.062), and there was a significant but weak positive correlation with age in both GRN mutation carriers and non-carriers. No significant association was seen with weight or with TMEM106B rs1990622 genotype. However, higher plasma PGRN levels were seen in those with the GRN rs5848 CC genotype in both GRN mutation carriers and non-carriers. Conclusions These results further support the usefulness of PGRN concentration for the identification of the large majority of pathogenic mutations in the GRN gene. Furthermore, these results highlight the importance of considering additional factors, such as mutation type, sex and age when interpreting PGRN concentrations. This will be particularly important as we enter the era of trials for progranulin-associated FTD.