Abnormal Protein Research Articles

Embryonic Lethal Abnormal Visual-Like Protein 1 Aggravates Caerulein-Induced AR42J Cell Injury and Macrophage M1 Polarization to Accelerate Acute Pancreatitis by Upregulating TRAF6.

Tumor necrosis factor receptor-associated factor 6 (TRAF6) has been found to promote the progression of acute pancreatitis (AP). However, its underlying molecular mechanisms in AP need to be further revealed. Caerulein-induced AR42J cells were used to construct AP cell models. Cell viability and apoptosis were measured by Cell Counting Kit 8 assay and flow cytometry. Levels of inflammatory factors and oxidative stress-related markers were assessed. The medium of AR42J cells was collected for coculturing RAW264.7 cells. Macrophage marker CD86+ cell rates were checked with flow cytometry. The levels of TRAF6, embryonic lethal abnormal visual-like protein 1 (ELAVL1), and inducible nitric oxide synthase (iNOS) were examined by Western blot or quantitative real-time polymerase chain reaction. RNA immunoprecipitation assay was performed to evaluate the interaction between ELAVL1 and TRAF6. TRAF6 mRNA stability was tested using actinomycin D treatment. Caerulein treatment suppressed viability, induced AR42J cell apoptosis, inflammation, oxidative stress, and accelerated macrophage M1 polarization. TRAF6 downregulation could alleviate caerulein-induced AR42J cell injury and macrophage M1 polarization. ELAVL1 interacted with TRAF6 to stabilize its expression. Meanwhile, ELAVL1 knockdown relieved caerulein-induced AR42J cell injury and macrophage M1 polarization, while these effects were abolished by TRAF6 overexpression. TRAF6, stabilized by ELAVL1, promoted caerulein-induced AR42J cell injury and macrophage M1 polarization, suggesting that it might accelerate AP9 progression.

Patterns of tau, amyloid and synuclein pathology in ageing, Alzheimer's disease and synucleinopathies.

Alzheimer's disease (AD) is neuropathologically defined by deposits of misfolded hyperphosphorylated tau (HP-tau) and β-amyloid. Lewy body (LB) dementia, which includes dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), is characterised pathologically by α-synuclein aggregates. HP-tau and β-amyloid can also occur as copathologies in LB dementia, and a diagnosis mixedAD/DLB can be made if present in sufficient quantities. We hypothesised the spread of these abnormal proteins selectively affects vulnerable areas, resulting in pathologic regional covariance that differentially associates with pre-mortem clinical characteristics. Our aims were to map regional quantitative pathology (HP-tau, β-amyloid, α-synuclein) and investigate the spatial distributions from tissue microarray (TMA) post-mortem samples across healthy aging, AD and LB dementia. The study involved 159 clinico-pathologically diagnosed human post-mortem brains (48 controls, 47 AD, 25 DLB, 20 mixedAD/DLB, 19 PDD). The burden of HP-tau, β-amyloid and α-synuclein was quantitatively assessed in cortical and subcortical areas. Principal components (PC) analysis was applied across all cases to determine the pattern nature of HP-tau, β-amyloid and α-synuclein. Further analyses explored the relationships of these pathological patterns with cognitive and symptom variables. Cortical (tauPC1) and temporolimbic (tauPC2) patterns were observed for HP-tau. For β-amyloid, a cortical-subcortical pattern (amylPC1) was identified. For α-synuclein, four patterns emerged: 'posterior temporal - occipital (synPC1)', 'anterior temporal-frontal (synPC2)', 'parieto-cingulate-insula (synPC3)', and 'frontostriatal-amygdala (synPC4)'. Distinct synPC scores were apparent among DLB, mixedAD/DLB and PDD, and may relate to different spreading patterns of α-synuclein pathology. In dementia, cognitive measures correlated with tauPC1, tauPC2 and amylPC1 pattern scores (P≤0.02), whereas such variables did not relate to α-synuclein parameters in these or combined LB dementia cases. Mediation analysis then revealed that in the presence of amylPC1, tauPC1 had a direct effect on global cognition in dementia (n=65, P=0.04), while tauPC1 mediated the relationship between amylPC1 and cognition through the indirect pathway (amylPC1→ tauPC1 → global cognition) (P<0.05). Lastly, in synucleinopathies, synPC1 and synPC4 pattern scores were associated with visual hallucinations and motor impairment, respectively (P=0.02). In conclusion, distinct patterns of α-synuclein pathology were apparent in LB dementia, which could explain some of the disease heterogeneity and differing spreading patterns among these conditions. Visual hallucinations and motor severity were associated with specific α-synuclein topographies in LB dementia that may be important to the clinical phenotype, and could, after necessary testing/validation, be integrated into semi-quantitative routine pathological assessment.

The Possible Roles of Glucosamine-6-Phosphate Deaminases in Ammonium Metabolism in Cancer

Nearly 5% of the glucose-6-phosphate (Glc6P) in cells is diverted into the hexosamine biosynthetic pathway (HBP) to synthesize glucosamine-6-phosphate (GlcN6P) and uridine diphosphate N-acetyl-glucosamine-6-phosphate (UDP-GlcN6P). Fructose-6-phosphate (Fru6P) is a common intermediary between glycolysis and the HBP. Changes in HBP regulation cause abnormal protein N-glycosylation and O-linked-N-acetylglucosamine modification (O-GlcNAcylation), affecting protein function and modifying cellular responses to signals. The HBP enzymes glucosamine-6-phosphate deaminases 1 and 2 (GNPDA1 and 2) turn GlcN6P back into Fru6P and ammonium, and have been implicated in cancer and metabolic diseases. Despite the plentiful literature on this topic, the mechanisms involved are just beginning to be studied. In this review, we summarize, for the first time, the current knowledge regarding the possible roles of the isoenzymes of both GNPDAs in the pathogenesis and development of metabolic diseases and cancer from a molecular point of view, highlighting their importance not only in supplying carbon from glycolysis, but also in ammonia metabolism.

Higher detectability of amyloid with phenol Congo red compared with alkaline Congo red

IntroductionAmyloidosis is a heterogeneous group of conditions associated with tissue deposition of insoluble abnormal proteins that damage vital organs. Early diagnosis, when the deposits are minimal, determines the prognosis and requires histological confirmation. The commonly adopted gold standard technique is alkaline Congo red (ACR) staining, though its sensitivity is limited. There is a need for a simple and inexpensive screening method offering a better chance of detecting mini­mal amyloid deposits. The aim of this study was to compare amyloid detectability with ACR and phenol Congo red (PHCR) staining techniques for early detection of minimal deposits.Material and methodsWe assessed 452 tissue specimens (including adipose tissue, gastrointestinal mucosa, labial salivary gland, myocardium, and bone marrow) from 425 patients with clinically suspected systemic or local amyloidosis, which had been sent to the Pathology Laboratory of the National Institute of Geriatrics, Rheumatology and Rehabilitation in Warsaw. Adjacent sections from each specimen were stained with ACR and PHCR. If amyloid was detected, immunohistochemical typing was conducted. The consistency of the two staining methods was expressed as Cohen’s κ coefficient.ResultsA total of 169 tissue specimens (37%) yielded positive readings, with 93 cases ACR(+) and PHCR(+); 75 cases ACR(–) and PHCR(+), and 1 case ACR(+) and PHCR(–). The percentage agreement between the staining methods was 83%, with the Cohen’s κ coefficient value of 0.60 (95% CI: 0.52–0.69), which corresponds to moderate agreement according to Fleiss. Additional immunohistochemical amyloid typing, conducted in ACR(–) and PHCR(+) specimens, yielded conclusive results in 82% of cases.ConclusionsThe use of PHCR staining as a screening method in suspected amyloidosis improves amyloid (light chain, transthyretin, and amyloid A protein) detectability in various tissues. The PHCR staining specificity should be verified via electron microscopy and/or mass spectrometry.

Pathophysiology of Normal Pressure Hydrocephalus

The current perspective for the pathophysiology of normal pressure hydrocephalus is focusing on stiffness of the central nervous tissue, especially on a type of cerebrovascular disorder. Rigid intracranial vessels and tissues derived by either vascular risk factors or aging may lead into impaired dynamics of the cerebrospinal fluid such as increased pulsatility and decreased absorption of the cerebrospinal fluid. Enlarged ventricle may result in a decrease of blood perfusion in brain parenchyma, and in turn global hypoxia and neuro-inflammation along with a breakdown of the blood-brain-barrier. Deterioration of the glymphatic pathway, the crucial disposal pathway of the waste product of the brain, also might contribute to the irreversible injury of the nervous tissue by deposition of abnormal toxic proteins including amyloid beta. Of note, the pathophysiology of the normal pressure hydrocephalus is moving to a type of cerebrovascular disorder instead of the etiology of idiopathic.

Delays in diagnosis and treatment initiation of ATTR cardiac amyloidosis: a real-world data analysis

Abstract Introduction Cardiac amyloidosis (CA) is a serious condition characterized by the accumulation of abnormal protein deposits in the heart muscle, leading to functional impairments and, ultimately, heart failure. Transthyretin amyloid cardiomyopathy (ATTR-CM) is the most common form encountered in CA diagnosis with previously underestimated prevalence. ATTR-CM poses a diagnostic challenge, with a substantial number of cases diagnosed late and at advanced stages. The availability of specific pharmacological treatment using the transthyretin-stabilizer tafamidis further emphasizes the need for timely diagnosis. Here, we aim to assess delays in diagnosis and initiation of therapy in a real-world collective of patients with ATTR-CM. Methods All individuals diagnosed from 01/2018 to 05/2023 with ATTR-CM at our university hospital, Germany, were systematically assessed for eligibility in this study. Specifically, we enrolled patients who were undergoing transthyretin stabilizer therapy. The investigation aimed to determine the duration, in days, from the initial suspicion of heart disease to the definitive diagnosis of ATTR-CM. It was also investigated whether the diagnosis of ATTR-CM was made more quickly over time as awareness increased. Additionally, the study assessed the time elapsed until patients received pharmacological therapy following the confirmed diagnosis. The study was approved by the local ethics committee (23-11500-BO). Results After screening of 194 consecutive patients, 154 were included in the analysis, while 40 patients were excluded due to insufficient records. The results of this study reveal that a median of 300 (113-962) days elapsed from the initial suspicion of amyloidosis to the final confirmation. Initial indications of CA often presented as nonspecific symptoms such as unclear dyspnea (16.2% n=25), abnormal echocardiography (75.3% n=116), or, in rare cases, incidental findings (8.4% n=13). Following the diagnosis, an additional median of 84 (46-163.5) days passed before the first prescription of a transthyretin stabilizer. To assess an improvement of ATTR-CM diagnosis over time, we stratified the data into tertiles by date of first diagnosis. The results showed a gradually decrease in medium time to diagnosis of 466 (181-1035) days in the earliest tertile (2018-2019) to 389 (141-1508) days in the most recent tertile (2022-2023) (p&amp;lt;0.001). Conclusion This study shows a major healthcare deficit and underscores the medical need for improved screening procedures and diagnostic modalities to expedite the timely diagnosis of CA, as early identification of the condition is crucial for enhancing the quality of life for patients and preventing life-threatening complications.

Novel Perspectives in the Management of Colorectal Cancer: Mechanistic Investigations Into the Reversal of Drug Resistance via Active Constituents Derived From Herbal Medicine.

The high incidence and mortality rate of colorectal cancer have become a significant global health burden. Chemotherapy has been the traditional treatment for colorectal cancer and has demonstrated promising antitumor effects, leading to significant improvements in patient survival. However, the development of chemoresistance poses a major challenge during chemotherapy in colorectal cancer, significantly impeding treatment efficacy and affecting patient prognosis. Despite the development of a variety of novel anticolorectal cancer chemotherapy agents, their effectiveness and side effects vary, possibly due to the complex mechanisms of resistance in colorectal cancer. Abnormal drug metabolism or protein targets are the most direct causes of resistance. Further studies have revealed that these resistance mechanisms involve biochemical processes such as altered protein expression, autophagy, and epithelial-mesenchymal transitions. Herbal active ingredients offer an alternative treatment option and have shown promise in reversing colorectal cancer drug resistance. This paper aims to summarize the role of various biochemical processes and key protein targets in the occurrence and maintenance of resistance mechanisms in colorectal cancer. Additionally, it elaborates on the mechanisms of action of herbal active ingredients in reversing colorectal cancer drug resistance. The article also discusses the limitations and opportunities in developing novel anticolorectal cancer drugs based on herbal medicine.

The Research Progress of Metformin Regulation of Metabolic Reprogramming in Malignant Tumors.

Metabolism reprogramming is a crucial hallmark of malignant tumors. Tumor cells demonstrateenhanced metabolic efficiency, converting nutrient inputs into glucose, amino acids, and lipids essential for theirmalignant proliferation and progression. Metformin, a commonly prescribed medication for type 2 diabetes mellitus,has garnered attention for its potential anticancer effects beyond its established hypoglycemic benefits. This review adopts a comprehensive approach to delineate the mechanisms underlying metabolite abnormalities within the primary metabolic processes of malignant tumors. This review examines the abnormal activation of G protein-coupled receptors (GPCRs) in these metabolic pathways, encompassing aerobic glycolysis with increased lactate production in glucose metabolism, heightened lipid synthesis and cholesterol accumulation in lipid metabolism, and glutamine activation alongside abnormal protein post-translational modifications in amino acid and protein metabolism. Furthermore, the intricate metabolic pathways and molecular mechanisms through which metformin exerts its anticancer effects are synthesized and analyzed, particularly its impacts on AMP-activated protein kinase activation and the mTOR pathway. The analysis reveals a multifaceted understanding of how metformin can modulate tumor metabolism, targeting key nodes in metabolic reprogramming essential for tumor growth and progression. The review compiles evidence that supports metformin's potential as an adjuvant therapy for malignant tumors, highlighting its capacity to interfere with critical metabolic pathways. In conclusion, this review offers a comprehensive overview of the plausible mechanisms mediating metformin's influence on tumor metabolism, fostering a deeper comprehension of its anticancer mechanisms. By expanding the clinical horizons of metformin and providing insight into metabolism-targeted tumor therapies, this review lays the groundwork for future research endeavors aimed at refining and advancing metabolic intervention strategies for cancer treatment.

Copper Overload Promotes β-amyloid Induced NLRP3/Caspase-1/GSDMD-Mediated Pyroptosis in Alzheimer's Disease.

Alzheimer's disease (AD) is characterized by cognitive decline and abnormal protein accumulation. Copper imbalance and pyroptosis play significant roles in the pathogenesis of AD. Recent studies have suggested that dysregulated copper homeostasis contributed to β-amyloid accumulation, which may activate the NOD-like receptor protein 3 (NLRP3)-related pyroptosis pathway, promoting neuronal damages and AD progression. Therefore, the present study aims to investigates whether copper facilitates AD through exacerbating β-amyloid (Aβ) induced activation of NLRP3/Caspase-1/Gasdermin D (GSDMD)-mediated neuronal cell pyroptosis. Mouse hippocampal HT-22 cells were cultured with Aβ1-42 oligomer for 24 h as AD Model group. CuCl2 treatment was administered to the AD cell model, and cell survivability levels were detected by Cell Counting Kit-8 (CCK-8), TdT-mediated dUTP nick end labeling (TUNEL), and other relevant kits. Mitochondrial function was evaluated using Mitochondrial membrane potential dye JC-1 and transmission electron microscopy (TEM). After intervention with the NLRP3 inhibitor MCC950, activation of the NLRP3/Caspase-1/GSDMD pathway by copper ions (Cu2+) was confirmed via Western Blot. Thioredoxin T (ThT) fluorescence assay was performed to observe the aggregation effect of Aβ induced by Cu2+ overload. CuCl2 treatment of the AD cell model resulted in up-regulation of the levels of Lactate Dehydrogenase (LDH), Interleukin-1β (IL-1β), and IL-18 expression, which indicated activation of pyroptosis. We observed a significant decrease in mitochondrial membrane potential, mitochondrial swelling, and loss of mitochondrial cristae by fluorescence microscopy and TEM. ThT fluorescence imaging showed that Cu2+ promoted Aβ aggregation and up-regulated NLRP3, apoptosis-associated speck-like protein containing a CARD (ACS), Caspase-1, Cleaved Caspase-1, GSDMD, and Gasdermin D N-terminal (GSDMD-NT). The NLRP3 inhibitor MCC950 partially reversed Cu2+-mediated pyroptosis in HT-22 cells. Exposure to copper ions disrupt mitochondrial copper homeostasis, promotes Aβ aggregation, and activates NLRP3 inflammasomes, further promoting the Aβ aggregation activated pyroptosis in AD cell models.

Immunotherapy in Alzheimer's Disease: Current Status and Future Directions.

Alzheimer's disease (AD) is a progressive neurological disorder characterized by memory loss, cognitive decline, and behavioral changes. Immunotherapy aims to harness the immune system to target the underlying pathology of AD and has shown promise as a disease-modifying treatment for AD. By focusing on the underlying disease pathogenesis and encouraging the removal of abnormal protein aggregates in the brain, immunotherapy shows promise as a potential treatment for AD. The development of immunotherapy for AD began with early attempts to use antibodies to target beta-amyloid. The amyloid hypothesis which suggests that the accumulation of beta-amyloid in the brain triggers the pathological cascade that leads to AD has been a driving force behind the development of immunotherapy for AD. However, recent clinical trials of monoclonal antibodies targeting amyloid-β have shown mixed results, highlighting the need for further research into alternative immunotherapy approaches. Additionally, the safety and efficacy of immunotherapy for AD remain an area of active investigation. Some immunotherapeutic approaches have shown promise, while others have been associated with significant side effects, including inflammation of the brain. Sleep has a significant impact on various physiological processes, including the immune system, and has been linked to the pathogenesis of AD. Thus, improving sleep quality and duration may benefit the immune system and potentially enhance the effectiveness of immunotherapeutic approaches for AD. In this review, we discussed the promises of immunotherapy as a disease-modifying treatment for AD as well as possible methods to improve the efficacy and safety of immunotherapy to achieve better therapeutic outcomes.

A Randomized-Controlled Trial Targeting Cognition in Early Alzheimer's Disease by Improving Sleep with Trazodone (REST).

Alzheimer's disease (AD) is a leading cause of mortality and morbidity among aging populations worldwide. Despite arduous research efforts, treatment options for this devastating neurodegenerative disease are limited. Sleep disturbances, through their link to changes in neural excitability and impaired clearance of interstitial abnormal protein aggregates, are a key risk factor for the development of AD. Research also suggests that the neuroprotective effects of sleep are particularly active during slow wave sleep. Given the strong link between sleep disturbance and AD, targeting sleep in the prodromal stages of AD, such as in mild cognitive impairment (MCI), represents a promising avenue for slowing the onset of AD-related cognitive decline. In efforts to improve sleep in older individuals, several pharmacologic approaches have been employed, but many pose safety risks, concern for worsening cognitive function, and fail to effectively target slow wave sleep. Trazodone, a safe and widely used drug in the older adult population, has shown promise in inducing slow wave sleep in older adults, but requires more rigorous research to understand its effects on sleep and cognition in the prodromal stages of AD. In this review, we present the rationale and study design for our randomized, double-bind, placebo-controlled, crossover trial (NCT05282550) investigating the effects of trazodone on sleep and cognition in 100 older adults with amnestic MCI and sleep complaints.

The neurotrophic factor MANF regulates autophagy and lysosome function to promote proteostasis in Caenorhabditis elegans

The conserved mesencephalic astrocyte-derived neurotrophic factor (MANF) is known for protecting dopaminergic neurons and functioning in various other tissues. Previously, we showed that Caenorhabditis elegans manf-1 null mutants exhibit defects such as increased endoplasmic reticulum (ER) stress, dopaminergic neurodegeneration, and abnormal protein aggregation. These findings suggest an essential role for MANF in cellular processes. However, the mechanisms by which intracellular and extracellular MANF regulate broader cellular functions remain unclear. We report a unique mechanism of action for MANF-1 that involves the transcription factor HLH-30/TFEB-mediated signaling to regulate autophagy and lysosomal function. Multiple transgenic strains overexpressing MANF-1 showed extended lifespan of animals, reduced protein aggregation, and improved neuronal survival. Using fluorescently tagged MANF-1, we observed tissue-specific localization of the protein, which was dependent on the ER retention signal. Further subcellular analysis showed that MANF-1 localizes within cells to the lysosomes and utilizes the endosomal pathway. Consistent with the lysosomal localization, our transcriptomic study of MANF-1 and analyses of autophagy regulators demonstrated that MANF-1 promotes proteostasis by regulating autophagic flux and lysosomal activity. Collectively, our findings establish MANF as a critical regulator of stress response, proteostasis, and aging.

Value of Functional Protein S Activity Assays for Detection of Type II Protein S Deficiency

Abstract Background Protein S deficiency is a hereditary thrombophilia which occurs in three forms: Type I (quantitative), type II (qualitative) and type III (qualitative due to a gain of function). Literature suggests that of these, type II is the rarest and most difficult to diagnose. Type II protein S deficiency is only detectable by assaying protein S activity with a functional, clot-based test. However, this test is susceptible to interference and has a lower specificity when compared to antigen assays used to detect free and total protein S levels. Subsequently, the Choosing Wisely Guidelines released by the ABIM Foundation recommends against using protein S activity assays entirely. Instead, they suggest using only free protein S antigen assays. Although the rationale is to avoid false positive results from the protein S activity assay, it ultimately may result in a failure to detect type II protein S deficiency. Objective This study, performed at a tertiary medical center in the Midwestern region of the United States, aims to determine the proportion of false positives in functional assays as well as the percent of true type II protein S deficiency cases within this testing population. Methods All cases with abnormal protein S function within the institution were evaluated from July 2018 through July 2023 and classified as acquired or hereditary deficiencies. Cases were classified as acquired if there was evidence of liver disease, vitamin K deficiency, ongoing thrombosis, consumption, disseminated intravascular coagulopathy, or pregnancy. Possible hereditary deficiency cases were classified as type I, type II and type III: Type I if all assays were low, type III if both active and free protein S assays were low with normal total protein S, and type II if only protein S activity was low. The cutoff defined for normal total and free protein S levels was greater than 70% activity, and the low protein S activity cutoff was defined as less than 50%. Patients with low protein S activity but normal immunologic protein S and an elevated factor VIII were considered falsely low values. Chart review will be performed for remaining cases with low protein S activity to rule out confounders such as vitamin K deficiency, warfarin use, acute phase reaction, or pregnancy. Results From a total of 8805 panels performed to assess for possible thrombophilia, 1580 (18%) were found to have decreased protein S activity. Of these cases, 599 (38%) were considered falsely decreased due to elevated factor VIII levels. 322 cases (3.7%) were considered possible hereditary deficiencies: 217 type III (2.5%), 27 type II (0.3%), and 80 type I (0.9%). Discussion Our data indicates the prevalence of subtypes may be differently distributed than previously believed, which may call for current guidelines to be reevaluated.

Association of regular plasmapheresis donation with serum protein and electrolyte levels: a multicentre cross-sectional study in China

BackgroundChina’s plasmapheresis donation policy differs from that of Western countries. The association between regular plasmapheresis donation and donor health in China is still unknown.ObjectivesTo investigate the association of regular plasmapheresis...

Tumefactive Pulmonary amyloidosis in an elderly male: A Diagnostic Dilemma

Abstract Introduction/Objective Tumefactive pulmonary amyloidosis is a rare variant of pulmonary amyloidosis characterized by the extracellular deposition of abnormal protein fibrils in the lung parenchyma, forming tumor-like masses called amyloidomas. Although most cases are clinically silent, it may present with findings that mimic a wide range of respiratory conditions (eg. primary or metastatic malignant nodules, granulomatous disease, multiple pulmonary hamartomas etc), thereby necessitating a comprehensive and broad-based approach to differential diagnosis. Methods/Case Report We present a case of an 88-year-old male with a history of smoking and multiple comorbidities. He presented with numerous bilateral pulmonary nodules identified on a CT scan, concerning for malignancy. A biopsy from a left upper lobe lesion revealed necrotic tissue and was non-diagnostic. A PET scan to assess for metastatic disease was unremarkable, and demonstrated mild hypermetabolic activity, confined to the lungs, with standardized uptake values (SUV) ranging from 4.3 to a maximum SUV of 8.9. A subsequent right lung biopsy was positive for amyloid, confirmed by Congo red staining. A Mass spectrometry analysis further identified the amyloid as AL type. Serum, and urine protein electrophoresis with immunofixation were negative for M protein and the serum free light chain assay was normal as well. Significantly, the bone marrow biopsy also yielded normal results, and the patient was diagnosed with a localized form of AL amyloidosis. Results (if a Case Study enter NA) NA Conclusion This case highlights how tumefactive pulmonary amyloidosis poses a diagnostic challenge due to its rarity and resemblance to malignancy on imaging. Careful histopathological examination, including immunohistochemical stains and amyloid typing, was pivotal in establishing the correct diagnosis and underscores the essential role of pathology and laboratory medicine in differentiating rare pulmonary conditions, along with the need for a multidisciplinary approach in complex diagnostic scenarios.

Mind the Gap: Influence of Monoclonal Immunoglobulin on Anion Gap in Multiple Myeloma

Abstract Background Multiple myeloma (MM) is a plasma cell disorder in which anion gap and sodium measurement are critically influenced by the presence of abnormal protein concentrations. This study investigates the relationship between anion gap, pseudohyponatremia, and monoclonal immunoglobulin levels (IgG, IgA, IgM), particularly the common IgG. Focusing on the clinical implications of these laboratory results. Methods We retrospectively analyzed data from 136 patients diagnosed with MM, focusing on anion gap values, monoclonal immunoglobulin levels, and sodium levels. The patients were categorized based on their anion gap values (&amp;lt;8) into five groups (anion gap=3, 4, 5, 6, and 7). Monoclonal immunoglobulin levels were standardized to the same units as the anion gap for direct comparison. Additionally, we investigated the pseudohyponatremia by examining sodium levels in these patients. Results Among the 136 MM patients, 70 patients’ anion gap were lower than 8. A negative correlation between MM monoclonal immunoglobulins and anion gap values were observed. The anion gap decreased from 7 to 3 as the IgG average levels ranged increasing from 1755 mg/dL to 2655 mg/dL (RI 610-1616 mg/dL). Similarly, the anion gap decreased from 6 to 3 as the IgM average levels ranged increasing from 1170 mg/dL to 2880 mg/dL (RI 35-242 mg/dL). Additionally, a number of low sodium levels (&amp;lt;136 mmol/L) was observed in each group. Conclusion Our study highlights the negative impact of MM monoclonal immunoglobulins, particularly IgG and IgM, on the anion gap. Both laboratory and clinical personnel should be aware of these phenomena, might prevent unnecessary diagnosis, streamlining patient management and avoiding potential mismanagement.

Exploring the interplay between zinc‐induced protein dyshomeostasis and mitochondrial dysfunction using viscosity‐sensitive sensor

AbstractMitochondria are crucial sites for protein quality control within cells. When mitochondrial stress is triggered by protein misfolding, it can accelerate abnormal protein aggregation, potentially inducing various diseases. This study developed a cascade‐responsive sensor, named AggHX, to monitor the microenvironment of protein aggregation induced by zinc (II) ions and the accompanying mitochondrial dysfunction. The AggHX consists of two key components: (1) A Zn2+ recognition group for triggering a fluorescent enhance response, and (2) a near‐infrared BODIPY scaffold that detects viscosity changes in cell aggregation via HaloTag. This sensor's mechanism of action is elucidated through photochemical and biochemical characterizations. To further investigate the relationship between protein aggregation and mitochondrial homeostasis, we employ fluorescence lifetime imaging microscopy to assess viscosity changes in protein aggregates under intracellular Zn2+ stress. This research provides insights into the dynamic behavior and spatial distribution of protein aggregates and mitochondria, contributing to a deeper understanding of their physiological roles in cellular processes and potential implications in disease pathology.

Deciphering Pathways and Thermodynamics of Protein Assembly Using Native Mass Spectrometry.

Protein oligomerization regulates many critical physiological processes, and its dysregulation can contribute to dysfunction and diseases. Elucidating the assembly pathways and quantifying their underlying thermodynamic and kinetic parameters are crucial for a comprehensive understanding of biological processes and for advancing therapeutics targeting abnormal protein oligomerization. Established binding assays, with limited mass precision, often rely on simplified models for data interpretation. In contrast, high-resolution native mass spectrometry (nMS) can directly determine the stoichiometry of biomolecular complexes in vitro. However, quantification is hindered by the fact that the relative abundances of gas-phase ions generally do not reflect solution concentrations due to nonuniform response factors. Recently, slow mixing mode (SLOMO)-nMS, which can quantify the relative response factors of interacting species, has been demonstrated to reliably measure the affinity (Kd) of binary biomolecular complexes. Here, we introduce an extended form of SLOMO-nMS that enables simultaneous quantification of the thermodynamics in multistep association reactions. Application of this method to homo-oligomerization of concanavalin A and insulin confirmed the reliability of the assay and uncovered details about the assembly processes that had previously resisted elucidation. Results acquired using SLOMO-nMS implemented with charge detection shed new light on the binding of recombinant human angiotensin-converting enzyme 2 and the SARS-CoV-2 spike protein. Importantly, new assembly pathways were uncovered, and the affinities of these interactions, which regulate host cell infection, were quantified. Together, these findings highlight the tremendous potential of SLOMO-nMS to accelerate the characterization of protein assembly pathways and thermodynamics and, in so doing, enhance fundamental biological understanding and facilitate therapeutic development. https://orcid.org/0000-0002-3389-7112.

Etiology, Clinical Profiles, and Outcomes of Acute Encephalitis Syndrome Cases Admitted to a Tertiary Care Center in Myanmar in 2023.

The diagnosis of encephalitis is a challenging problem due to the heterogeneity of clinical presentations. The objective was to determine the etiology, clinical features, laboratory parameters, radiological findings, and in-hospital outcome of acute encephalitis syndrome (AES) cases in Myanmar. A prospective descriptive study was conducted at the Neuromedical Ward of Yangon General Hospital from March to August 2023. Eighty-one AES cases were enrolled, and cerebrospinal fluid (CSF) samples were collected. A Qiastat ME Panel was used to detect viral, bacterial, and fungal pathogens. Seventeen out of eighty-one (21%) cases were non-encephalitis with alternative definite diagnosis. Among the remaining 64 encephalitis cases, the exact infectious and immune etiologies were identified in 31 of 64 cases (48.4%); 26 of these (83.9%) were due to infectious causes and 5 (16.1%) were immune encephalitis. Among the infectious causes, six Herpes Simplex Virus-1-, one bacteriologically confirmed and seven probable Mycobacterium tuberculosis-, three Haemophilus influenzae-, two Streptococcus pneumoniae-, one Streptococcus pyogenes-, one Varicella-Zoster Virus (Ramsay Hunt Syndrome with meningoencephalitis)-, and two Cryptococcus neoformans-infected patients and rare causes such as Listeria monocytogenes, Burkholdelria cepacia, Sphingomonas paucimobilis, and Aspergillus were identified. One case was a dual infection with Haemophilus influenzae and Cryptococcus neformans. Abnormal protein levels and CSF pleocytosis were significantly higher among bacterial causes (p < 0.05). In total, 6.45% (2/31) of encephalitis patients with identified causes and 12.12% (4/33) of those without an identified organism had poor outcome. Herpes encephalitis and tuberculous meningoencepalitis were the commonest. This study highlighted that molecular testing with a multidisciplinary approach is required to ensure the right treatment on time.

Functional Relationships between L1CAM, LC3, ATG12, and Aβ.

Abnormal protein accumulations in the brain are linked to aging and the pathogenesis of dementia of various types, including Alzheimer's disease. These accumulations can be reduced by cell indigenous mechanisms. Among these is autophagy, whereby proteins are transferred to lysosomes for degradation. Autophagic dysfunction hampers the elimination of pathogenic protein aggregations that contribute to cell death. We had observed that the adhesion molecule L1 interacts with microtubule-associated protein 1 light-chain 3 (LC3), which is needed for autophagy substrate selection. L1 increases cell survival in an LC3-dependent manner via its extracellular LC3 interacting region (LIR). L1 also interacts with Aβ and reduces the Aβ plaque load in an AD model mouse. Based on these results, we investigated whether L1 could contribute to autophagy of aggregated Aβ and its clearance. We here show that L1 interacts with autophagy-related protein 12 (ATG12) via its LIR domain, whereas interaction with ubiquitin-binding protein p62/SQSTM1 does not depend on LIR. Aβ, bound to L1, is carried to the autophagosome leading to Aβ elimination. Showing that the mitophagy-related L1-70 fragment is ubiquitinated, we expect that the p62/SQSTM1 pathway also contributes to Aβ elimination. We propose that enhancing L1 functions may contribute to therapy in humans.