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1.
Curr Alzheimer Res ; 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39161146

ABSTRACT

BACKGROUND: Neurodegenerative disorders like Alzheimer's disease (AD) involve the abnormal aggregation of tau protein, which forms toxic oligomers and amyloid deposits. The structure of tau protein is influenced by the conformational states of distinct proline residues, which are regulated by peptidyl-prolyl isomerases (PPIases). However, there has been no research on the impact of human cyclophilin A (CypA) as a PPIase on (non-phosphorylated) tau protein aggregation. METHODS: On the basis of these explanations, we used various spectroscopic techniques to explore the effects of CypA on tau protein aggregation behavior. RESULTS: We demonstrated the role of the isomerization activity of CypA in promoting the formation of tau protein amyloid fibrils with well-defined and highly ordered cross-ß structures. According to the "cistauosis hypothesis," CypA's ability to enhance tau protein fibril formation in AD is attributed to the isomerization of specific proline residues from the trans to cis configuration. To corroborate this theory, we conducted refolding experiments using lysozyme as a model protein. The presence of CypA increased lysozyme aggregation and impeded its refolding process. It is known that proper refolding of lysozyme relies on the correct (trans) isomerization of two critical proline residues. CONCLUSION: Thus, our findings confirmed that CypA induces the trans-to-cis isomerization of specific proline residues, ultimately leading to increased aggregation. Overall, this study highlights the emerging role of isomerization in tau protein pathogenesis in AD.

2.
Protein Expr Purif ; 223: 106555, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39004261

ABSTRACT

Whey, a valuable byproduct of dairy processing, contains essential proteins like ß-lactoglobulin (ßLG) and α-lactalbumin (αLA), making it a focus of research for its nutritional benefits. Various techniques, including chromatography and membrane filtration, are employed for protein extraction, often requiring multiple purification steps. One approach that has gained prominence for the purification and concentration of proteins, including those present in whey, is the use of polyethylene glycol (PEG) in aqueous two-phase systems. Our study simplifies this process by using PEG alone for whey protein purification. This approach yielded impressive results, achieving 92 % purity for ßLG and 90 % for αLA. These findings underscore the effectiveness of PEG-based purification in isolating whey proteins with high purity.


Subject(s)
Lactalbumin , Lactoglobulins , Milk , Polyethylene Glycols , Animals , Lactalbumin/isolation & purification , Lactalbumin/chemistry , Lactoglobulins/isolation & purification , Lactoglobulins/chemistry , Milk/chemistry , Cattle , Polyethylene Glycols/chemistry , Whey Proteins/chemistry , Whey Proteins/isolation & purification
3.
J Nutr Biochem ; 132: 109693, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38880191

ABSTRACT

The Ketogenic Diet (KD) is a dietary regimen that is low in carbohydrates, high in fats, and contains adequate protein. It is designed to mimic the metabolic state of fasting. This diet triggers the production of ketone bodies through a process known as ketosis. The primary objective of KD is to induce and sustain ketosis, which has been associated with numerous health benefits. Recent research has uncovered promising therapeutic potential for KD in the treatment of various diseases. This includes evidence of its effectiveness as a dietary strategy for managing intractable epilepsy, a form of epilepsy that is resistant to medication. We are currently assessing the efficacy and safety of KD through laboratory and clinical studies. This review focuses on the anti-inflammatory properties of the KD and its potential benefits for neurological disorders and the gut-brain axis. We also explore the existing literature on the potential effects of KD on cardiac health. Our aim is to provide a comprehensive overview of the current knowledge in these areas. Given the encouraging preliminary evidence of its therapeutic effects and the growing understanding of its mechanisms of action, randomized controlled trials are warranted to further explore the rationale behind the clinical use of KD. These trials will ultimately enhance our understanding of how KD functions and its potential benefits for various health conditions. We hope that our research will contribute to the body of knowledge in this field and provide valuable insights for future studies.


Subject(s)
Brain-Gut Axis , Cardiovascular Diseases , Diet, Ketogenic , Nervous System Diseases , Humans , Cardiovascular Diseases/diet therapy , Nervous System Diseases/diet therapy , Nervous System Diseases/metabolism , Animals , Gastrointestinal Microbiome/physiology , Ketone Bodies/metabolism
4.
Int Immunopharmacol ; 138: 112561, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38941673

ABSTRACT

Psoriasis, a chronic autoimmune skin disorder, causes rapid and excessive skin cell growth due to immune system dysfunction. Numerous studies have shown that flavonoids have anti-psoriatic effects by modulating various molecular mechanisms involved in inflammation, cytokine production, keratinocyte proliferation, and more. This study reviewed experimental data reported in scientific literature and used network analysis to identify the potential biological roles of flavonoids' targets in treating psoriasis. 947 records from Web of Sciences, ScienceDirect database, Scopus, PubMed, and Cochrane library were reviewed without limitations until June 26, 2023. 66 articles were included in the systematic review. The ten genes with the highest scores, including interleukin (IL)-10, IL-12A, IL-1ß, IL-6, Tumor necrosis factor-α (TNF-α), Janus kinase 2 (JAK 2), Jun N-terminal kinase (JUN), Proto-oncogene tyrosine-protein kinase Src (SRC), Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), and Signal transducer and activator of transcription 3 (STAT3), were identified as the hub genes. KEGG pathway analysis identified connections related to inflammation and autoimmune responses, which are key characteristics of psoriasis. IL-6, STAT3, and JUN's presence in both hub and enrichment genes suggests their important role in flavonoid's effect on psoriasis. This comprehensive study highlights how flavonoids can target biological processes in psoriasis, especially when combined for enhanced effectiveness.


Subject(s)
Flavonoids , Keratinocytes , Proto-Oncogene Mas , Psoriasis , Humans , Psoriasis/drug therapy , Psoriasis/immunology , Keratinocytes/drug effects , Keratinocytes/metabolism , Flavonoids/pharmacology , Flavonoids/therapeutic use , Animals , Cytokines/metabolism , Drug Synergism , Signal Transduction/drug effects
5.
J Biomol Struct Dyn ; : 1-15, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38334282

ABSTRACT

The first class of carbonic anhydrase inhibitors (CAIs) discovered was sulfonamides, but their clinical use is limited due to side effects caused by their inhibition of multiple CA isoforms. To overcome this, researchers have focused on developing isoform-selective CAIs. This study involved the synthesis and characterization of novel carboxylic acid/sulfonamide derivatives. We investigated the interaction between these compounds and the human carbonic anhydrase II (hCA II) isoform using spectroscopic and computational methods. The synthesized compounds were evaluated based on their IC50, Kd and Ki values, and it was found that the inhibitory potency and binding affinity of the compounds increased with the number of carboxylic acids zinc binding groups. Specifically, the compound C4, with three carboxylic acid groups, showed the strongest inhibitory potency. Fluorescence measurements revealed that all compounds quenched the intrinsic fluorescence of hCA II through a dynamic quenching process, and each compound had one binding site in the hCA II structure. Thermodynamic analysis indicated hydrogen bonds and van der Waals interactions played key roles in the binding of these compounds to hCA II. Docking studies showed that the carboxylic acid groups directly attached to the zinc ion in the active site, displacing water/hydroxide ions and causing steric hindrance. Overall, the strengthening of inhibitory activity and the binding power of these carboxylic acid derivatives for the hCA II makes these compounds interesting for designing novel hCA II inhibitors.Communicated by Ramaswamy H. Sarma.

6.
Int J Cancer ; 154(7): 1131-1142, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37860922

ABSTRACT

As healthcare systems are improving and thereby the life expectancy of human populations is increasing, cancer is representing itself as the second leading cause of death. Although cancer biologists have put enormous effort on cancer research so far, we still have a long way to go before being able to treat cancers efficiently. One interesting approach in cancer biology is to learn from natural resistance and/or predisposition to cancer. Cancer-resistant species and tissues are thought-provoking models whose study shed light on the inherent cancer resistance mechanisms that arose during the course of evolution. On the other hand, there are some syndromes and factors that increase the risk of cancer development, and revealing their underlying mechanisms will increase our knowledge about the process of cancer formation. Here, we review natural resistance and predisposition to cancer and the known mechanisms at play. Further insights from these natural phenomena will help design future cancer research and could ultimately lead to the development of novel cancer therapeutic strategies.


Subject(s)
Neoplasms , Humans , Neoplasms/drug therapy , Disease Susceptibility , Genotype , Immunity, Innate
7.
J Biomol Struct Dyn ; : 1-15, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37878050

ABSTRACT

The aggregation of tau protein in the form of paired helical filament (PHF) leads to the breakdown of microtubule structure and the development of neurodegenerative disorders, such as Alzheimer's disease. Therefore, inhibiting tau protein aggregation is a potential strategy for preventing the progression of these disorders. In this study, sulfamethoxazole (SMZ), an antibiotic that easily crosses the blood-brain barrier and interacts with tau protein, was tested for its ability to inhibit tau aggregation in vitro. Various multi-spectroscopic techniques including XRD, LDH cytotoxicity colorimetric assay, and microscopic imaging were employed. The results showed that SMZ effectively interacts with tau protein through hydrogen and van der Waals interactions. It also effectively inhibited tau protein aggregation in vitro and significantly reduced toxicity in the SH-SY5Y neuroblastoma cell line. Molecular docking and MD simulation results suggested that SMZ may reduce tau protein aggregation by interacting with the PHF6 motif. Overall, these findings indicate that SMZ has therapeutic potential as a tau protein aggregation inhibitor, at least under in vitro conditions. These findings suggest that SMZ has potential as a treatment for neurodegenerative disorders involving tau protein aggregation. However, further research is needed to confirm these results and assess the effectiveness of SMZ in animal models and clinical trials.Communicated by Ramaswamy H. Sarma.

8.
J Neuroimmune Pharmacol ; 18(3): 294-309, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37552452

ABSTRACT

Chronic insomnia is an inflammatory-related disease with an important pathological basis for various diseases which is a serious threat to a person's physical and mental health. So far, many hypotheses have been proposed to explain the pathogenesis of insomnia, among which inflammatory mechanisms have become the focus of scientific attention. In this regard, the aim of the present scooping review is to evaluate the potential benefits of natural compounds in treatment of chronic insomnia targeting nucleotide-binding oligomerization domain (NOD)-like receptor-pyrin-containing protein 3 (NLRP3)/caspase-1/IL-1ß axis as one of the most important activators of inflammatory cascades. The data show that compounds that have the potential to cause inflammation induce sleep disorders, and that inflammatory mediators are key molecules in regulating the sleep-related activity of neurons. In the inflammatory process of insomnia, the role of NLRP3 in the pathogenesis of insomnia has been gradually considered by researchers. NLRP3 is an intracellular sensor that recognizes the widest range of pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). After identification and binding to damage factors, NLRP3 inflammasome is assembled to activate the caspase-1 and IL-1ß. Increased production and secretion of IL-1ß may be involved in central nervous system dysregulation of physiological sleep. The current scooping review reports the potential benefits of natural compounds that target NLRP3 inflammasome pathway activity and highlights the hypothesis which NLRP3 /caspase-1/IL-1ß may serve as a potential therapeutic target for managing inflammation and improving symptoms in chronic insomnia.

9.
Curr Protein Pept Sci ; 24(6): 518-532, 2023.
Article in English | MEDLINE | ID: mdl-37259218

ABSTRACT

BACKGROUND: A hallmark pathology of Alzheimer's disease (AD) is the construction of neurofibrillary tangles, which are made of hyperphosphorylated Tau. The cis-proline isomer of the pThr/Ser-Pro sequence has been suggested to act as an aggregation precursor according to the 'Cistauosis' hypothesis; however, this aggregation scheme is not yet completely approved. Various peptidyl-prolyl isomerases (PPIases) may specifically isomerize cis/trans-proline bonds and restitute Tau's ability to attach microtubules and may control Tau amyloid aggregation in AD. METHODS: In this study, we provided experimental evidence for indicating the effects of the plant Cyclophilin (P-Cyp) from Platanus orientalis pollens on the Tau aggregation by various spectroscopic techniques. RESULTS: Our findings disclosed that the rate/extent of amyloid formation in the Tau sample which is incubated with P-Cyp decreased and these observations do not seem to be due to the macromolecular crowding effect. Also, as proven that 80% of the prolines in the unfolded protein are in the trans conformation, urea-induced unfolding analyses confirmed this conclusion and showed that the aggregation rate/extent of urea-treated Tau samples decreased compared with those of the native protein. Also, XRD analysis indicated the reduction of scattering intensities and beta structures of amyloid fibrils in the presence of P-Cyp. Therefore, the ability of P-Cyp to suppress Tau aggregation probably depends on cis to trans isomerization of proline peptide bonds (X-Pro) and decreasing cis isomers in vitro. CONCLUSION: The findings of the current study may inspire possible protective/detrimental effects of various types of cyclophilins on AD onset/progression through direct regulation of intracellular Tau molecules and provides evidence that a protein from a plant source is able to enter the cell cytoplasm and may affect the behavior of cytoplasmic proteins.


Subject(s)
Alzheimer Disease , Cyclophilins , Cyclophilins/metabolism , Amyloid/metabolism , Allergens , tau Proteins/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Pollen/metabolism , Proline/pharmacology , Proline/chemistry , Proline/metabolism , Urea , Amyloid beta-Peptides
10.
Biophys Chem ; 296: 106982, 2023 05.
Article in English | MEDLINE | ID: mdl-36868163

ABSTRACT

The formation of amyloid fibrils due to its association with fatal diseases, including Alzheimer's, has been investigated by many researchers. These common diseases, mostly become verified when it is too late to be treated. Currently, no cure is available for neurodegenerative diseases, and the process of diagnosing amyloid fibrils in the early stages, while there are fewer amyloid fibrils, has become an issue of interest. To do so, determining new probes with the highest binding affinity to the lowest number of amyloid fibrils is necessary. In this study, we proposed to employ new synthesized benzylidene-indandione derivatives as amyloid fibrils fluorescent detection probes. Native soluble proteins of insulin, bovine serum albumin (BSA), BSA amorphous aggregation, and insulin amyloid fibrils were used to evaluate our compounds' specificity to the amyloid structure. While ten synthesized compounds were examined individually, four of them including 3d, 3g, 3i, and 3j showed a high binding affinity with selectivity and specificity to amyloid fibrils, and their binding properties were also confirmed with in silico analysis. The drug-likeness prediction results for selected compounds by Swiss ADME server shows a satisfactory percentage of blood-brain barrier (BBB) permeability and gastrointestinal (GI) absorption for the compounds 3g, 3i, and 3j. More evaluation is needed to determine all properties of compounds in vitro and in vivo.


Subject(s)
Alzheimer Disease , Insulins , Humans , Amyloid beta-Peptides/chemistry , Alzheimer Disease/metabolism , Amyloid/metabolism , Benzylidene Compounds , Serum Albumin, Bovine/chemistry
11.
J Biomol Struct Dyn ; 41(22): 12686-12702, 2023.
Article in English | MEDLINE | ID: mdl-36755431

ABSTRACT

Diabetes is one of the most common metabolic diseases in humans and the use of herbal medicines is of great clinical importance to inhibit carbohydrate-hydrolyzing enzymes and reduce blood glucose levels in diabetic patients. Inhibition of glycosidase activity is an effective way to treat and prevent diabetes. Therefore, in this study, curcumin-based benzaldehyde derivatives were synthesized and used as influential agents in the treatment of diabetes with inhibitory properties against two carbohydrate-hydrolyzing enzymes α-glucosidase (α-Glu) and α-amylase (α-Amy) as significant therapeutic targets for reducing postprandial hyperglycemia. Overall, the findings showed that due to the specific inhibitory activity against α-Glu in comparison with α-Amy, as well as more stability and antioxidant activity than curcumin, C5 and C8 derivatives are potentially important anti-diabetic drugs, not only to decrease glycemic index but also to limit the activity of the main production pathways of reactive oxygen species (ROS) in diabetic patients.Communicated by Ramaswamy H. Sarma.


Subject(s)
Curcumin , Diabetes Mellitus , Humans , Curcumin/pharmacology , Hypoglycemic Agents/pharmacology , Glycoside Hydrolase Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/therapeutic use , Glycoside Hydrolases , alpha-Glucosidases/metabolism , alpha-Amylases , Diabetes Mellitus/drug therapy , Carbohydrates
12.
J Fluoresc ; 33(4): 1317-1324, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36640210

ABSTRACT

Amyloid formation due to protein aggregation is associated with several amyloid diseases (amyloidosis). The use of small organic ligands as inhibitors of protein aggregation is an attractive strategy for the treatment of these diseases. In the present study, we evaluated the in vitro inhibitory and destabilizing effects of Mesalazine on human insulin fibrillation. To induce fibrillation, human insulin was incubated in 50 mM glycine buffer (pH 2.0) at 50 °C. The effect of Mesalazine on insulin amyloid aggregation was studied using spectroscopic, imaging, and computational approaches. Based on the results, the Mesalazine in a concentration-dependent manner (different ratios (1:0.1, 1:0.5, 1:1, and 1:5) of the insulin to Mesalazine) prevented the formation of amyloid fibrils and destabilized pre-formed fibrils. In addition, our molecular docking study confirmed the binding of Mesalazine to insulin through hydrogen bonds and hydrophobic interactions. Our findings suggest that Mesalazine may have therapeutic potential in the prevention of insulin amyloidosis and localized amyloidosis.


Subject(s)
Amyloid , Amyloidosis , Humans , Amyloid/chemistry , Amyloid/metabolism , Mesalamine/pharmacology , Protein Aggregates , Molecular Docking Simulation , Amyloidogenic Proteins , Insulin/metabolism , Amyloidosis/drug therapy
13.
J Biomol Struct Dyn ; 41(16): 7975-7985, 2023.
Article in English | MEDLINE | ID: mdl-36166619

ABSTRACT

Carbonic anhydrase (CA) is a zinc metalloenzyme that facilitates the rapid conversion of water and carbon dioxide into proton and bicarbonate ion. CA isozymes have been broadly studied in many pathological/physiological processes. In the current research, a series of 4-hydroxy-L-proline derivatives were designed and chemically synthetized, and interaction of these carboxylic acid-based compounds with hCA II were evaluated. Results indicated that different derivatives had different potencies on hCAII inhibitory activity and among them, compounds 3 b and 3c had the lowest IC50 and Kd values than 4-hydroxy-L-proline and other derivatives and therefore had the most affinity to the hCA II enzyme. As a result, compounds 3 b and 3c were chosen for additional testing in this research. The Kinetic data demonstrated that 3 b and 3c inhibit the hCA II esterase activity in a linear competitive way, with Ki values in the low micromolar range. Fluorescence tests showed that the hCA II surface hydrophobicity is diminished in the presence of compounds 3 b and 3c, as confirmed by the decrease in ANS binding to hCA II in their presence. Docking results revealed that 3 b and 3c had more binding energy than 4-hydroxy-L-proline. Furthermore, these compounds could occupy the active site of hCA II, where they would interact with critical amino acid residues via non-covalent forces to inhibit hCA II. Overall, the strengthening of inhibitory activity and the binding power of these carboxylic acid derivatives (3 b and 3c) for the hCA II makes these compounds interesting for designing novel hCA II inhibitors.Communicated by Ramaswamy H. Sarma.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121806, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36108405

ABSTRACT

Curcumin (bis-α,ß-unsaturated ß-diketone) plays an important role in the prevention of numerous diseases, including diabetes. Curcumin, as an enzyme inhibitor, has ideal structural properties including hydrophobic nature, flexible backbone, and several available hydrogen bond (H-bond) donors and acceptors. In this study, curcumin-fused aldohexose derivatives 3(a-c) were synthesized and used as influential agents in the treatment of diabetes with inhibitory properties against two carbohydrate-hydrolyzing enzymes α-glucosidase (α-Gls) and α-amylase (α-Amy) which are known to be significant therapeutic targets for the reduction of postprandial hyperglycemia. These compounds were isolated, purified, and then spectrally characterized via FT-IR, Mass, 1H, and 13C NMR, which strongly confirmed the targeted product's formation. Also, their inhibitory properties against α-Gls and α-Amy were evaluated spectroscopically. The Results indicated that all compounds strongly inhibited α-Amy and α-Gls by mixed and competitive mechanisms, respectively. The intrinsic fluorescence of α-Amy was quenched by the interaction with compounds 1 and 3b through a dynamic quenching mechanism, and the 1 and 3b/α-Amy complexes were spontaneously formed, mainly driven by the hydrophobic interaction and hydrogen bonding. Fourier transform infrared spectra (FT-IR) comprehensively verified that the binding of compounds 1 and 3b to α-Amy would change the conformation and microenvironment of α-Amy, thereby inhibiting the enzyme activity. Docking and molecular dynamics (MD) simulations showed that all compounds interacted with amino acid residues located in the active pocket site of the proteins. In vivo studies confirmed the plasma glucose diminution after the administration of compound 3b to Wistar rats. Accordingly, the results of the current work may prompt the scientific communities to investigate the possibility of compound 3b application in the clinic.


Subject(s)
Curcumin , Diabetes Mellitus , Rats , Animals , Hypoglycemic Agents/chemistry , Curcumin/pharmacology , Spectroscopy, Fourier Transform Infrared , Rats, Wistar , alpha-Glucosidases/metabolism , alpha-Amylases/metabolism , Molecular Docking Simulation , Glycoside Hydrolase Inhibitors/chemistry
15.
Front Nutr ; 9: 981984, 2022.
Article in English | MEDLINE | ID: mdl-36386916

ABSTRACT

The future GCC-connected environmental risk factors expedited the progression of nCDs. Indeed, the emergence of AFs is becoming a global food security concern. AFs are lethal carcinogenic mycotoxins, causing damage to the liver, kidney, and gastrointestinal organs. Long-term exposure to AFs leads to liver cancer. Almost a variety of food commodities, crops, spices, herbaceous materials, nuts, and processed foods can be contaminated with AFs. In this regard, the primary sections of this review aim to cover influencing factors in the occurrence of AFs, the role of AFs in progression of nCDs, links between GCC/nCDs and exposure to AFs, frequency of AFs-based academic investigations, and world distribution of AFs. Next, the current trends in the application of PPs to alleviate AFs toxicity are discussed. Nearly, more than 20,000 published records indexed in scientific databases have been screened to find recent trends on AFs and application of PPs in AFs therapy. Accordingly, shifts in world climate, improper infrastructures for production/storage of food commodities, inconsistency of global polices on AFs permissible concentration in food/feed, and lack of the public awareness are accounting for a considerable proportion of AFs damages. AFs exhibited their toxic effects by triggering the progression of inflammation and oxidative/nitrosative stress, in turn, leading to the onset of nCDs. PPs could decrease AFs-associated oxidative stress, genotoxic, mutagenic, and carcinogenic effects by improving cellular antioxidant balance, regulation of signaling pathways, alleviating inflammatory responses, and modification of gene expression profile in a dose/time-reliant fashion. The administration of PPs alone displayed lower biological properties compared to co-treatment of these metabolites with AFs. This issue might highlight the therapeutic application of PPs than their preventative content. Flavonoids such as quercetin and oxidized tea phenolics, curcumin and resveratrol were the most studied anti-AFs PPs. Our literature review clearly disclosed that considering PPs in antioxidant therapies to alleviate complications of AFs requires improvement in their bioavailability, pharmacokinetics, tissue clearance, and off-target mode of action. Due to the emergencies in the elimination of AFs in food/feedstuffs, further large-scale clinical assessment of PPs to decrease the consequences of AFs is highly required.

16.
Int J Biol Macromol ; 219: 1100-1111, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36049563

ABSTRACT

Disease-related tau protein in Alzheimer's disease is hyperphosphorylated and aggregates into neurofibrillary tangles. The cis-proline isomer of the pSer/Thr-Pro sequence has been proposed to act as a precursor of aggregation ('Cistauosis' hypothesis), but this aggregation scheme is not yet entirely accepted. Hence to investigate isomer-specific-aggregation of tau, proline residues at the RTPPK motif were replaced by alanine residues (with permanent trans configuration) employing genetic engineering methods. RTPAK, RTAPK, and RTAAK mutant variants of tau were generated, and their in vitro aggregation propensity was investigated using multi-spectroscopic techniques. Besides, the cell toxicity of oligomers/fibrils was analyzed and compared to those of the wild-type (WT) tau. Analyses of mutant variants have shown to be in agreement (to some degree) to the theory of the 'cistauosis' hypothesis. The results showed that the trans isomer in the 232-rd residue (P232A mutant rather than P233A) had reduced aggregation propensity. However, this study did not illustrate any statistically significant difference between the wild and the mutant protein aggregations concerning cell toxicity.


Subject(s)
Alzheimer Disease , tau Proteins , Alanine , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Humans , Mutant Proteins , Proline/chemistry , Protein Aggregates , tau Proteins/chemistry
17.
Eur J Neurol ; 29(12): 3647-3657, 2022 12.
Article in English | MEDLINE | ID: mdl-36048129

ABSTRACT

BACKGROUND AND PURPOSE: There is some evidence that cytokines may play an important role in sleep deprivation; however, the underlying mechanisms are still unknown. So, the present study aimed to evaluate the relationship between NOD-like receptor protein 1 (NLRP1) and NOD-like receptor protein 3 (NLRP3) inflammasome activation of blood cells and serum levels of cytokines in individuals with chronic insomnia disorder (CID). METHODS: Blood samples were collected from 24 individuals with CID and 24 healthy volunteers. The inflammasome activation was evaluated using real-time polymerase chain reaction of NLRP1, NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) and caspase-1; western blot of NLRP1 and NLRP3; caspase-1 activity assay; and serum levels of interleukin-1ß (IL-1ß), IL-18 and other cytokines using enzyme-linked immunosorbent assay. Reactive oxygen species generation in blood cells were detected by flow cytometry assay. Also, magnetic resonance imaging scans were obtained on a Siemens Magnetom Avanto 1.5 T MRI whole-body scanner using an eight-channel head coil. RESULTS: Increased activity of NLRP1 and NLRP3 inflammasomes in blood cells, increased serum levels of pro-inflammatory cytokines and decreased serum levels of IL-10 and transforming growth factor ß in individuals with CID were found. Significant correlation was observed between increased serum concentration of IL-1ß and the severity of insomnia in individuals with CID. The levels of reactive oxygen species in blood cells were found to be correlated with IL-1α and tumor necrosis factor α concentrations in sera from individuals with CID. Moreover, the individuals with CID demonstrated increased right cerebellum cortex and lateral ventricle mean diffusivity bilaterally compared to controls. CONCLUSIONS: This study provided new insights on the pathogenesis of CID and the effects of cytokines on inflammasome activation.


Subject(s)
Inflammasomes , Sleep Initiation and Maintenance Disorders , Humans , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha , NLR Proteins , Interleukin-1alpha , Caspase 1/metabolism , Oxygen
18.
J Fluoresc ; 32(5): 1733-1741, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35675001

ABSTRACT

In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis) detection. For this purpose, water-soluble synthesized CDs were functionalized with 19 mer-modified oligonucleotides (capture probe). By adding the DNA target, the specific binding between the DNA probe and DNA target causes fluorescence quenching. The assay displayed a fine capability of sensing the BRCA1 gene with a linear range (R2 = 0.9918) of 36 attomolar (aM) to 532 femtomolar (fM) and a detection limit of 2 attomolar. This homogeneous process does not need additional separation and washing steps of un-hybridized DNA. To assess the selectivity, the prepared biosensor responses were evaluated in solutions containing single-base mismatched DNA sequences, three-base mismatched DNA sequences, or non-complementary DNA sequences, separately. To demonstrate the practical application of the designed biosensor, the extracted DNA from blood samples of breast cancer patients was utilized as real samples. When the CDs-DNA bioassay was exploited in the imaging of MCF-7 cancer cells, strong fluorescence emission was observed. After incubation times, both the cells' size and shape remained unchanged. The results validated that the CDs are an extremely great bioimaging candidate in disease diagnosis, biomedicine investigation, and managing cancer diseases.


Subject(s)
Breast Neoplasms , Quantum Dots , BRCA1 Protein/genetics , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/genetics , Carbon , DNA/genetics , Female , Fluorescent Dyes , Genes, BRCA1 , Humans , Spectrometry, Fluorescence/methods
19.
Med Chem ; 19(1): 99-117, 2022.
Article in English | MEDLINE | ID: mdl-35579152

ABSTRACT

BACKGROUND: Over the past twenty years, the prevalence of diabetes as one of the most common metabolic diseases has become a public health problem worldwide. Blood glucose control is important in delaying the onset and progression of diabetes-related complications. α-Glycosidase (α- Glu) and α-amylase (α-Amy) are important enzymes in glucose metabolism. Diabetic control through the inhibition of carbohydrate hydrolyzing enzymes is established as an effective strategy. METHODS: In this study, curcumin-based benzaldehyde derivatives with high stability, bioavailability, and favorable efficiency were synthesized. RESULTS: The results showed that L13, L8, and L11 derivatives have the highest inhibitory effect on α-Glu with IC50 values of 18.65, 20.6, and 31.7 µM and, also L11, L13, and L8 derivatives have the highest inhibitory effect on α-Amy with IC50 value of 14.8, 21.8, and 44.9 µM respectively. Furthermore, enzyme inhibitory kinetic characterization was also performed to understand the mechanism of enzyme inhibition. CONCLUSION: L13, compared to the other compounds, exhibited acceptable inhibitory activity against both enzymes. The L13 derivative could be an appropriate candidate for further study through the rational drug design to the exploration of a new class of powerful anti-diabetic drugs considering the antioxidant properties of the synthesized compounds. The derivative helps reduce the glycemic index and limits the activity of the major reactive oxygen species (ROS) producing pathways.


Subject(s)
Curcumin , Diabetes Mellitus , Humans , Hypoglycemic Agents/pharmacology , Curcumin/pharmacology , alpha-Amylases , alpha-Glucosidases/metabolism , Glycoside Hydrolase Inhibitors/pharmacology , Molecular Docking Simulation
20.
BMC Infect Dis ; 22(1): 319, 2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35361161

ABSTRACT

BACKGROUND: Since the first official report of SARS-CoV-2 infection in Iran on 19 February 2020, our country has been one of the worst affected countries by the COVID-19 epidemic in the Middle East. In addition to demographic and clinical characteristics, the number of hospitalized cases and deaths is an important factor for evidence-based decision-making and disease control and preparing the healthcare system to face the future challenges of COVID-19. Therefore, this cohort study was conducted to determine the demographics, clinical characteristics, and outcomes of hospitalized COVID-19 patients in Kermanshah Province, west of Iran. METHODS: This multicenter retrospective cohort study included all suspected, probable, and confirmed cases of COVID-19 hospitalized in Kermanshah Province, Iran during the first year of the COVID-19 pandemic. Demographics, clinical characteristics, outcomes and other additional information of hospitalized patients were collected from the COVID-19 database of the Medical Care Monitoring Center (MCMC) of Kermanshah Province. RESULTS: Kermanshah Province experienced three waves of COVID-19 infection considering the hospitalization and mortality rates between February 20, 2020 and February 19, 2021. A total of 27,256 patients were included in the study: 5203 (19.09%) subjects were suspected, 9136(33.52%) were probable, and 12,917 (47.39%) were confirmed COVID-19 cases. The mean age of the patients was 53.34 ± 22.74 years and 14,648 (53.74%) were male. The median length of hospital stay among COVID-19 survivors and non-survivors patients were 4 (interquartile range [IQR] 1-6) and 4 (IQR 1-8) days, respectively. Among patients with COVID-19, 2646 (9.71%) died during hospitalization. A multivariable logistic regression revealed that odds of death among patients ≥ 85 years was significantly greater than among patients < 15 years (adjusted odds ratio [aOR] 4.79, 95% confidence interval [CI] = 3.43-6.71, p≤ 0.001). Patients with one (aOR 1.38, 95% CI 1.21-1.59, p = 0.04), two (aOR 1.56, 95% CI 1.27-1.92, p = 0.001) or more (aOR 1.50, 95% CI 1.04-2.17, p = 0.03) comorbidities had higher odds of in-hospital death compared to those without comorbidities. The male sex (aOR 1.20, 95% CI 1.07- 1.35, p = 0.002), ICU admission (aOR 4.35, 95% CI 3.80-4.97, p < 0.001), intubation (aOR 11.09, 95% CI 9.58-12.84, p < 0.001), respiratory distress (aOR 1.40, 95% CI 1.22-1.61, p < 0.001), loss of consciousness (aOR 1.81, 95% CI 1.45-2.25, p < 0.001), anorexia (aOR 1.36, 95% CI 1.09-1.70, p = 0.006) and peripheral oxygen saturation (SpO2) < 93(aOR 2.72, 95% CI 2.34-3.16, p < 0.001) on admission were associated with increased risk of death in patients with SARS-CoV-2 infection. Having cough (aOR 0.82, 95% CI 0.72-0.93, p = 0.003) and headache (aOR 0.70, 95% CI 0.50-0.97, p = 0.03) decreased the odds of death. CONCLUSION: The mortality rate of the patients admitted to the general wards and ICU can be a guide for allocating resources and making appropriate plans to provide better medical interventions during the COVID-19 pandemic. Several risk factors are associated with the in-hospital mortality of COVID-19, including advanced age, male sex, ICU admission, intubation, having comorbidity, SpO2 < 93, respiratory distress, loss of consciousness, headache, anorexia, and cough. These risk factors could help clinicians identify patients at high risk for death.


Subject(s)
COVID-19 , Adult , Aged , COVID-19/epidemiology , COVID-19/therapy , Cohort Studies , Hospital Mortality , Humans , Iran/epidemiology , Male , Middle Aged , Pandemics , Retrospective Studies , SARS-CoV-2
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