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1.
Neurochem Res ; 49(1): 52-65, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37597050

RESUMEN

Increased oxidative stress and acetylcholinesterase (AChE) activity are key pathological characters contributing to the memory disorders. Thus, drugs targeting both oxidative stress and AChE are being explored for the management of cognitive dysfunction. Morus alba fruits (commonly consumed for its high nutritious value) are known to have antioxidant and AChE inhibitory effects. However, the role of Morus alba fruits in the management of memory disorders has not reported yet. This investigation was conducted to assess the antioxidant and AChE inhibitory potential of Morus alba fruit extracts in-vitro and to identify the components responsible for such effects. Further, the obtained bioactive component was studied for possible memory improvement effects against streptozotocin (STZ) induced dementia. To isolate the bioactive component in-vitro DPPH and AChE assays guided fractionation was performed. Memory functions in mice were determined using Morris Water Maze test while brain biochemical parameters were measured to understand the mechanism of action. In-vitro assays revealed strong AChE and DPPH inhibitory potential of methanol extract (ME), therefore, it was further fractionated. Among various fractions obtained, ethyl-acetate fraction (EAF) was found to possess marked AChE and DPPH inhibitory activities. On subsequent fractionation of EAF, bioactivity of obtained sub-fractions was found to be inferior to EAF. Further, both ME and EAF improved STZ (intracerebroventricular) induced cognitive dysfunction in animals by restoring endogenous antioxidant status (superoxide dismutase and reduced glutathione) and reducing thiobarbituric acid reactive species and nitric oxide levels along with brain AChE and myeloperoxidase activity. TLC densitometric studies showed appreciable levels of phenolic acids and quercetin in both EAF and ME. It can be concluded that Morus alba fruit extract has the ability to modulate cholinergic and oxidative system due to presence of phenolic and flavonoid compounds and hence, could aid in the management of memory disorders.


Asunto(s)
Antioxidantes , Disfunción Cognitiva , Ratones , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Estreptozocina/toxicidad , Frutas/química , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Acetilcolinesterasa/metabolismo , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/tratamiento farmacológico , Trastornos de la Memoria/inducido químicamente , Estrés Oxidativo , Cognición , Colinérgicos/efectos adversos , Colinérgicos/análisis , Aprendizaje por Laberinto
2.
Arch Microbiol ; 206(5): 236, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38676717

RESUMEN

Lignocellulolytic enzymes from a novel Myceliophthora verrucosa (5DR) strain was found to potentiate the efficacy of benchmark cellulase during saccharification of acid/alkali treated bagasse by ~ 2.24 fold, indicating it to be an important source of auxiliary enzymes. The De-novo sequencing and analysis of M. verrucosa genome (31.7 Mb) revealed to encode for 7989 putative genes, representing a wide array of CAZymes (366) with a high proportions of auxiliary activity (AA) genes (76). The LC/MS QTOF based secretome analysis of M. verrucosa showed high abundance of glycosyl hydrolases and AA proteins with cellobiose dehydrogenase (CDH) (AA8), being the most prominent auxiliary protein. A gene coding for lytic polysaccharide monooxygenase (LPMO) was expressed in Pichia pastoris and CDH produced by M. verrucosa culture on rice straw based solidified medium were purified and characterized. The mass spectrometry of LPMO catalyzed hydrolytic products of avicel showed the release of both C1/C4 oxidized products, indicating it to be type-3. The lignocellulolytic cocktail comprising of in-house cellulase produced by Aspergillus allahabadii strain spiked with LPMO & CDH exhibited enhanced and better hydrolysis of mild alkali deacetylated (MAD) and unwashed acid pretreated rice straw slurry (UWAP), when compared to Cellic CTec3 at high substrate loading rate.


Asunto(s)
Biomasa , Proteínas Fúngicas , Genoma Fúngico , Lignina , Saccharomycetales , Sordariales , Lignina/metabolismo , Sordariales/genética , Sordariales/enzimología , Sordariales/metabolismo , Hidrólisis , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deshidrogenasas de Carbohidratos/metabolismo , Deshidrogenasas de Carbohidratos/genética , Celulosa/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Celulasa/metabolismo , Celulasa/genética
3.
Physiol Plant ; 176(5): e14513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39262029

RESUMEN

Pathogenesis-related proteins (PR), including osmotins, play a vital role in plant defense, being activated in response to diverse biotic and abiotic stresses. Despite their significance, the mechanistic insights into the role of osmotins in plant defense have not been extensively explored. The present study explores the cloning and characterization of the osmotin gene (WsOsm) from Withania somnifera, aiming to illuminate its role in plant defense mechanisms. Quantitative real-time PCR analysis revealed significant induction of WsOsm in response to various phytohormones e.g. abscisic acid, salicylic acid, methyl jasmonate, brassinosteroids, and ethrel, as well as biotic and abiotic stresses like heat, cold, salt, and drought. To further elucidate WsOsm's functional role, we overexpressed the gene in Nicotiana tabacum, resulting in heightened resistance against the Alternaria solani pathogen. Additionally, we observed enhancements in shoot length, root length, and root biomass in the transgenic tobacco plants compared to wild plants. Notably, the WsOsm- overexpressing seedlings demonstrated improved salt and drought stress tolerance, particularly at the seedling stage. Confocal histological analysis of H2O2 and biochemical studies of antioxidant enzyme activities revealed higher levels in the WsOsm overexpressing lines, indicating enhanced antioxidant defense. Furthermore, a pull-down assay and mass spectrometry analysis revealed a potential interaction between WsOsm and defensin, a known antifungal PR protein (WsDF). This suggests a novel role of WsOsm in mediating plant defense responses by interacting with other PR proteins. Overall, these findings pave the way for potential future applications of WsOsm in developing stress-tolerant crops and improving plant defense strategies against pathogens.


Asunto(s)
Defensinas , Regulación de la Expresión Génica de las Plantas , Nicotiana , Proteínas de Plantas , Plantas Modificadas Genéticamente , Estrés Fisiológico , Withania , Withania/genética , Withania/fisiología , Withania/metabolismo , Withania/efectos de los fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/fisiología , Nicotiana/efectos de los fármacos , Nicotiana/microbiología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Estrés Fisiológico/genética , Defensinas/genética , Defensinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Alternaria/fisiología , Sequías , Plantones/genética , Plantones/fisiología , Plantones/efectos de los fármacos , Ácido Salicílico/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Peróxido de Hidrógeno/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Raíces de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/fisiología
4.
Appl Microbiol Biotechnol ; 108(1): 444, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167166

RESUMEN

The current study is the first to describe the temporal and differential transcriptional expression of two lytic polysaccharide monooxygenase (LPMO) genes of Rasamsonia emersonii in response to various carbon sources. The mass spectrometry based secretome analysis of carbohydrate active enzymes (CAZymes) expression in response to different carbon sources showed varying levels of LPMOs (AA9), AA3, AA7, catalase, and superoxide dismutase enzymes pointing toward the redox-interplay between the LPMOs and auxiliary enzymes. Moreover, it was observed that cello-oligosaccharides have a negative impact on the expression of LPMOs, which has not been highlighted in previous reports. The LPMO1 (30 kDa) and LPMO2 (47 kDa), cloned and expressed in Pichia pastoris, were catalytically active with (kcat/Km) of 6.6×10-2 mg-1 ml min-1 and 1.8×10-2 mg-1 ml min-1 against Avicel, respectively. The mass spectrometry of hydrolysis products of Avicel/carboxy methyl cellulose (CMC) showed presence of C1/C4 oxidized oligosaccharides indicating them to be Type 3 LPMOs. The 3D structural analysis of LPMO1 and LPMO2 revealed distinct arrangements of conserved catalytic residues at their active site. The developed enzyme cocktails consisting of cellulase from R. emersonii mutant M36 supplemented with recombinant LPMO1/LPMO2 resulted in significantly enhanced saccharification of steam/acid pretreated unwashed rice straw slurry from PRAJ industries (Pune, India). The current work indicates that LPMO1 and LPMO2 are catalytically efficient and have a high degree of thermostability, emphasizing their usefulness in improving benchmark enzyme cocktail performance. KEY POINTS: • Mass spectrometry depicts subtle interactions between LPMOs and auxiliary enzymes. • Cello-oligosaccharides strongly downregulated the LPMO1 expression. • Developed LPMO cocktails showed superior hydrolysis in comparison to CellicCTec3.


Asunto(s)
Oxigenasas de Función Mixta , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Polisacáridos/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Hidrólisis , Celulosa/metabolismo , Regulación Fúngica de la Expresión Génica , Oligosacáridos/metabolismo , Clonación Molecular
5.
Bioprocess Biosyst Eng ; 47(4): 567-582, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38470501

RESUMEN

The present study reports a highly thermostable ß-glucosidase (GH3) from Rasamsonia emersonii that was heterologously expressed in Pichia pastoris. Extracellular ß-glucosidase was purified to homogeneity using single step affinity chromatography with molecular weight of ~ 110 kDa. Intriguingly, the purified enzyme displayed high tolerance to inhibitors mainly acetic acid, formic acid, ferulic acid, vanillin and 5-hydroxymethyl furfural at concentrations exceeding those present in acid steam pretreated rice straw slurry used for hydrolysis and subsequent fermentation in 2G ethanol plants. Characteristics of purified ß-glucosidase revealed the optimal activity at 80 °C, pH 5.0 and displayed high thermostability over broad range of temperature 50-70 °C with maximum half-life of ~ 60 h at 50 °C, pH 5.0. The putative transglycosylation activity of ß-glucosidase was appreciably enhanced in the presence of methanol as an acceptor. Using the transglycosylation ability of ß-glucosidase, the generated low cost mixed glucose disaccharides resulted in the increased induction of R. emersonii cellulase under submerged fermentation. Scaling up the recombinant protein production at fermenter level using temporal feeding approach resulted in maximal ß-glucosidase titres of 134,660 units/L. Furthermore, a developed custom made enzyme cocktail consisting of cellulase from R. emersonii mutant M36 supplemented with recombinant ß-glucosidase resulted in significantly enhanced hydrolysis of pretreated rice straw slurry from IOCL industries (India). Our results suggest multi-faceted ß-glucosidase from R. emersonii can overcome obstacles mainly high cost associated enzyme production, inhibitors that impair the sugar yields and thermal inactivation of enzyme.


Asunto(s)
Eurotiales , beta-Glucosidasa , Hidrólisis , beta-Glucosidasa/química , Biomasa
6.
Artículo en Inglés | MEDLINE | ID: mdl-39249151

RESUMEN

Endophytic fungi, as plant symbionts, produce an elaborate array of enzymes for efficient disintegration of lignocellulosic biomass into constituent monomeric sugars, making them novel source of lignocellulolytic CAZymes with immense potential in future biorefineries. The present study reports lignocellulolytic enzymes production potential of an endophytic halotolerant Penicillium oxalicum strain isolated from Citrus limon, under submerged and solid-state fermentation (SmF & SSF, respectively), in the presence and absence of salt (1 M NaCl). The comparative QTOF-LC/MS-based exoproteome analysis of the culture extracts unveiled differential expression of CAZymes, with the higher abundance of GH6 and GH7 family cellobiohydrolase in the presence of 1 M salt. The strain improvement program, employing cyclic mutagenesis and diploidization, was utilized to develop hyper-cellulase producing mutant strains of P. oxalicum. The enzyme production of the developed strain (POx-M35) was further enhanced through statistical optimization of the culture conditions utilizing glucose mix disaccharides (GMDs) as an inducer. This optimization process resulted in the lignocellulolytic cocktail that contained high titers (U/mL) of endoglucanase (EG) (146.16), cellobiohydrolase (CBHI) (6.99), ß-glucosidase (ß-G) (26.21), xylanase (336.05) and FPase (2.02 U/mL), which were 5.47-, 5.54-, 8.55-, 4.96-, and 4.39-fold higher when compared to the enzyme titers obtained in wild HP1, respectively. Furthermore, the lignocellulolytic cocktails designed by blending secretome produced by mutant POx-M35 with xylanases (GH10 and GH11) derived from Malbranchea cinnamomea resulted in efficient hydrolysis of unwashed acid pretreated (UWAP) rice straw slurry and mild alkali deacetylated (MAD) rice straw. This study underscores the potential of bioprospecting novel fungus and developing an improved strain for optimized production and constitution of lignocellulolytic cocktails that can be an important determinant in advancing biomass conversion technologies.

7.
Neurochem Res ; 48(1): 13-25, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35987974

RESUMEN

Finding an effective cure for Alzheimer's disease has eluded scientists despite intense research. The disease is a cause of suffering for millions of people worldwide and is characterized by dementia accompanied by cognitive and motor deficits, ultimately culminating in the death of the patient. The course of the disease progression has various underlying contributing pathways, with the first and foremost factor being the development and accumulation of aberrant and misfolded proteins exhibiting neurotoxic functions. The impairment of cellular clearance mechanisms adds to their accumulation, resulting in neuronal death. This is where the PROteolysis TArgeting Chimera (PROTAC) technology comes into play, bringing the UPS degradation machinery in the proximity of the target protein for initiating its degradation and clearing abnormal protein debris with unparalleled precision demonstrating an edge over traditional protein inhibitors in many respects. The technology is widely explored in cancer research and utilized in the treatment of various tumors and malignancies, and is now being applied in treating AD. This review explores the application of PROTAC technology in developing lead compounds for managing this deadly disease along with detailing the pieces of evidence justifying its utility and efficacy.


Asunto(s)
Enfermedad de Alzheimer , Neoplasias , Humanos , Enfermedad de Alzheimer/metabolismo , Quimera Dirigida a la Proteólisis , Proteínas/metabolismo , Proteolisis , Ubiquitina-Proteína Ligasas/metabolismo
8.
J Pediatr Hematol Oncol ; 45(7): e885-e891, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526372

RESUMEN

OBJECTIVES: The objectives of this study were to study the spectrum of neurologic complications in children with lymphoreticular malignancy (acute lymphoblastic leukemia, Hodgkin, and non-Hodgkin lymphoma) at diagnosis and during treatment and to determine the etiology of these complications. MATERIALS AND METHODS: In this descriptive cohort study, conducted between November 2018 and March 2020, 204 children with a diagnosis of lymphoreticular malignancy were enrolled. The baseline investigations were done in all the cases. Those who developed neurological symptoms were evaluated with cerebrospinal fluid examination and radiologic and electrophysiologic studies as per indication and were managed according to standard management guidelines. RESULTS: Of the 204 patients, 30 (14.7%) developed neurological complications. The majority of these complications (n=20/30; 87%) occurred during the intensive chemotherapy period. Common complications included acute methotrexate neurotoxicity (n=7), vincristine-induced neurotoxicity (n=7), central nervous system (CNS) relapse (n=4), and posterior reversible encephalopathy syndrome (n=2). L-asparaginase-induced thrombosis (n=1), intramedullary compression syndrome (n=1), CNS infection (n=2), CNS hemophagocytic lymphohistiocytosis (n=1), and steroid-induced myopathy (n=1) were also observed. The complications resolved in 21/30 (70%) patients after receiving appropriate treatment while the neurological complication persisted in 2/30 (6.7%) patients. Three patients (10%) abandoned the treatment, and 4 (13.3%) patients expired. CONCLUSIONS: Neurologic complications in patients with lymphoreticular malignancy are quite variable, having common presenting symptoms but varying imaging abnormalities. By close follow-up and effective treatment, the morbidity and mortality of these complications can be minimized.


Asunto(s)
Síndrome de Leucoencefalopatía Posterior , Leucemia-Linfoma Linfoblástico de Células Precursoras , Niño , Humanos , Estudios de Cohortes , Síndrome de Leucoencefalopatía Posterior/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Asparaginasa
9.
Metab Brain Dis ; 38(5): 1657-1669, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36947332

RESUMEN

Mounting evidence shows that dietary intake of fruits with polyphenols is beneficial to improve impaired memory functions. This study explored the preventive as well as therapeutic effects of diet enriched with Morus alba fruits extract (DEMA) in streptozotocin (STZ) induced mouse model of memory impairment. The study consisted of two facets: one aspect consisted of pretreatment of animals with DEMA for two weeks followed by STZ (i.c.v) intervention and the second phase involved induction of dementia with STZ (i.c.v) followed by treatment with DEMA for 14 days. Cognitive functions of animals were measured by Morris Water Maze test and to delineate the associated mechanism of action, brain biochemical estimations (acetyl-cholinesterase activity, myeloperoxidase activity, thiobarbituric acid reactive species, superoxide dismutase activity, reduced glutathione and nitrite/nitrate) and histopathological studies (haematoxylin and eosin staining) were performed. Pre- and post- treatment with DEMA significantly prevented and attenuated, respectively, the detrimental effects of STZ on mice brain. The results demonstrated that dietary modification, by incorporation of M. alba fruits, reduces the incidence and aids in treatment of memory disorder in mice by reducing central cholinergic activity, decreasing oxidative stress and preventing neurodegeneration.


Asunto(s)
Acetilcolinesterasa , Frutas , Ratones , Animales , Estreptozocina/farmacología , Frutas/metabolismo , Acetilcolinesterasa/metabolismo , Encéfalo/metabolismo , Trastornos de la Memoria/inducido químicamente , Cognición , Estrés Oxidativo , Glutatión/metabolismo , Dieta , Aprendizaje por Laberinto
10.
Molecules ; 28(20)2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37894484

RESUMEN

Neurodegenerative diseases, such as Alzheimer's and Parkinson's, pose a significant global health challenge, emphasizing the need for novel neuroprotective agents. Basil (Ocimum spp.) has been recognized for its therapeutic potential, and numerous studies have reported neuroprotective effects. In this manuscript, we present a computational protocol to extricate the underlying mechanism of action of basil compounds in neuroprotective effects. Molecular docking-based investigation of the chemical interactions between selected bioactive compounds from basil and key neuroprotective targets, including AChE, GSK3ß, γ-secretase, and sirtuin2. Our results demonstrate that basil compound myricerone caffeoyl ester possesses a high affinity of -10.01 and -8.85 kcal/mol against GSK3ß and γ-secretase, respectively, indicating their potential in modulating various neurobiological processes. Additionally, molecular dynamics simulations were performed to explore the protein-ligand complexes' stability and to analyze the bound basil compounds' dynamic behavior. This comprehensive computational investigation enlightens the putative mechanistic basis for the neuroprotective effects of basil compounds, providing a rationale for their therapeutic use in neurodegenerative disorders after further experimental validation.


Asunto(s)
Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Ocimum basilicum , Ocimum basilicum/química , Glucógeno Sintasa Quinasa 3 beta , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Simulación del Acoplamiento Molecular , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo
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