Catharanthus roseus-assisted bio-fabricated zinc oxide nanoparticles for promising antibacterial potential against Klebsiella pneumoniae.

This study emphasized on the synthesis of zinc oxide nanoparticles (ZnO NPs) in an environmentally friendly manner from the extract of Catharanthus roseus leaves and its antibacterial assessment against the pneumonia-causing pathogen Klebsiella pneumoniae. This simple and convenient phytosynthesis approach is found to be beneficial over conventional methods, wherein plants serve as excellent reducing, capping, and stabilizing agents that enables the formation of ZnO NPs without the use of harmful chemicals. The formation of ZnO NPs was confirmed through several characterization techniques such as UV-visible spectroscopy, XRD, FT-IR, SEM, HR-TEM, and EDX. XRD analysis revealed high polycrystallinity with crystallite size of approximately 13 nm. SEM and HR-TEM revealed the hexagonal structure of ZnO NPs with the particle size range of 20-50 nm. The EDX shows the elemental purity without any impurity. Furthermore, the antibacterial efficacy by the technique of disc diffusion exhibited clear inhibition zones in ZnO NPs-treated discs. In addition, 125 µg/mL of ZnO NP concentration showed minimum inhibition by the microbroth dilution method. The potent inhibitory activity was further validated with trypan blue dye exclusion and fluorescence microscopy. Finally, SEM examination confirmed the efficient antibacterial potential of ZnO NPs through disruption of the intact morphology of Klebsiella pneumoniae.

Green Synthesis of Cerium Oxide Nanoparticles, Characterization, and Their Neuroprotective Effect on Hydrogen Peroxide-Induced Oxidative Injury in Human Neuroblastoma (SH-SY5Y) Cell Line.

Cerium oxide nanoparticles (CeO2NPs) have a broad scale of applications in the biomedical field due to their excellent physicochemical and catalytic properties. The present study aims to synthesize the CeO2NPs from Centella asiatica (C. asiatica) leaf extract, which has been used in Indian traditional medicine for its neuroprotective properties. The CeO2NPs were characterized by ultraviolet-visible, X-ray diffraction, Fourier transform infrared, Raman spectroscopy, scanning electron microscopy- energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy. The antioxidant property was evaluated by 2,2-di (4-tert-octyl phenyl)-1-picrylhydrazyl and OH radical assays. The neuroprotective potential was assessed against the oxidative stress (OS) induced by H2O2 in the human neuroblastoma (SH-SY5Y) cell line. CeO2NPs exhibited significant DPPH and OH radical scavenging activity. Our results revealed that CeO2NPs significantly increased H2O2-induced cell viability, decreased lactate dehydrogenase, protein carbonyls, reactive oxygen species generation, apoptosis, and upregulated antioxidant enzyme activity. Our findings suggest that the CeO2NPs protect the SH-SY5Y cells from OS and apoptosis, which could potentially counter OS-related neurodegenerative disorders.

Trichoderma-Mediated ZnO Nanoparticles and Their Antibiofilm and Antibacterial Activities.

Antimicrobial resistance is a major global health concern and one of the gravest challenges to humanity today. Antibiotic resistance has been acquired by certain bacterial strains. As a result, new antibacterial drugs are urgently required to combat resistant microorganisms. Species of Trichoderma are known to produce a wide range of enzymes and secondary metabolites that can be exploited for the synthesis of nanoparticles. In the present study, Trichoderma asperellum was isolated from rhizosphere soil and used for the biosynthesis of ZnO NPs. To examine the antibacterial activity of ZnO NPs against human pathogens, Escherichia coli and Staphylococcus aureus were used. The obtained antibacterial results show that the biosynthesized ZnO NPs were efficient antibacterial agents against the pathogens E. coli and S. aureus, with an inhibition zone of 3-9 mm. The ZnO NPs were also effective in the prevention of S. aureus biofilm formation and adherence. The current work shows that the MIC dosages of ZnO NPs (25, 50, and 75 µg/mL) have effective antibacterial activity and antibiofilm action against S. aureus. As a result, ZnO NPs can be used as a part of combination therapy for drug-resistant S. aureus infections, where biofilm development is critical for disease progression.

Fabrication and in vitro Evaluation of 4-HIA Encapsulated PLGA Nanoparticles on PC12 Cells.

PURPOSE: 4-Hydroxyisophthalic acid (4-HIA) is a bioactive compound present in the roots of Decalepis hamiltonii, which has attracted considerable attention in attenuating oxidative stress-related neurodegenerative diseases. However, its efficacy is limited because of its low solubility and bioavailability. Therefore, the present study aimed to encapsulate 4-HIA using biocompatible copolymer polylactide-co-glycolide (PLGA) and evaluate its antioxidant and neuroprotective potential. METHODS: The nanoparticles (NPs) were fabricated by solid/oil/water (s/o/w) emulsion technique and characterized using XRD, SEM, HR-TEM, and FTIR spectroscopy. Antioxidant assays such as 1,1 diphenyl-2-picrylhydrazyl (DPPH), superoxide, and hydroxyl radical scavenging ability were performed to assess the antioxidant potential of the fabricated NPs. RESULTS: The bioactive component, 4-HIA, was efficiently encapsulated by the PLGA polymer and was found to be spherical and smooth with a size <10nm. 4-HIA showed better scavenging capability in DPPH and superoxide assays as compared to 4-HIA encapsulated PLGA and butylated hydroxytoluene (BHT). In contrast, 4-HIA encapsulated PLGA NPs exhibited a significant hydroxyl radical scavenging activity than 4-HIA and BHT alone. Further, the encapsulated NPs efficiently curtailed hydrogen peroxide (H2O2)-induced cytotoxicity in PC12 cells. CONCLUSION: Our findings indicate that 4-HIA encapsulated PLGA NPs might be a therapeutic intervention towards the effective management of oxidative stress as it has exhibited efficient neuroprotective potential against H2O2-induced oxidative stress in PC12 cells.

Modulatory Effects of Decalepis hamiltonii Extract and Its Compounds on the Antioxidant Status of the Aging Rat Brain.

OBJECTIVE: The present study was aimed to investigate the neuroprotective effects of Decalepis hamiltonii (Dh) aqueous root extract and its compounds against age-related oxidative stress (OS) in the discrete regions of the rat brain. MATERIALS AND METHODS: Male Wistar albino rats of 4- and 22-month-old were divided into control and six supplemented groups. The supplemented groups were orally administered with ellagic acid (EA), 4-hydroxyisophthalic acid (4-HIA), and Dh extract for 30 days. RESULTS: Age-related decrease in antioxidant enzyme activities was noticed. The hippocampus was found to be more vulnerable to OS as seen by the elevation in the OS markers. Supplementation of the Dh extract, EA, and 4-HIA was found to be effective in up-regulating the antioxidant status. However, the extent of up-regulation was more evident in Dh supplemented animals. CONCLUSION: Our results suggest that Dh extract and its compounds exhibit neuroprotective effects against age-related OS and can be used as a dietary therapeutic intervention for the treatment of neurological disorders.

Age-related changes in the brain antioxidant status: modulation by dietary supplementation of Decalepis hamiltonii and physical exercise.

The synergistic effects of physical exercise and diet have profound benefits on brain function. The present study was aimed to determine the effects of exercise and Decalepis hamiltonii (Dh) on age-related responses on the antioxidant status in discrete regions of rat brain. Male Wistar albino rats of 4 and 18 months old were orally supplemented with Dh extract and swim trained at 3 % intensity for 30 min/day, 5 days/week, for a period of 30 days. Supplementation of 100 mg Dh aqueous extract/kg body weight and its combination with exercise significantly elevated the antioxidant enzyme activities irrespective of age. Age-related and region-specific changes were observed in superoxide levels, and protein carbonyl and malondialdehyde contents, and were found to be decreased in both trained and supplemented groups. Levels of total thiols, protein, and nonprotein thiols decreased with age and significantly increased in the SW-T(+100 mg) groups. Our results demonstrated that the interactive effects of two treatments enhanced the antioxidant status and decreased the risk of protein and lipid oxidation in the rat brain.

Differential expression of the cerebral cortex proteome in physically trained adult rats.

Exercise has beneficial effects on brain function, including the promotion of plasticity and the enhancement of learning and memory performance. To further explore the molecular changes in the protein expression levels in the cerebral cortex of physically trained rats, male Wistar rats 8 months old were selected and subjected to swimming training in a rectangular glass tank for 30 min/day, 6 days/week and 3% of load for 4 weeks. Two dimensional gel electrophoresis followed by mass spectrometrical identification assigning spots to proteins and determination of coomassie-densities of the protein spots were carried out. The up-regulated spots were found to be statistically significant with a p-value of <0.05. Proteins related to energy metabolism like GAPDH and ATP synthase and synaptic plasticity related proteins like actin, tubulin and 14-3-3 zeta/delta were up-regulated in the cerebral cortex of swim trained rats. Thus, our results suggest that exercise elicits a differential protein expression pattern with significant changes in proteins relevant to cortical function and these proteins may be incorporated with neuronal recovery in terms of neurite formation and remodeling of synaptic connections.

Influence of Punica granatum L. on region specific responses in rat brain during Alloxan-Induced diabetes

Objective: The present study was carried out to investigate the effects of Punica granatum peel methanolic extract (PGPE) on cerebral cortex (CC) and Hippocampus (HC) brain antioxidant defense system and markers of lipid and protein oxidation in alloxan induced diabetic rats.Methods:Oral administration of PGPE (75 and 150 mg of kg body weight) for 45 days resulted in significant reduction in blood glucose levels. Results: Supplementation of diabetic rats with PGPE showed increased activities of SOD and GPx with concomitant decrease in MDA and PC content. Region-specific changes were more evident in the HC when compared to CC. Conclusions: The present study indicated that PGPE can ameliorate brain oxidative stress in alloxan induced diabetic rats by up regulating antioxidant defense mechanism by attenuating lipid and protein oxidation. PGPE thus may be used as a potential therapeutic agent in preventing diabetic complications in the brain.