Mumtaz, S. | Search bioRxiv

bioRxiv2021

Cardiorespiratory fitness predicts cortical thickness of medial temporal brain areas associated with spatial cognition in young but not older adults

Cardiorespiratory fitness (CRF) has been shown to have a potent effect on neurocognitive health. However, less is known about the impact of CRF on extrahippocampal neocortical regions in the medial temporal lobes (MTL). Specifically, it is unclear whether CRF modulates these MTL regions in young adulthood and if these brain areas are differentially related to CRF in young vs. older adults. The primary goal of the current study was to investigate if CRF predicted cortical thickness of MTL neocortical regions that, along with the hippocampus, are critical for spatial learning and memory. Additionally, given the established role of the MTL cortices in spatial navigation, we sought to determine if CRF and MTL cortical thickness would predict greater subjective sense of direction in both young and older adults. Cross-sectional data from 56 young adults (20-35 years) and 44 older adults (55-85 years) were included. Using hierarchical multiple regression analyses, we confirmed significant positive relationships between greater CRF and greater left entorhinal, left parahippocampal, and left perirhinal cortical thickness in young, but not older, adults. Left parahippocampal thickness interacted with age group to differentially predict sense of direction in young and older adults. Young adults displayed a positive, and older adults a negative, relationship between left parahippocampal thickness and sense of direction. Our findings extend previous work on the association between CRF and hippocampal subfield structure in young adulthood to left MTL neocortical regions. HighlightsO_LICardiorespiratory fitness assessed in young and older adults using a submaximal treadmill test. C_LIO_LISurface-based structural analysis of cortical thickness of medial temporal regions. C_LIO_LICardiorespiratory fitness predicted left medial temporal cortical thickness in young but not older adults. C_LIO_LILeft parahippocampal thickness differentially predicted sense of direction in young and older adults. C_LI

neuroscience↗

bioRxiv2020

Evaluation of Antimicrobial, Antioxidant, Total Phenolic, Total Flavonoids, Metal Content and Proximate Potential of Solanum xanthocarpum L. (Solanaceae)

The current research work is focused on screening of antimicrobial, antioxidant, total phenolic, total flavonoid, metal estimation and proximate potential of four parts (fruits, leaves, stem bark and root bark) of S. xanthocarpum. Antimicrobial potential of dried crude extracts of S. xanthocarpum were evaluated against two gram positive bacteria (S. aureus, P. vulgaris), three gram negative bacteria (P. aeruginosa, K. pneumonia, E. coli), three fungi (A. flavus, F. solani, stolonifer) and two yeasts (S. cerevisiae, C. albicans) by using disc diffusion assay. Five organic solvents ranging from non-polar to highly polar were used for extraction of active metabolites. Amongst all the parts of S. xanthocarpum tested, antimicrobial activity of methanol extract of fruits (14.67{+/-}0.33) against P. aeruginosa, ethanolic extract of leaves against P. vulgaris (14{+/-}0.58), stem bark methanolic extract against S. aureus (13{+/-}0.58) and stem bark methanolic extract against P. vulgaris (17.67{+/-}0.33) were found to be more significant. All other extracts also showed promising antimicrobial activity against bacterial pathogens. Among fungal pathogens, R. stolonifer and S. cerevisiae were found to be more sensitive to extracts of S. xanthocarpum. Gram negative bacteria exhibited more resistance than gram positive bacteria. However, fungi were found to be more resistant than bacteria. All the extracts showed antioxidant activity. However, methanol extract of stem bark of S. xanthocarpum with IC50 value of 0.323102 mg mL-1 showed maximum antioxidant potential. Total phenolic contents ranged from 12.3541{+/-}1.73 to 23.2942{+/-}1.33 Pmol GA/ug. However, highest flavonoid content was found in the stem bark extract (17.8480{+/-}1.75 ugRutin/ug) and lowest in leaves extract of S. xanthocarpum (2.4806{+/-}0.59 ugRutin/ug). Total metal contamination in four parts of Solanum xanthocarpum (fruits, leaves, stem bark and root bark) was estimated by atomic absorption spectroscopy and results showed Cadmium contamination in its stem bark and root bark, Chromium contamination in leaves, stem bark and root bark, Copper and Magnesium contamination in all parts of S. xanthocarpum and Maganese contamination in leaves critically above the standard permissible limits. The proximate analysis of the Solanum xanthocarpum revealed that stem bark is a poor source of lipid (3.42%) and high carbohydrate (50.07%) and ash (16.50%) contents. Whereas, root bark has highest wet moisture content (65%), dry moisture content (20%) and lowest fiber (13%). Highest energy (285.455%), protein (8.32%), fat (9.79%) and lowest amount of ash (13%) was found in fruits. This composition shows that the Solanum xanthocarpum could be considered as a good source of carbohydrate, moisture and energy. These results revealed that over all, methanolic extract of the S. xanthocarpum is richest in phenolic, flavonoid and nutritional contents as well as most potent against bacterial and fungal pathogens. Therefore, further investigation is recommended to isolate, screen and characterize their active metabolites.

plant biology↗