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Hou, M.

Publications and source records attributed to Hou, M..

40 records · Page 3Linked to original sources

One viral sequence for each host? - The neglected within-host diversity as the main stage of SARS-CoV-2 evolution

The standard practice of presenting one viral sequence for each infected individual implicitly assumes low within-host genetic diversity. It places the emphasis on the viral evolution between, rather than within, hosts. To determine this diversity, we collect SARS-CoV-2 samples from the same patient multiple times. Our own data in conjunction with previous reports show that two viral samples collected from the same individual are often very different due to the substantial within-host diversity. Each sample captures only a small part of the total diversity that is transiently and locally released from infected cells. Hence, the global SARS-CoV-2 population is a meta-population consisting of the viruses in all the infected hosts, each of which harboring a genetically diverse sub-population. Advantageous mutations must be present first as the within-host diversity before they are revealed as between-host polymorphism. The early detection of such diversity in multiple hosts could be an alarm for potentially dangerous mutations. In conclusion, the main forces of viral evolution, i.e., mutation, drift, recombination and selection, all operate within hosts and should be studied accordingly. Several significant implications are discussed.

evolutionary biology↗

FGF2 disruption enhances thermogenesis in brown and beige fat to protect against obesity and hepatic steatosis

Since brown and beige fat expend energy in the form of heat via non-shivering thermogenesis, identifying key regulators of thermogenic functions represents a major goal for development of potential therapeutic avenues for obesity and associated disorders. Here, we identified fibroblast growth factor 2 (FGF2) as a novel thermogenic regulator. FGF2 gene disruption resulted in increased thermogenic capability in both brown and beige fat, which was supported by increased UCP1 expression, enhanced respiratory exchange ratio, and elevated thermogenic potential under cold challenge or {beta}-adrenergic stimulation. Thus, deletion of FGF2 protected mice from high fat-induced obesity and hepatic steatosis. Mechanistically, FGF2 acts in autocrine/paracrine fashions in vitro. Exogenous FGF2 supplementation inhibits both PGC-1 and PPAR{gamma} expression through ERK phosphorylation, thereby limiting PGC-1/PPAR{gamma} interactions, and leading to suppression of UCP1 expression and thermogenic activity in brown and beige adipocytes. These findings suggest a viable potential strategy for use of FGF2-selective inhibitors in treatment of combating obesity and related disorders.

cell biology↗

High-Fiber Diet Restores Maternal Obesity-Induced Cognitive and Social Behavioral Deficits in Offspring via Regulating Gut Microbiota-Metabolites-Brain Axis

Maternal obesity has been reported to be related to the neurodevelopmental disorders in offspring. However, the underlying mechanisms and effective interventions remain unclear. Here, a cross-sectional study on 778 children aged 7-14 years in two cities of China indicates that the maternal obesity is highly associated with the poorer cognition and sociality of their children. Moreover, we also find that the maternal obesity in mice disrupts the behavior and the gut microbiome in the offspring, which are alleviated by a high-fiber diet in either dams or offspring. Co-housing and feces microbiota transplantation experiments reveal a causal relationship between the reshaped microbiota and the behavioral changes. Moreover, treatment of the microbiota-derived short-chain fatty acids exhibits a similar beneficial effect on alleviating the behavioral deficits in offspring. Together, our study purports the microbiota-metabolites-brain axis as a mechanism, and high-dietary fiber intake is a promising intervention against maternal obesity-induced cognitive and social dysfunctions.

neuroscience↗

Recollection-related hippocampal fMRI effects predict longitudinal memory change in healthy older adults

Prior fMRI studies have reported relationships between memory-related activity in the hippocampus and in-scanner memory performance, but whether such activity is predictive of longitudinal memory change remains unclear. Here, we administered a neuropsychological test battery to a sample of cognitively healthy older adults on three occasions, the second and third sessions occurring one month and three years after the first session. Structural and functional MRI data were acquired between the first two sessions. The fMRI data were derived from an associative recognition procedure and allowed estimation of hippocampal effects associated with both successful associative encoding and successful associative recognition (recollection). Baseline memory performance and memory change were evaluated using memory component scores derived from a principal components analysis of the neuropsychological test scores. Across participants, right hippocampal encoding effects correlated significantly with baseline memory performance after controlling for chronological age. Additionally, both left and right hippocampal associative recognition effects correlated significantly with longitudinal memory change after controlling for age, and the relationship with the left hippocampal effect remained after also controlling for left hippocampal volume. Thus, in cognitively healthy older adults, the magnitude of hippocampal recollection effects appears to be a robust predictor of future memory change.

neuroscience↗