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Rossiter, H. B.

Publications and source records attributed to Rossiter, H. B..

2 recordsLinked to original sources

Paternal Metabolic Reversal Remodels Sperm RNA Profiles and Ameliorates Intergenerational Metabolic Disorder in Mice

Paternal obesity increases metabolic risk in offspring, but whether this risk can be reduced by restoring paternal health before conception remains unresolved. We developed a within-sire induction-and-reversal model in outbred CD1 mice in which high-fat diet (HFD)-exposed males generated offspring before and after transition to an ingredient-matched control diet with voluntary exercise. HFD caused obesity, glucose intolerance, insulin resistance, and extensive remodeling of sperm mRNA, lncRNA, and sncRNA profiles, together with transcriptomic changes in metabolic tissues. Diet and exercise reversal normalized paternal metabolic indices and broadly restored tissue RNA profiles, although sperm retained a limited transcriptional memory of prior HFD exposure. Offspring sired before reversal developed sex-dependent metabolic dysfunction despite control-diet rearing, whereas offspring sired after reversal showed substantial improvement. These findings show that paternal metabolic risk is modifiable before conception and that this reversibility is linked to remodeling of sperm RNA. (140 words) HighlightsO_LIPaternal HFD-Ex induces obesity, glucose intolerance and insulin resistance in CD1 males C_LIO_LISperm shows much stronger RNA response than four metabolic organs profiled C_LIO_LIDiet and exercise reversal restores metabolism and RNA profiles in sperm and four metabolic organs analyzed C_LIO_LIOffspring metabolic risk is reduced when sires conceive after reversal through diet and exercise intervention C_LI eTOC BlurbChen, Magalhaes, et al. show that paternal metabolic recovery before conception remodels sperm RNA and reduces transmission of HFD-associated metabolic risk to offspring in a within-sire mouse model.

genetics↗

Tissue-specific dysregulation of mitochondrial respiratory capacity and coupling control in colon-26 tumor-induced cachexia

In addition to skeletal muscle dysfunction, recent frameworks describe cancer cachexia as a systemic disease involving remodeling of non-muscle organs such as adipose and liver. Impairment of mitochondrial function is associated with multiple diseases. The tissue-specific control of mitochondrial function in cancer cachexia is not well-defined. This study determined mitochondrial respiratory capacity and coupling control of skeletal muscle, white adipose tissue (WAT), and liver in colon-26 (C26) tumor-induced cachexia. Tissues were collected from PBS-injected weight-stable mice, C26 mice that were weight-stable, and C26 mice with moderate (10% weight loss) and severe cachexia (20% weight loss). WAT showed high non-phosphorylating LEAK respiration and reduced respiratory control ratio (RCR, index of OXPHOS coupling efficiency) during the induction of cachexia. Liver RCR decreased early due to cancer, and further declined with severe cachexia, where Ant2 but not Ucp2 expression was increased. Ant2 also related inversely with RCR in the liver (r=-0.547, p<0.01), suggesting a role for Ant2 in uncoupling of liver OXPHOS. Increased liver cardiolipin occurred during moderate cachexia and remained elevated in severe cachexia, suggesting this early event may also contribute to uncoupling. Impaired skeletal muscle mitochondrial respiration occurred predominantly in severe cachexia. These findings suggest that mitochondrial function is subject to tissue-specific control during cancer cachexia, whereby remodeling in WAT and liver arise early and could contribute to altered energy balance, followed by impaired skeletal muscle respiration. We highlight an underrecognized role of liver mitochondria in cancer cachexia, and suggest mitochondrial function of multiple tissues to be targets for therapeutic intervention.

physiology↗