Paternal environmental inputs can influence various phenotypes in offspring, presenting tremendous implications for basic biology and public health and policy. However, which signals function as a nexus to transmit paternal environmental inputs to offspring remains unclear. Here we show that offspring of fathers with inflammation exhibit metabolic disorders including glucose intolerance and obesity. Deletion of a mouse tRNA RNase, Angiogenin (Ang), abolished paternal inflammation-induced metabolic disorders in offspring. Additionally, Ang deletion prevented the inflammation-induced alteration of 5′-tRNA-derived small RNAs (5′-tsRNAs) expression profile in sperm, which might be essential in composing a sperm RNA ‘coding signature’ that is needed for paternal epigenetic memory. Microinjection of sperm 30–40 nt RNA fractions (predominantly 5′-tsRNAs) from inflammatory Ang+/+ males but not Ang–/– males resulted in metabolic disorders in the resultant offspring. Moreover, zygotic injection with synthetic 5′-tsRNAs which increased in inflammatory mouse sperm and decreased by Ang deletion partially resembled paternal inflammation-induced metabolic disorders in offspring. Together, our findings demonstrate that Ang-mediated biogenesis of 5′-tsRNAs in sperm contributes to paternal inflammation-induced metabolic disorders in offspring.

The effect of stress on male fertility is a widespread public health issue, but less is known about the related signaling pathway. To investigate this, we established a hypercortisolism mouse model by supplementing the drinking water with corticosterone for four weeks. In the hypercortisolism mice, the serum corticosterone was much higher than in the control, and serum testosterone was significantly decreased. Moreover, corticosterone treatment induced decrease of sperm counts and increase of teratozoospermia. Increased numbers of multinucleated giant cells and apoptotic germ cells as well as downregulated meiotic markers suggested that corticosterone induced impaired spermatogenesis. Further, upregulation of macrophage‐specific marker antigen F4/80 as well as inflammation‐related genes suggested that corticosterone induced inflammation in the testis. Lactate content was found to be decreased in the testis and Sertoli cells after corticosterone treatment, and lactate metabolism‐related genes were downregulated. In vitro phagocytosis assays showed that the phagocytic activity in corticosterone‐treated Sertoli cells was downregulated and accompanied by decreased mitochondrial membrane potential, while pyruvate dehydrogenase kinase‐4 inhibitor supplementation restored this process. Taken together, our results demonstrated that dysfunctional phagocytosis capacity and lactate metabolism in Sertoli cells participates in corticosterone‐induced impairment of spermatogenesis.

There is growing evidence that paternal environmental information alters small noncoding RNAs (sncRNAs) in sperm and in turn can induce alterations of metabolic and behavioral phenotypes of the next generation. However, the potential mediators of the effects remain to be elucidated. A great diversity of environmental insults and stresses can convergently induce the elevation of reactive oxygen species (ROS) in sperm; nonetheless, it remains unclear whether ROS mediates the biogenesis of sncRNAs in sperm and participates in the reprogramming of offspring phenotypes. Here, we show that ROS could induce the alteration of sncRNA profiles in sperm, especially for transfer RNA-derived small RNAs (tsRNAs) and ribosomal RNA-derived small RNAs (rsRNAs). Zygotic injection of 29-34 nt RNA fractions (predominantly tsRNAs and rsRNAs) from oxidative stress (OS) sperm could induce depressive-like and anxiety-like behaviors in male offspring. Moreover, zygotic injection with synthetic RNAs partially resembled OS sperm-induced depressive-like and anxiety-like behaviors in offspring. Male offspring maintained on a chow diet was found to develop impaired glucose tolerance and hyperactive hepatic gluconeogenesis, accompanied by the upregulation of hepatic gluconeogenic and lipolytic genes. Together, our results have shown that ROS-induced alteration of sncRNA profiles in sperm contributes to the alterations of behavioral and metabolic phenotypes of the offspring.