Aim Butyrate is a major gut microbiota‐derived metabolite. Reduced butyrate‐producing bacteria has been reported in the spontaneously hypertensive rat (SHR), a model of hypertension characterized by dysfunctional autonomic nervous system and gut dysbiosis. Here, we demonstrate a potential mechanism for butyrate in blood pressure regulation. Methods High‐performance liquid chromatography and liquid chromatography‐mass spectrometry were performed to measure butyrate levels in feces and serum. Ussing chamber determined butyrate transport in colon ex vivo. Real‐time PCR and immunohistochemistry evaluated expression of butyrate transporter, Slc5a8, in the colon. Mean arterial blood pressure was measured in catheterized anesthetized rats before and after a single butyrate intracerebroventricular injection. Activity of cardioregulatory brain regions was determined by functional magnetic resonance imaging to derive neural effects of butyrate. Results In the SHR, we demonstrated elevated butyrate levels in cecal content, but diminished butyrate levels in circulation, possibly due to reduced expression of Slc5a8 transporter in the colon. In addition, we observed lower expression levels of butyrate‐sensing receptors in the hypothalamus of SHR, likely leading to the reduced effects of centrally administered butyrate on blood pressure in the SHR. Functional magnetic resonance imaging revealed reduced activation of cardioregulatory brain regions following central administration of butyrate in the SHR compared to control. Conclusion We demonstrated a reduced availability of serum butyrate in the SHR, possibly due to diminished colonic absorption. Reduced expression of butyrate‐sensing receptors in the SHR hypothalamus may explain the reduced central responsiveness to butyrate, indicating microbial butyrate may play a role in blood pressure regulation.

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2020). Marker-free carotenoid-enriched rice generated through targeted gene insertion using CRISPR-Cas9. Nat. Commun. 11, 1178.

Limited information is available regarding male reproductive physiology in West Indian manatees (Trichechus manatus). Currently, only basic ultrastructural and morphometric descriptions of the spermatozoon exist; however, there are no reports evaluating any seminal characteristics in this species. Therefore, the aim of the study was to fill current gaps in knowledge regarding semen parameters in West Indian manatees by collecting and characterizing multiple ejaculate samples from a single, adult West Indian manatee. Samples were analyzed for the following semen parameters: volume, agglutination, pH, osmolality, viscosity, concentration, total sperm number, motility and kinematic parameters, morphology, plasma membrane integrity, acrosome integrity, chromatin maturation, and chromatin condensation. All macroscopic semen parameters varied to some extent between samples. Total and progressive motility was high for ejaculates 2 to 5, exceeding 97 and 89%, respectively; however, these parameters decreased dramatically throughout ejaculates 6 and 7. Across all samples, curvilinear velocity, straight-line velocity, and average pathway velocity represented the largest significant differences (p < 0.001) between each of the progression velocity subgroups (rapid, medium, slow). Sperm characteristics, including acrosome integrity (79.8%), chromatin condensation (93.1%), and chromatin maturation (99.5%) were very high; however, high numbers of morphologically abnormal sperm were present (52.9%) and plasma membrane integrity was low (45.1%). These results are the first of their kind for this species and suggest high semen quality, based on multiple ejaculates, in this male West Indian manatee.