Publications by authors named "L B Belardin"

Introduction: The epididymis creates an optimal acidic luminal environment for sperm maturation and storage. In epididymal principal cells (PCs), proton secretion is activated by the accumulation of the sodium-proton exchanger type 3, NHE3 (SLC9A3), in apical stereocilia. PCs also secrete ATP, which is hydrolyzed into adenosine by ectonucleotidases.

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Article Synopsis
  • * In spontaneously hypertensive rats (SHRs), researchers found lower sperm concentration, motility, and higher acrosome damage, with SHRs showing elevated blood pressure across different ages.
  • * Treatment with prazosin, which blocks α1-adrenergic receptors, improved sperm concentration and motility in hypertensive rats, but did not help with acrosome damage, highlighting the impact of hypertension on sperm quality.
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Study Question: Is it possible to remove sperm with damaged DNA from a semen sample?

Summary Answer: By using immunomagnetic cell sorting that targets the sperm head-bound epididymal sperm-binding protein 1 (ELSPBP1), it was possible to produce an ELSPBP1(-) sperm fraction characterized by consistently lower levels of sperm DNA fragmentation (SDF).

What Is Known Already: In bovines, ELSPBP1 is bound to dead spermatozoa. Human ejaculates with high SDF have increased detected levels of sperm ELSPBP1 when compared to ejaculates with low native SDF.

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Purinergic receptors are ubiquitously expressed throughout the body and they participate in the autocrine and paracrine regulation of cell function during normal physiological and pathophysiological conditions. Extracellular nucleotides activate several types of plasma membrane purinergic receptors that form three distinct families: P1 receptors are activated by adenosine, P2X receptors are activated by ATP, and P2Y receptors are activated by nucleotides including ATP, ADP, UTP, UDP, and UDP-glucose. These specific pharmacological fingerprints and the distinct intracellular signaling pathways they trigger govern a large variety of cellular responses in an organ-specific manner.

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Background: Vasectomy causes spermatozoa accumulation in the epididymis, which may cause epididymitis. Inflammation is triggered by alert molecules released following tissue stress or injury. These include uracil-diphosphate glucose (UDP)-glucose, which activates the pro-inflammatory P2Y14 receptor (P2Y14), and induces immune cell recruitment.

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