Our aim was to investigate occurrence of senescent cells directly in tendon tissue biopsies from patients with chronic shoulder tendinopathies, and to correlate senescence with Enhancer of zeste 2 (EZH2) expression, the functional subunit of the epigenetic master regulator polycomb repressive complex. Human proximal long head of biceps tendons from patients with different chronic shoulder pathologies (n = 22), and controls from patients with humerus fracture (n = 6) and pathology (n = 4), were histologically scored for degeneration and analyzed for gene and protein expression of tendon specific factors, senescence markers, and EZH2. Tissues were further exposed to senotherapeutic compounds and the USA Food and Drugs Administration-approved selective EZH2 inhibitor EPZ-6438 and their senescence-associated secretory phenotype (SASP) assessed.Aims
Methods
The most prevalent disorders of the shoulder are related to the
muscles of rotator cuff. In order to develop a mechanical method
for the evaluation of the rotator cuff muscles, we created a database
of isometric force generation by the rotator cuff muscles in normal
adult population. We hypothesised the existence of variations according
to age, gender and dominancy of limb. A total of 400 healthy adult volunteers were tested, classified
into groups of 50 men and women for each decade of life. Maximal
isometric force was measured at standardised positions for supraspinatus,
infraspinatus and subscapularis muscles in both shoulders in every
person. Torque of the force was calculated and normalised to lean body
mass. The profiles of mean torque-time curves for each age and gender
group were compared.Objectives
Methods