thymosin and Pain

Prothymosin alpha (ProTα)-mimetic hexapeptide (amino acid: NEVDQE, P6Q) inhibits cerebral or retinal ischemia-induced behavioral, electrophysiological and histological damage. P6Q also abolishes cerebral hemorrhage induced by ischemia with tissue plasminogen activator (tPA). In the present study we examined the beneficial effects of P6Q on other post-stroke prognostic psychology-related symptoms, which obstruct the motivation toward physical therapy. Intravenous (i.v.) administration with tPA (10 mg/kg) at 6 h after photochemically induced thrombosis (PIT) in mice resulted in bilateral central post-stroke pain in thermal and mechanical nociception tests and loss of social activity in the nest building test, both of which were significantly blocked by P6Q (30 mg/kg, i.v.) given at 5 h after PIT. P6Q (30 mg/kg, i.v.) also improved the memory-learning deficit in the step-through test and depression-like behavior in the tail suspension test when it was given 1 day after bilateral common carotid arteries occlusion (BCCAO) in mice. Thus, these studies suggest that P6Q could be a promising candidate to prevent negative prognostic psychological symptoms following focal and global ischemia.

Topics: Animals; Brain Ischemia; Depression; Learning; Male; Memory Disorders; Mice; Mice, Inbred C57BL; Neuroprotective Agents; Pain; Peptide Fragments; Protein Precursors; Stroke; Thymosin; Tissue Plasminogen Activator

Our aim was to investigate the influence of thymic polypeptides on pain sensitivity and to analyze a possible role of the opioid system in the implementation of the analgesia caused by immobilization stress.. The study was performed on male Wistar rats at the Moscow state University named after M. V. Lomonosov. We studied effects of thymus peptides: thymuline (0.15 mg/kg), fraction 5 thymosin (0.25 microgram/kg) and cattle thymus extracted product (CTEP) (0.5 mg/kg) on pain sensitivity in rats using test "tail flick" without stress, with acute (3 h) and sub acute (12 h) immobilization stress. The comparison groups were animals treated with saline and spleen polypeptides.. It is shown that preparations of thymus increase the threshold of pain sensitivity in the intact animals. Immobilization stress duration 3 and 12 h in thymus peptides treated rats caused a less pronounced increase in pain threshold than in the control groups (immobilization stress 3 h: CTEP--p = 0.025, thymuline--p = 0.022, fraction 5 thymosin--p = 0.033; immobilization stress 12 h: CTEP--p = 0.034, thymuline--p = 0.027, fraction 5 thymosin--p = 0.036). The opioid receptor blocker naloxone (1 mg/kg) did not completely block the stress-induced analgesia, indicating the presence of both opioid and non -opioid components in this state. In thymus peptides treated rats, opioid component was less pronounced than in the control groups (CTEP--p = 0.031, thymuline--p = 0.026, fraction 5 thymosin--p = 0.029).. Pre-activation of the opioid system by the thymus polypeptides leads to an increase in the share of non-opioid component of the stress-induced analgesia and prevents the depletion of the opioid system in immobilization stress.

Topics: Analgesia; Animals; Cattle; Male; Models, Animal; Naloxone; Narcotic Antagonists; Pain; Pain Management; Rats; Rats, Wistar; Receptors, Opioid; Restraint, Physical; Thymic Factor, Circulating; Thymosin; Thymus Extracts; Thymus Gland

Pressure ulcers occur in up to 14% of acute hospitalizations. They cause pain, decreased quality of life, increased morbidity, and prolonged hospitalizations. Treatment includes pain control, nutritional support, relieving pressure, removing devitalized tissue, and by using dressings and medications, providing an environment in which healing can occur. Even with optimal treatment, pressure ulcers may take months to heal. Thymosin beta4 is being investigated as a treatment for pressure ulcers. Thymosin beta4 has wound healing and anti-inflammatory properties. It is thought to exert its therapeutic effect through promotion of keratinocyte and endothelial cell migration, increased collagen deposition, and stimulation of angiogenesis. A study in a rat full-thickness wound model showed that treatment with thymosin beta4 increased collagen deposition and angiogenesis and stimulated keratinocyte migration and reepithelialization. If thymosin beta4 decreases healing time, this would represent a significant advance in the treatment of pressure ulcers.

Topics: Humans; Pain; Pressure Ulcer; Quality of Life; Thymosin