Capsaicin inhibits Jurkat T-cell activation by blocking calcium entry current I(CRAC)

Capacitative calcium entry (CCE) through stores-operated Ca2+ channels is an absolute requirement for normal activation of T lymphocytes. Organic blockers/inhibitors of the channel(s) that carry the inward Ca2+ current (I(CRAC)) responsible for CCE are few. Here we show that capsaicin, the pungent ingredient of hot chili pepper, blocks receptor-stimulated Ca2+ entry in Jurkat T cells. Indo-1 measurements of intracellular calcium show that capsaicin blocks CCE without affecting release of inositol-1,4,5-trisphosphate-sensitive internal Ca2+ stores with an IC50 of 32 microM. Block of Ca2+ entry by capsaicin is identical whether CCE is evoked by T-cell receptor (TCR) stimulation, heterologous muscarinic M1 receptor stimulation, or via thapsigargin depletion of internal Ca2+ stores. Patch-clamp experiments show that capsaicin rapidly and reversibly blocks I(CRAC) with an identical dose response as seen with indo-1 measurements. The major voltage-gated K+ channel in Jurkat cells, Kv1.3, is also blocked by capsaicin. Although Kv1.3 block may contribute to reducing CCE by changes in membrane potential, block of I(CRAC) is the primary mechanism by which capsaicin reduces CCE. Capsaicin analogs capsazepine and resiniferatoxin also produce inhibition of CCE via block of I(CRAC). Upon application of capsaicin to Jurkat cells in culture we observed an inhibition of interleukin-2 (IL-2) production in response to TCR stimulation. The dose dependence of capsaicin's reduction of IL-2 was comparable with its block of I(CRAC), thereby illustrating the functional relevance of capsaicin's block of lymphocyte CCE. Thus, capsaicin and its numerous analogs may have potential use as immunomodulatory drugs and should be further investigated in models of inflammation and T-cell activation.

[One hundred years of bone surgery in the Lyons Teaching Hospitals (1897-1997)]

Throughout the XIXth century and until 1945, bone surgery focused primarily on correcting deformities in children. The treatment of injury-related bone lesions in adults (compound fractures and dislocations) remained within the province of general surgeons until circa 1970. Lyons played a unique role in the XVIIIth and XIXth centuries, for three reasons. 1) The term "orthopedics" (which means "straight children", or "children to be made straight") was coined in 1743 by an 80-year-old inhabitant of the Saint Nizier parish in Lyons, Nicolas Andry or André, a former dean of the Paris School of Medicine. The term was adopted throughout the world. 2) The first French orthopedic surgeon was Gabriel Pravaz, who was from the Pont-de-Beauvoisin neighborhood of Lyons. He treated "children to be made upright" in his orthopedic and pneumatic institute located quai des Etroits, and was the first to successfully reduce congenitally dislocated hips (before 1850). 3) In 1987, the most famous bone surgeon was Ollier, who brilliantly applied the method developed by Claude Bernard to the experimental study of the role of the periosteum. He observed that new bone was laid down after "subperiosteal resection" of infected bone or joint tissue. His technique allowed to reduce dramatically the number of limb amputations for infection. In 1897, in addition to Ollier (who died in 1900), many other outstanding surgeons from Lyons demonstrated an interest in bone surgery. Around 1897. Jaboulay (known as a vascular and transplantation surgeon) successfully performed amputations through the middle of the pelvis. Also during this period, Gangolphe used osteotomies to correct limb deformities, and also performed bone grafts. Between 1897 and 1910, the radiologist E. Destot, who worked at the Hôtel-Dieu hospital in Lyons, published two books on the classification of fractures, "The wrist" and "The foot", both of which were promptly translated in English. The Lyons School at the Hôtel-Dieu that demonstrated its excellence in the XIXth century gave birth in the XXth century to a school of infantile bone surgery, headed by G. Nové-Josserand from 1894 to 1937 then by L Tavernier from 1937 to 1947. Tavernier was a sports enthusiast, and was proficient not only in pediatric surgery but also in the areas of meniscal lesions and bone tumors. He was succeeded by Guilleminet (1947-1962), then by Joseph Marion. Two teaching hospital departments of adult orthopedic surgery were created, one headed by Albert Trillat, who, together with H. Dejour and A. Mounier-Khun, was known throughout Europe as an outstanding sports injury surgeon, and the other by Jean Creyssel, who worked with G. de Mourgues and played a significant role in France in bringing trauma-related injuries (traditionally treated by general surgeons) into the field of orthopedic surgery. The first successful total hip arthroplasty procedures were done around 1966. Orthopedics and traumatology became a separate specialty in 1969, and in the wake of this change many departments focusing only or preferentially on one part of the body (e.g., the hand and upper limb, knee, or hip) were created. Over the last century, the Lyons Society for Surgery has played a key role in publishing discoveries in bone surgery and in disseminating knowledge in this field. Although societies for surgery of the hip, knee, spine, hand, foot, and so on now exist, meetings of the Lyons Society for Bone Surgery remain useful since new ideas and techniques sometimes stem from experience acquired in other fields. It is worthy of note that in other European countries traumatology is a specialty in itself, which includes visceral and bone traumatology. It can be anticipated that harmonizing the traumatology specialty in Germay and the orthopedic surgery and traumatology specialty in France may raise a number of problems.