P2Y12 receptor involved in the development of chronic nociceptive pain as a sensory information mediator.

Direct or indirect damage to the nervous system (such as inflammation or tumor invasion) can lead to dysfunction and pain. The generation of pain is mainly reflected in the activation of glial cells and the abnormal discharge of sensory neurons, which transmit stronger sensory information to the center. P2Y12 receptor plays important roles in physiological and pathophysiological processes including inflammation and pain. P2Y12 receptor involved in the occurrence of pain as a sensory information mediator, which enhances the activation of microglia and the synaptic plasticity of primary sensory neurons, and reaches the higher center through the ascending conduction pathway (mainly spinothalamic tract) to produce pain. While the application of P2Y12 receptor antagonists (PBS-0739, AR-C69931MX and MRS2359) have better antagonistic activity and produce analgesic pharmacological properties. Therefore, in this article, we discussed the role of the P2Y12 receptor in different chronic pains and its use as a pharmacological target for pain relief.

SARS-CoV-2: Operating room management strategies and recommendations.

Since the outbreak of SARS-CoV-2/COVID-19 in Wuhan, China in 2019, it has rapidly spread to the world, and the number of infections has gradually increased. The hospitalization rate of patients has also gradually increased, which poses a huge challenge to hospitals and medical staff for patients with SARS-CoV-2 requiring surgical treatment. Therefore, avoiding cross-infection in the operating room is an important protective work. The operating room is an important department of the hospital, scientific and reasonable management is particularly important. Therefore, we have put forward corresponding suggestions and strategies for preoperative preparation and evaluation of patients, intraoperative management, postoperative terminal management, and protection of medical staff, and hope that these measures can better prevent and control the infection of SARS-CoV-2 in the operating room.

P2X7 receptor in inflammation and pain.

Different studies have confirmed P2X7 receptor-mediated inflammatory mediators play a key role in the development of pain. P2X7 receptor activation can induce the development of pain by mediating the release of inflammatory mediators. In view of the fact that P2X7 receptor is expressed in the nervous system and immune system, it is closely related to the stability and maintenance of the nervous system function. ATP activates P2X7 receptor, opens non-selective cation channels, activates multiple intracellular signaling, releases multiple inflammatory cytokines, and induces pain. At present, the role of P2X7 receptor in inflammatory response and pain has been widely recognized and affirmed. Therefore, in this paper, we discussed the pathological mechanism of P2X7 receptor-mediated inflammation and pain, focused on the internal relationship between P2X7 receptor and pain. Moreover, we also described the effects of some antagonists on pain relief by inhibiting the activities of P2X7 receptor. Thus, targeting to inhibit activation of P2X7 receptor is expected to become another potential target for the relief of pain.

MAKO robotic assisted total hip replacement (THR) for patients with fused hips.

BACKGROUND: Previous articles about MAKO robotic-assisted total hip replacement (THR) were mainly in patients with comparatively normal anatomy. METHODS: From July 2020 to June 2021, we performed MAKO robotic-assisted THR in three hip-fused patients. We assessed the accuracy of prostheses implantation, collected clinical data, and discussed the value of this technique in this kind of patients. RESULT: All three patients achieved good leg length and prostheses position. A patient got femoral artery injury during the surgery. Moreover, she developed a thrombus. All three patients got acceptable Visual Analogue Scale scores and function recovery 6 months later. CONCLUSION: MAKO robotic-assisted THR achieved excellent prosthesis position in hip fused patients. More cases are needed to confirm this advantage. The function recovery was acceptable. Caution should be paid to protect the surrounding abnormal arteries, especially in a limited surgical field.

Restoration of cartilage defects using a superparamagnetic iron oxide-labeled adipose-derived mesenchymal stem cell and TGF-ß3-loaded bilayer PLGA construct.

Aim: We aimed to evaluate the capacity of the bilayer polylactic-co-glycolic acid (PLGA)/TGF-ß3/adipose-derived mesenchymal stem cell (ADSC) construct used to repair cartilage defects and the role of ADSCs in the repair process in vivo. Materials & methods: Defects were created surgically on the femoropatellar groove of knee joints in 64 rabbits. All the rabbits were randomly divided into four groups: defect group, PLGA group, PLGA/TGF-ß3 group and PLGA/TGF-ß3/ADSC group. In vivo MRI and Prussian blue staining were applied. Quantitative real-time PCR and western blot methods were used to analyze the gene and protein expression. Results & conclusion: The result showed that TGF-ß3 could effectively stimulate the expressions of aggrecan, collagen type II and SRY-related HMG box 9 (SOX9). The bilayer PLGA/TGF-ß3/ADSC construct showed a promising repair effect.

Dehydroepiandrosterone and age-related musculoskeletal diseases: Connections and therapeutic implications.

Musculoskeletal disorders related to ageing are one of the most common causes of mortality and morbidity among elderly individuals worldwide. The typical constitutive components of the musculoskeletal system, including bone, muscle, and joints, gradually undergo a process of tissue loss and degeneration as a result of life-long mechanical and biological stress, ultimately leading to the onset of a series of age-related musculoskeletal diseases, including osteoporosis (OP), sarcopenia, and osteoarthritis (OA). Dehydroepiandrosterone (DHEA), a precursor of androgen secreted mainly by the adrenal gland, has attracted much attention as a marker for senescence due to its unique age-related changes. This pre-hormone has been publicly regarded as an "antidote for ageing" because of its favourable effect against a wide range of age-related diseases, such as Alzheimer disease, cardiovascular diseases, immunosenescence and skin senescence, though its effect on age-related musculoskeletal diseases has been explored to a lesser extent. In the present review, we summarized the action of DHEA against OP, sarcopenia and OA. Extensive detailed descriptions of the pathogenesis of each of these musculoskeletal disorders are beyond the scope of this review; instead, we aim to highlight the association of changes in DHEA with the processes of OP, sarcopenia and OA. A special focus will also be placed on the overlapping pathogeneses among these three diseases, and the molecular mechanisms underlying the action of DHEA against these diseases are discussed or postulated.

Comparison between two rabbit models of posttraumatic osteoarthritis: A longitudinal tear in the medial meniscus and anterior cruciate ligament transection.

Animal osteoarthritis (OA) models have been developed to understand OA progression and evaluate new OA therapies. However, individual variations in joint lesions remain a critical problem in most current OA models. We established a novel rabbit model by creating a longitudinal tear in the medial meniscus body that was reproducible and similar to posttraumatic biomechanical disturbances in human OA. New Zealand rabbits underwent surgery and were assessed for 9 weeks. The rabbits were randomized into the sham control, medial meniscal tear (MMT), and anterior cruciate ligament transection (ACLT) groups. The animals were sacrificed at 4, 6, and 9 weeks posttreatment. The knee joints were harvested for histological and gene expression assessments. Both the MMT and ACLT procedures led to time-dependent degenerative changes in the femoral condyle cartilage. At each time point, the MMT group cartilage showed more severe degenerative changes than did the ACLT group cartilage. Consistently, inflammatory cytokine and catabolic gene expression were significantly higher, and anabolic gene expression was significantly lower in the MMT group than in the ACLT group. MMT treatment caused more severe structural damage to the cartilage and higher catabolic gene expression levels than the ACLT model at each time point. The MMT model may be highly beneficial in investigating posttraumatic OA (PTOA) development, especially PTOA from a meniscal injury. The MMT model replicated key features of human PTOA, including meniscal lesions, inflammatory responses, and the progression to osteoarthritic cartilage degeneration, thereby providing an exciting new avenue for translating promising treatments to clinical practice.

Platelet-Rich Plasma Versus Corticosteroid Injections in the Management of Elbow Epicondylitis and Plantar Fasciitis: An Updated Systematic Review and Meta-analysis.

BACKGROUND: Platelet-rich plasma (PRP), as a promising alternative to traditional corticosteroid (CS), is now increasingly used in the treatment of elbow epicondylitis (EE) and plantar fasciitis (PF). To date, however, the synthesis of information on the clinical efficacy of PRP versus CS is limited with divergent conclusions. PURPOSE: To compare the clinical efficacy of PRP and CS injections in reducing pain and improving function in EE and PF. STUDY DESIGN: Systematic review and meta-analysis. METHODS: Online databases were searched from inception to October 2018 for prospective studies evaluating PRP versus CS injections for EE or PF. Independent reviewers undertook searches, screening, and risk-of-bias appraisals. The primary outcomes of interest were pain and function in both the short term (1-3 months) and the long term (≥6 months). RESULTS: Twenty trials with 1268 participants were included. For EE, PRP provides a statistically and clinically meaningful long-term improvement in pain, with a very large effect size of -1.3 (95% CI, -1.9 to -0.7) when compared with CS, but the evidence level was low. For EE, there was moderate evidence that CS provides a statistically meaningful improvement in pain in the short term, with a medium effect size of 0.56 (95% CI, 0.08-1.03) as compared with PRP; this improvement might not be clinically significant. For PF, there was low evidence that PRP provides a statistically and clinically meaningful long-term improvement in function (American Orthopedic Foot & Ankle Society score), with a very large effect size of 1.94 (95% CI, 0.61-3.28). There were no significant differences between the groups in improvement in function in EE and pain and short-term function in PF, but the quality of the evidence was low. CONCLUSION: The use of PRP yields statistically and clinically better improvement in long-term pain than does CS in the treatment of EE. The use of PRP yields statistically and clinically better long-term functional improvement than that of CS in the treatment of PF.

Role of infrapatellar fat pad in pathological process of knee osteoarthritis: Future applications in treatment.

It has been found that obese people have a higher proportion in suffering from osteoarthritis (OA), not only in the weight-bearing joints like knee and hip joints, even in non-weight-bearing joints such as hand joints. One of the reasons is because the large amount of adipose tissue secretes some factors, which can promote the occurrence of arthritis. As an important structure of the knee joint, the infrapatellar fat pad (IPFP) is actually a piece of adipose tissue. The aim of this review is to offer a comprehensive view of the anatomy and physiological characteristics of IPFP and its relationship with the pathological process of OA, indicating the important function of IPFP in OA. At the same time, with the development of adipose derived stem cells in the treatment of OA, owing to its special advantages, the IPFP is becoming a kind of important, minimally invasive fat stem cell source, providing a new approach for the treatment of OA. We hope that this review will offer an overview of all published data regarding the IPFP and will indicate novel directions for future research.

[Double plating through different approaches for periprosthetic femoral fracture following total knee arthroplasty].

OBJECTIVE: To study clinical effects of double plating through different approaches for communicated and obvious osteoporosis periprosthetic femoral fracture following total knee arthroplasty(TKA). METHODS: From July 2010 to June 2017, 21 patients with periprosthetic femoral fracture following TKA were divided into two groups according to operative approach. Fifteen patients in medial and lateral double approaches group, including 5 males and 10 females aged from 63 to 79 years old with an average of (67.2±5.9) years old; 11 patients were type 33-A2 and 4 patients were type 33-A3 according to AO-OTA classification; 12 patients injured by falling down and 3 patients by traffic accident; treated with double plating. Six patients in medial parapatellar approach group, including 3 males and 3 females, aged from 61 to 74 years old with an average of (64.6±6.0) years old; 3 patients were type 33-A2 and 3 patients were type 33-A3 according to AO-OTA classification; 5 patients injured by falling down and 1 patient by traffic accident; treated with double plating. Operative time, blood loss, postoperative drainage, fracture healing time were compared between two groups; HSS score and radiology at 3 and 12 months were compared between two groups. RESULTS: All patients were followed up, and the follow-up time of bilateral approaches group ranged from 12 to 18 months with an average of (14.2±2.6 ) months, while the follow-up time of single approach group ranged from 12 to 16 months with an average of (12.6±2.5) months, and there was no statistical difference between two groups. The operative time and postoperative drainage in bilateral approaches group were (107.2±10.4) min and (213.9±30.4) ml, while in sigle approach group was (95.4±12.8) min and (256.8±34.2) ml, and the differences were significant(P<0.05). There were no significant difference in blood loss and fracture healing time(P>0.05). HHS score at 3 and 12 months after operation in bilateral approach were 82.9±5.7 and 84.8±7.1, while in single approach group were 83.6±6.1 and 86.3±6.8; there was no statistical difference in HSS score between two groups(P>0.05). According to HSS score at 12 months after operation, 2 cases got excellent results and 13 good in bilateral approaches group; 1 case got excellent result and 4 good and 1 moderate in single approach group; but there was no statistical difference between two groups (χ²=2.625, P=0.105). There wase no significant differences in complications between bilateral approaches group(2 cases) and single approach group (1 case)(P>0.05). CONCLUSIONS: Double plating technique for communicated and obvious osteoporosis periprosthetic femoral fracture following TKA could obtain good function of knee joint. The medial parapatellar approach has shorter operative time, while the bilateral approaches had less drainage.

Efficacy and Safety of Tranexamic Acid in Intertrochanteric Fractures: A Single-Blind Randomized Controlled Trial.

OBJECTIVE: To investigate the efficacy and safety of tranexamic acid (TXA) in the reduction of bleeding and the need for transfusion in elderly intertrochanteric fracture patients. METHODS: A total of 100 patients with intertrochanteric fractures undergoing surgery were enrolled and randomly allocated to the TXA group in which patients (75.10 ± 8.27 years old) were treated with 1 g of TXA, or the control group (77.82 ± 6.42 years old) treated with a placebo. Surgery was performed by two senior orthopaedic surgeons from two institutions. The proximal femoral nail antirotation (PFNA) was conducted using the standard procedure. Three outcome measures, including blood loss, transfusion, and complications, were recorded. Blood loss and transfusion were investigated to assess TXA's effectiveness, while complications were investigated to assess TXA's safety. Statistical indicators for blood loss included total, intraoperative, postoperative, and hidden blood loss volumes, calculated by hemoglobin levels, hematocrit levels, and drainage volume. The number and amount of blood transfusions were recorded. Complications associated with surgery, including deep vein thrombosis, pulmonary embolism, wound hematoma, wound infection, cardiovascular and cerebrovascular accidents, and respiratory infections, were also recorded. RESULTS: All patients were followed up for 1 month after surgery. There were no significant differences in demographic and clinical characteristics between the two groups. The TXA group suffered significantly less total blood loss (563.37 ± 197.51 vs 819.25 ± 273.96 mL, 95% CI: -349.49 to -162.27, P < 0.01), intraoperative blood loss (140.3 ± 80.64 vs 230.5 ± 130.56 mL, 95% CI -132.74 to -47.66, P < 0.01), and hidden blood loss (410.42 ± 178.23 vs 571.19 ± 218.13 mL, 95% CI: -238.85 to -82.69, P < 0.01) than the control group. However, postoperative total blood loss was not significantly different (97.5 ± 20.93 vs 94.7 ± 35.78 mL; P = 0.63). A total of 5 patients from the TXA group and 27 from the control group received packed RBC for postoperative transfusion, but the mean number of transfusion units was not significantly different between groups. Complications including deep vein thrombosis, pulmonary embolism, myocardial infarction, ischemic cerebral infarction, hematoma, and infection were observed in both groups, but no significant differences were found. CONCLUSIONS: In intertrochanteric fracture surgery performed using PFNA, intravenous administration of TXA significantly reduced the risk of intraoperative, total and hidden blood loss, in addition to the need for allogeneic transfusion, without increasing the rate of complications.

Tricetin Protects Rat Chondrocytes against IL-1ß-Induced Inflammation and Apoptosis.

Tricetin is a well-studied flavonoid with a wide range of pharmacological activities in cancer and inflammation. However, the ability of tricetin to ameliorate the inflammation that occurs in osteoarthritis (OA) has not been determined. This study explored the effects of tricetin on interleukin- (IL-) 1ß-induced rat chondrocytes. Chondrocytes harvested from rat cartilage were incubated in vitro with tricetin in the presence of IL-1ß. The expression of matrix metalloproteinase- (MMP-) 1, MMP-3, MMP-13, nitric oxide (NO), prostaglandin E2 (PGE2), Bax, and Bcl-2 was evaluated by real-time-PCR, ELISA, Griess reaction, and western blotting. Caspase-3 activity in chondrocytes was determined using a caspase-3 activity assay and MAPK pathway activity by western blotting. Tricetin decreased the expression of MMP-1, MMP-3, and MMP-13 at both the gene and protein level in IL-1ß-induced rat chondrocytes. It also inhibited IL-1ß-induced NO and PGE2 production, by modulating inducible NO synthase and cyclooxygenase 2 gene expression. An antiapoptotic role of tricetin involving the Bax/Bcl-2/caspase-3 pathway was also determined. The chondroprotective effect of tricetin was shown to be partly related to the suppression of the MAPK signaling pathway. The results of this study demonstrate the chondroprotective role of tricetin, based on its anticatabolic, anti-inflammatory, and antiapoptotic effects in chondrocytes. The therapeutic potential of tricetin in OA patients should be explored in future studies.

Potential of dehydroepiandrosterone in modulating osteoarthritis-related pain.

Osteoarthritis (OA) is the most common form of degenerative arthropathy, and the primary symptom is chronic joint pain. Dehydroepiandrosterone (DHEA) exerts a chondroprotective effect against OA and has been reported to have potent structure-modifying effects on osteoarthritic cartilage, thereby attenuating disease progression. However, the ability of DHEA to modulate OA-related pain has not yet been verified. Recent evidence suggests that there may be a link between the pharmacological effects of DHEA and pain generation. For example, DHEA synthesized in the adrenal gland interferes directly with nerve growth factor (NGF) receptors, a major biochemical contributor to peripheral hypersensitivity. Similarly, endogenous DHEA produced in the spinal cord exerts a regulatory effect on nociception in neuropathic rats. In this short review, we discuss recent studies concerning crucial signalling cascades and molecular mechanisms involved in pain generation as well as the potential link between DHEA activity and nociception. Particular attention is given to the putative molecular mechanisms underlying the favourable efficacy of DHEA against pain generation. Elucidating the molecular mechanisms of DHEA against osteoarthritic pain may pave the way for the discovery and development of novel anti-OA drugs, as effective drugs for OA treatment are not currently available.

Follistatin-like protein 1 (FSTL1) promotes chondrocyte expression of matrix metalloproteinase and inflammatory factors via the NF-κB pathway.

BACKGROUND: The expression of follistatin-like protein 1 (FSTL1) is closely associated with diseases of the musculoskeletal system. However, despite being a well characterized inflammatory mediator, the effects of FSTL1 on chondrocytes are not completely understood. In this study, we investigated the effects of FSTL1 on the expression of inflammatory and catabolic factors in rat chondrocytes. METHODS: Rat chondrocytes were treated directly with various concentrations of FSTL1 in vitro. The levels of matrix metalloproteinases (MMPs), inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, interleukin (IL)-1ß, tumour necrosis factor (TNF)-α and IL-6 were measured by polymerase chain reaction, ELISA and Western blotting. In addition, activation of the nuclear factor kappa B (NF-κB) pathway was explored to identify potential regulatory mechanisms. RESULTS: Follistatin-like protein 1 directly increased the expression of MMP-1, MMP-13, iNOS, COX-2, IL-1ß, TNF-α and IL-6 at both gene and protein level in a dose-dependent manner. Activation of NF- κB and phosphorylation of p65 were also promoted by FSTL1 stimulation. CONCLUSIONS: Follistatin-like protein 1 exerts pro-inflammatory and catabolic effects on cultured chondrocytes via activation of the NF-κB signalling pathway. FSTL1 may therefore be a target in the treatment of OA.

Paeoniflorin inhibits IL-1ß-induced MMP secretion via the NF-κB pathway in chondrocytes.

Paeoniflorin serves important cellular roles, exerting anti-cancer, anti-inflammatory and anti-pulmonary fibrosis effects and possesses immune-modulatory properties. However, the exact role of paeoniflorin in the pathogenesis of osteoarthritis (OA) remains unclear. The aim of the present study was to investigate the effects of paeoniflorin on articular surfaces in vitro. Rat chondrocytes were cultured in vitro and an MTT assay was performed to assess chondrocyte survival. Following treatment with interleukin (IL)-1ß and paeoniflorin, the production of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases-1 (TIMP-1) was examined using reverse transcription-quantitative polymerase chain reaction and western blotting. The interleukin (IL)-1ß-induced nuclear factor (NF)-κB pathway activation was also investigated. The results demonstrated that paeoniflorin was able to downregulate the expression of MMP and increase the expression of TIMP-1ntmRNA and protein in IL-1ß-induced rat chondrocytes. Furthermore, treating chondrocytes with paeoniflorin blocked the activation of NF-κB. These results suggest that paeoniflorin may serve am anti-catabolic role in the progression of OA and may be an effective preventative treatment for OA.

Dehydroepiandrosterone and Experimental Osteoarthritis.

Despite an increased understanding of the pathogenesis of osteoarthritis (OA) and the availability of a number of drugs designed to ameliorate its symptoms, a successful disease-modifying therapy remains elusive. Recent lines of evidence suggest that dehydroepiandrosterone (DHEA), a 19-carbon steroid hormone classified as an adrenal androgen, exerts a chondroprotective effect in OA patients, and it has been proven to be an effective DMOAD candidate that slows OA progression. However, the exact mechanisms underlying its anti-OA effect is largely unknown. This review summarizes emerging observations from studies of cell biology, preclinical animal studies, and preliminary clinical trials and describes the findings of investigations on this topic to develop an initial blueprint of the mechanisms by which DHEA slows OA progression. Presently, studies on DMOADs are increasing in importance but have met limited success. Encouragingly, the current data on DHEA are promising and may prove that DHEA-based treatment is efficacious for preventing and slowing human OA progression.

Dehydroepiandrosterone: Molecular mechanisms and therapeutic implications in osteoarthritis.

Dehydroepiandrosterone (DHEA), a 19-carbon steroid hormone primarily synthesized in the adrenal gland, exerts a chondroprotective effect against osteoarthritis (OA) and has been considered an effective candidate of disease-modifying OA drugs (DMOADs) that slow disease progression. We and others previously demonstrated that DHEA exerted a beneficial effect on osteoarthritic cartilage by positively modulating the balance between anabolic and catabolic factors (e.g., MMPs/TIMP-1, ADAMTS/TIMP-3 and cysteine proteinases/cystatin C), inhibiting catabolic signaling pathways (e.g., Wnt/ß-catenin), and suppressing proinflammatory cytokines-mediated low-grade synovial inflammation (e.g., IL-1ß). However, the full picture of the pharmacological molecular mechanism(s) underlying the activity of DHEA against OA is still incomplete, and a comprehensive and up-to-date review article in this field is unavailable. In this review, recent findings (apart from the well documented pathogenesis of OA) regarding disease-related mechanisms involving low grade synovial inflammation, cartilage matrix stiffness, chondrocyte autophagy and the roles of a variety of catabolic cellular signaling pathways are discussed. Moreover, the possible relationship between these disease-related mechanisms and DHEA action is discussed. Emerging evidence from in vivo and in vitro studies were scrutinized and are concisely presented to demonstrate the investigational and putative mechanisms underlying the anti-OA potential of DHEA.

Paeoniflorin inhibits IL-1ß-induced chondrocyte apoptosis by regulating the Bax/Bcl-2/caspase-3 signaling pathway.

Apoptosis serves a pivotal role in the pathogenesis of osteoarthritis (OA). Increasing evidence has demonstrated that paeoniflorin exerts key properties (including anticancer, anti-inflammation and neuroprotective) for clinical applications. However, the precise role of paeoniflorin in articular cartilage apoptosis remains unknown. The present study explored the effects and potential molecular mechanism of paeoniflorin on rat chondrocyte apoptosis. Rat articular chondrocytes were cultured in monolayers. The lactate dehydrogenase (LDH) release rate of cells was determined by an LDH release assay. Annexin V-fluorescein isothiocyanate and propidium iodide staining were performed to detect early and advanced apoptotic cells by flow cytometry. The activity of caspase-3 in chondrocytes was determined using a caspase-3 activity assay. The expression of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) was examined by reverse transcription­quantitative polymerase chain and western blotting. The present study also examined the protein kinase B (Akt) signaling pathway by western blotting. Treatment with 25 or 50 µM paeoniflorin markedly decreased the release of LDH and the ratio of apoptotic cells in interleukin (IL)-1ß-induced rat chondrocytes. Paeoniflorin treatment decreased the mRNA and protein levels of Bax, and increased the level of Bcl-2. Paeoniflorin also reduced the activity of caspase-3 in chondrocytes. Furthermore, paeoniflorin was determined to regulate the Akt signaling pathway by increasing Akt phosphorylation. Therefore, paeoniflorin may exert its protective effect by inhibiting apoptosis in IL-1ß-induced rat chondrocytes and thus, may be an effective agent in the prevention and treatment of OA.

Effect of parenteral glutamine supplementation combined with enteral nutrition on Hsp90 expression and Peyer's patch apoptosis in severely burned rats.

OBJECTIVES: The aim of this study was to investigate the effects of parenteral glutamine (GLN) supplementation combined with enteral nutrition (EN) on heat shock protein (Hsp) 90 expression and Peyer's patch (PP) apoptosis in severely burned rats. METHODS: Male Sprague-Dawley (SD) rats were randomly assigned to four groups: Sham burn + EN + GLN-free amino acid (AA; n = 10), sham burn + EN + GLN (n = 10), burn + EN + AA (n = 10), and burn + EN + GLN (n = 10). Two hours after a 30% total body surface area (TBSA), full-thickness scald burn injury on the back, burned rats in two of the experimental groups (burn + EN + AA and burn + EN + GLN groups) were fed with a conventional EN solution by oral gavage for 7 d. Simultaneously, rats in the burn + EN + GLN group were given 0.35 g GLN/kg body weight/d once via a tail vein injection for 7 d and rats in the burn + EN + AA group were administered isocaloric/isonitrogenous GLN-free amino acid solution (Tyrosine) for comparison. Rats in two sham burn control groups (sham burn + EN + AA and sham burn + EN + GLN groups) were treated in the same manner except for the burn injury. All rats in the four groups were given 175 kcal/kg body wt/d. There was isonitrogenous, isovolumic, and isocaloric intake among the four groups. At the end of the seventh day after completion of the nutritional program, all rats were anesthetized and samples were collected for further analysis. PP apoptosis was measured by terminal deoxyuridine nick-end labeling (TUNEL). The expression of Hsp90 in PPs was analyzed by western blotting. Caspase-3 activity of PPs was also assessed. Levels of proinflammatory cytokines of gut tissues were evaluated by enzyme-linked immunosorbent assay (ELISA). The intestinal immunoglobulin A (IgA) content was also determined by ELISA. RESULTS: The results revealed that intestinal IgA content in rats of the burn + EN + GLN group were significantly increased compared with those in the burn + EN + AA group (P < 0.05). The expression of Hsp90 of PPs in rats in the burn + EN + GLN group was significantly upregulated compared with those in the burn + EN + AA group (P < 0.05). On the other hand, levels of proinflammatory cytokines of gut tissues, caspase-3 activity, and the number of TUNEL-stained cells of PPs in rats of the burn + EN + GLN group were markedly decreased compared with those of the burn + EN + AA group (P < 0.05). CONCLUSIONS: The results of this study show that parenteral glutamine supplementation combined with EN may upregulate the expression of Hsp90, reduce caspase-3 activity, lessen the release of proinflammatory cytokines, attenuate PP apoptosis, and improve intestinal IgA response in burned rats. Clinically, therapeutic efforts to improve intestinal immunity may contribute to a favorable outcome in severely burned patients.

Rosmarinic acid down-regulates NO and PGE2 expression via MAPK pathway in rat chondrocytes.

Rosmarinic acid (RosA) is a water-soluble polyphenol, which can be isolated from many herbs such as orthosiphon diffuses and rosmarinus officinalis. Previous studies have shown that RosA possesses various biological properties. In this study, we investigate the anti-osteoarthritic effects of RosA in rat articular chondrocytes. Chondrocytes were pre-treated with RosA, followed by the stimulation of IL-1ß. Real-time PCR and Western blot were performed to detect the expression of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-13. Nitric oxide and PGE2 production were measured by Griess reagent and enzyme-linked immunosorbent assay (ELISA). The expression of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) was also investigated by Western blot analysis. We found that RosA down-regulated the MMPs expression as well as nitric oxide and PGE2 production in IL-1ß-induced chondrocytes. In addition, RosA inhibited p38 and JNK phosphorylation as well as p65 translocation. The results suggest that RosA may be considered a possible agent in the treatment of OA.