Combined effect of substance P and curcumin on cutaneous wound healing in diabetic rats.

BACKGROUND: Our earlier studies demonstrated that topically applied substance P (SP) or curcumin on excision skin wound accelerated the wound healing in streptozotocin-induced diabetic rats. In the present study, we aimed to evaluate the wound healing potential of combination of SP and curcumin in diabetic rats. MATERIALS AND METHODS: Open cutaneous excision wound was created on the back of each of the 60 diabetic rats. Wound-inflicted rats were equally divided into three groups namely, control, gel treated, and SP + curcumin treated. Normal saline, pluronic gel, and SP (0.5 × 10-6M) + curcumin (0.15%) were topically applied once daily for 19 d to these control, gel-treated, and SP + curcumin groups, respectively. RESULTS: SP + curcumin combination significantly accelerated wound closure and decreased messenger RNA expressions of tumor necrosis factor-alpha, interleukin-1beta, and matrix metalloproteinase-9, whereas the combination markedly increased the expressions of interleukin-10, vascular endothelial growth factor, transforming growth factor-beta1, hypoxia-inducible factor 1-alpha, stromal cell-derived factors-1alpha, heme oxygenase-1 and endothelial nitric oxide synthase, and activities of superoxide dismutase, catalase, and glutathione peroxidase in granulation-healing tissue, compared with control and gel-treated groups. In combination group, granulation tissue was better, as was evidenced by improved fibroblast proliferation, collagen deposition, microvessel density, growth-associated protein 43-positive nerve fibers, and thick regenerated epithelial layer. CONCLUSIONS: The combination of SP and curcumin accelerated wound healing in diabetic rats and both the drugs were compatible at the doses used in this study.

Effect of ursolic acid in attenuating chronic constriction injury-induced neuropathic pain in rats.

Ursolic acid (UA; 3b-hydroxy-12-urs-12-en-28-oic acid), a natural pentacyclic triterpenoid carboxylic acid, has been known to possess potent anti-inflammatory, antioxidant, and antinociceptive effects in various animal models. Therefore, this study was designed to investigate the antihyperalgesic, anti-inflammatory, and antioxidant effects of UA at 5, 10, and 20 mg/kg of doses via per os (p.o.) route for 14 days in chronic constriction injury (CCI)-induced neuropathic pain in rats. Pain behavior in rats was evaluated before and after UA administration via mechanical and heat hyperalgesia. CCI caused significant increase in levels of pro-inflammatory cytokines and oxido-nitrosative stress. In addition, significant increase in myeloperoxidase, malondialdehyde, protein carbonyl, nitric oxide (NO), and total oxidant status (TOS) levels in sciatic nerve and spinal cord concomitant with mechanical and heat hyperalgesia is also noted for CCI-induced neuropathic pain. Administration of UA significantly reduced the increased levels of pro-inflammatory cytokines and TOS. Further, reduced glutathione is also restored by UA. UA also showed in vitro NO and superoxide radical scavenging activity. UA has a potential in attenuating neuropathic pain behavior in CCI model which may possibly be attributed to its anti-inflammatory and antioxidant properties.

Effect of atorvastatin, a HMG-CoA reductase inhibitor in monosodium iodoacetate-induced osteoarthritic pain: implication for osteoarthritis therapy.

BACKGROUND: Oxidative stress is one of the main causes of pain and cartilage degradation in osteoarthritis. This study on atorvastatin, a HMG-CoA reductase inhibitor used in the treatment of hypercholesterolemia and prevention of coronary heart disease aimed to investigate its effect on hyperalgesia and cartilage damage in monosodium iodoacetate (MIA)-induced osteoarthritis model in rats. METHODS: Osteoarthritis was induced by a single intra-articular injection of 3mg MIA. After daily administration of atorvastatin (3, 10 and 30 mg/kg) for 20 days by oral gavage, pain was assessed on days 0, 1, 3, 7, 14 and 21. Histopathology of ipsilateral knee joint; oxidative markers and antioxidants in plasma were assessed on day 21. RESULTS: Atorvastatin attenuated hyperalgesia. The increased level of lipid peroxidation, superoxide, protein carbonyl; decreased activity of catalase, glutathione-S-transferase, reduced glutathione and total thiol levels in MIA rats were restored to the normal levels, however, superoxide dismutase and nitric oxide levels remained unaltered by atorvastatin. Further, atorvastatin reduced the MIA-induced histopathological alteration in the knee joint. CONCLUSION: Our study demonstrated that atorvastatin attenuates MIA-induced osteoarthritic pain and protect cartilage degradation through inhibition of oxidative stress suggesting its importance in osteoarthritic pain management.

Topical application of substance P promotes wound healing in streptozotocin-induced diabetic rats.

Substance P (SP) is known to stimulate angiogenesis, fibroblasts proliferation and expressions of cytokines and growth factors involved in wound healing. However, SP level reduces in dermis in diabetics and, hence, it was hypothesized that exogenously applied SP could be helpful in improving wound healing in diabetic rats. Excision skin wound was created on the back of diabetic rats and rats were divided into three groups i.e. (i) saline-, (ii) gel- and (iii) SP-treated. Normal saline, pluronic gel and SP (10(-6)M) in gel were topically applied once daily for 19days. SP treatment significantly increased the wound closure, levels of interleukin-10, and expressions of vascular endothelial growth factor, transforming growth factor-beta1, heme oxygenase-1 and endothelial nitric oxide synthase, whereas it significantly decreased the expression of tumor necrosis factor-alpha, interleukin-1beta and matrix metalloproteinases-9 in the granulation/healing tissue. The inflammatory cells were present for long time in normal saline-treated group. Histological evaluation revealed better extracellular matrix formation with marked fibroblast proliferation and collagen deposition in SP-treated group. Early epithelial layer formation, increased microvessel density and greater growth associated protein-43 positive nerve fibers were also evidenced in SP-treated group. In conclusion, SP treatment markedly accelerated cutaneous wound healing in diabetic rats.

Anti-inflammatory and chondroprotective effects of atorvastatin in a cartilage explant model of osteoarthritis.

OBJECTIVE: This study aimed to assess the chondroprotective potential of atorvastatin in rat's cartilage explant culture model of osteoarthritis, stimulated by interleukin-1ß (IL-1ß). MATERIALS AND METHODS: The cartilage explants were treated with 20 ng/ml IL-1ß alone or with 20 ng/ml IL-1ß + various concentration of atorvastatin (1, 3, or 10 µM dissolved in DMSO) and incubated at 37 °C for 24 h. Also, control (0.25% DMSO), stimulated (20 ng IL-1ß) and treatment (atorvastatin 10 µM) cartilage explants were incubated without and with 1400W (10 µM). After 24 h of incubation, TNF-α, PGE2, MMP-13, TIMP-1, NO, and superoxide anion formation (O2(-)) concomitant with glycosaminoglycans (GAGs) were estimated in the medium. RESULTS: Atorvastatin inhibited IL-1ß-induced GAGs release, TNF-α, MMP-13, and O2(-) with no effect on TIMP-1 and NO. In addition, the source of NO in normal and atorvastatin-treated cartilage was eNOS, while for IL-1ß-stimulated cartilage it was iNOS. The cartilage degradation was associated with the combined effects of increased NO and O2 (-) rather than only NO. CONCLUSION: The present study suggests that atorvastatin has the ability to protect cartilage degradation following IL-1ß-stimulated cartilage in in vitro OA model and supports additional therapeutic application of atorvastatin in OA.

Curcumin-induced angiogenesis hastens wound healing in diabetic rats.

BACKGROUND: Neovasculogenesis, vital for wound healing, gets compromised in diabetics patients, which consequently delayed wound healing. Previous studies have shown curcumin as both a stimulatory and an inhibitory agent in the neovasculogenesis process. So, present study was aimed to investigate the effects of curcumin on wound healing in diabetic rats and to explore the expressions of the various factors involved in neovasculogenesis. MATERIALS AND METHODS: Open excisional diabetic wound was created in sixty rats and divided into three groups viz. i) control, ii) pluronic gel-treated, and iii) curcumin-treated. The pluronic F-127 gel (25%) and curcumin (0.3%) in the pluronic gel were topically applied once daily for 19 d. The wound healing and neovasculogenesis among these groups were evaluated by gross appearance of wounds and microscopically by hematoxylin and eosin staining, immunohistochemistry for CD31, messenger RNA expressions of vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-ß1, hypoxia-inducible growth factor-1 alpha, stromal cell-derived growth factor-1 alpha, and heme oxygenase-1, and Western blotting studies of VEGF and TGF-ß1 in granulation and/or healing tissue on days 3, 7, 14, and 19. RESULTS: Curcumin application caused markedly fast wound closure with well-formed granulation tissue dominated by fibroblast proliferation, collagen deposition, and complete early regenerated epithelial layer. Immunohistochemistry for CD31 revealed well-formed blood vessels with increased microvessel density on days 3, 7, and 14 in the curcumin-treated group. Expressions of VEGF and TGF-ß1 on days 3, 7, and 14, hypoxia-inducible growth factor-1 alpha, stromal cell-derived growth factor-1 alpha, and heme oxygenase-1 on days 3 and 7 were increased in curcumin-treated diabetic rats, as compared with other groups. CONCLUSIONS: Curcumin enhanced the neovasculogenesis and accelerated the wound healing in diabetic rats by increased expressions of various factors.

Betulinic acid negates oxidative lung injury in surgical sepsis model.

BACKGROUND: Sepsis commonly progresses to acute lung injury and is associated with high morbidity and mortality. Septic acute lung injury is characterized by severe oxidative stress response, remained refractory to present therapies, and new therapies need to be developed to improve further clinical outcomes. We determined the effect of betulinic acid (BA) on oxidative lung injury in mice using cecal ligation and puncture (CLP) model. MATERIALS AND METHODS: Five groups of mice (six in each group) received three pretreatments at 24-h interval before surgery. Surgery was done 1 h after last dosing. Sham and CLP control group mice received vehicle. BA was administered to other three groups of mice at 3, 10, and 30 mg/kg dose. Lung and plasma samples were collected for analysis by sacrificing the mice at 18 h of surgery. RESULTS: Compared with sham, CLP significantly increased total protein, nitrite, malondialdehyde, isoprostane, superoxide, protein carbonyl, oxidative stress index, inducible nitric oxide synthase protein, and histopathologic changes and reduced the superoxide dismutase, catalase activity, and total thiol levels in lungs and plasma, which were restored by BA pretreatment. CONCLUSIONS: BA pretreatment decreased the levels of oxidants, increased the levels of antioxidants in lungs and plasma thereby reducing the oxidative lung injury in CLP mice. Additionally, BA was found to scavenge the superoxide and nitric oxide radical in vitro. Thus, BA is suggested to be effective in treatment of oxidative lung injury in sepsis.

Antioxidant and anti-inflammatory potential of curcumin accelerated the cutaneous wound healing in streptozotocin-induced diabetic rats.

Prolonged inflammation and increased oxidative stress impairs healing in diabetics and application of curcumin, a well known antioxidant and anti-inflammatory agent, could be an important strategy in improving impaired healing in diabetics. So, the present study was conducted to evaluate the cutaneous wound healing potential of topically applied curcumin in diabetic rats. Open excision skin wound was created in streptozotocin induced diabetic rats and wounded rats were divided into three groups; i) control, ii) gel-treated and iii) curcumin-treated. Pluronic F-127 gel (25%) and curcumin (0.3%) in pluronic gel were topically applied in the gel- and curcumin-treated groups, respectively, once daily for 19 days. Curcumin application increased the wound contraction and decreased the expressions of inflammatory cytokines/enzymes i.e. tumor necrosis factor-alpha, interleukin (IL)-1beta and matrix metalloproteinase-9. Curcumin also increased the levels of anti-inflammatory cytokine i.e. IL-10 and antioxidant enzymes i.e. superoxide dismutase, catalase and glutathione peroxidase. Histopathologically, the curcumin-treated wounds showed better granulation tissue dominated by marked fibroblast proliferation and collagen deposition, and wounds were covered by thick regenerated epithelial layer. These findings reveal that the anti-inflammatory and antioxidant potential of curcumin caused faster and better wound healing in diabetic rats and curcumin could be an additional novel therapeutic agent in the management of impaired wound healing in diabetics.

Atorvastatin attenuates neuropathic pain in rat neuropathy model by down-regulating oxidative damage at peripheral, spinal and supraspinal levels.

Atorvastatin is an HMG-CoA reductase inhibitor used in the treatment of hypercholesterolemia and prevention of coronary heart disease. Oxidative stress is considered to be one of the main causes of neuropathic pain after nerve injury. This study aimed to investigate the effect of atorvastatin on oxidative stress and hyperalgesia in chronic constriction injury (CCI) model of neuropathic pain. Pain behaviour in rats was evaluated before and after atorvastatin administration using mechanical and heat hyperalgesia. The markers for oxidative stress in sciatic nerve, spinal cord and pre-frontal cortex (PFC) area of brain were biochemically detected in vehicle and atorvastatin-treated neuropathic CCI rats. Atorvastatin attenuated hyperalgesia. We found a significant increase in malondialdehyde (MDA), nitric oxide (NO), superoxide anion (O2(-)) and protein carbonyl along with a reduction in catalase (CAT), reduced glutathione (GSH), total thiol (SH) and glutathione-S-transferase (GST) and; increase in superoxide dismutase (SOD) levels in the sciatic nerve, spinal cord and PFC of the CCI-induced neuropathic rats. Reduced levels of enzymatic and non enzymatic antioxidants were restored by atorvastatin. The levels of MDA, O2(-), and protein carbonyl in these tissues were significantly reduced in the atorvastatin-treated CCI rats compared to the untreated CCI rats. Our study demonstrated that atorvastatin attenuates neuropathic pain through inhibition of oxidative stress in sciatic nerve, spinal cord and brain suggesting antioxidants as potential drugs in neuropathic pain management. This study provides a new application of atorvastatin in treatment of neuropathic pain.

Topical pluronic F-127 gel application enhances cutaneous wound healing in rats.

Pluronic F-127 gel is used as vehicle for various topical applications. In the present study, effects of topical application of pluronic F-127 gel were evaluated in cutaneous wound healing in Wistar rats. Normal saline solution and pluronic F-127 gel (25%) were applied topically on open excision wounds for 14 days. Photography, determination of percentage wound contraction, and collection of granulation tissue were done on days 3, 7, 11 and 14 post-wounding. Topical application of gel (once daily) significantly increased the wound closure on days 11 and 14. The gel application increased the expressions of vascular endothelial growth factor (VEGF) and transforming growth factor-beta1 (TGF-ß1) on days 3 and 7. Histopathologically, more leukocyte infiltration followed by well formed granulation tissue with marked fibroblast proliferation was evident in the gel-treated group, as compared to the saline-treated control group. Immunohistochemistry of CD31 on day 7 revealed significant higher microvessel density in gel-treated wounds. Picrosirius staining demonstrated higher collagen fraction in gel-treated wounds. Thus, from the results, it could be concluded that pluronic F-127 gel has a mild inflammatory nature and enhanced the healing by stimulating expression of VEGF and TGF-ß1.

Antihyperalgesic and anti-inflammatory effects of atorvastatin in chronic constriction injury-induced neuropathic pain in rats.

Atorvastatin is a 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitor used in treatment of hypercholesterolemia and prevention of coronary heart disease. The aim of this study is to investigate the antihyperalgesic and anti-inflammatory effects of atorvastatin (3, 10, and 30 mg/kg by oral gavages for 14 days) in chronic constriction injury (CCI) model of neuropathic pain in rats. CCI caused significant increase in tumor necrosis factor-α, interleukin 1 beta, prostaglandin E2, along with matrix metalloproteases (MMP-2) and nerve growth factor (NGF) levels in sciatic nerve and spinal cord concomitant with mechanical and thermal hyperalgesia, which were significantly reduced by oral administration of atorvastatin for 14 days as compared to CCI rats. Our study demonstrated that atorvastatin attenuates neuropathic pain through inhibition of cytokines, MMP-2, and NGF in sciatic nerve and spinal cord suggesting that atorvastatin could be an additional therapeutic strategy in management of neuropathic pain.

Effect of iNOS inhibitor S-methylisothiourea in monosodium iodoacetate-induced osteoathritic pain: implication for osteoarthritis therapy.

Much information is available on the role of nitric oxide (NO) in osteoarthritis (OA). However, its role has not been studied in the monosodium iodoacetate (MIA)-induced model of osteoarthritic pain. The present study was undertaken in rats to investigate the effect of iNOS inhibitor S-methylisothiourea (SMT) in MIA-induced osteoathritic pain and disease progression in rats. Osteoarthritis was produced by single intra-articular injection of the MIA in the right knee joint on day 0. Treatment groups were orally gavazed with different doses of SMT (10, 30 and 100mg/kg) and etoricoxib (10mg/kg) daily for 21 days. On days 0, 3, 7, 14 and 21, pain was measured and histopathology of right knee joint was done on day 21. SMT produced analgesia in a dose-dependent manner as shown by mechanical, heat hyperalgesia, knee vocalization, knee squeeze test, and spontaneous motor activity test. SMT reduced NO production in synovial fluid. Histopathological findings indicated that SMT reduced disease progression as evident from complete cartilage formation in rats treated with SMT at 30 mg/kg. In conclusion, the results indicate that SMT attenuates the MIA-induced pain and histopathological changes in the knee joint. The antinociceptive and antiarthritic effects of SMT were mediated by inhibiting cartilage damage and suppression of NO in synovial fluid. It is suggested that SMT has potential as a therapeutic modality in the treatment of osteoarthritis.

Feeding standards for lactating riverine buffaloes in tropical conditions.

Data from 33 feeding trials, conducted on lactating riverine buffaloes from different institutes across India, were subjected to multiple regression analysis to derive nutritional requirements for dry matter (DM), total digestible nutrients (TDN), crude protein (CP) and digestible crude protein (DCP) for maintenance, milk production and body weight gain. Maintenance requirements for DM, TDN, CP and DCP were 59.9, 35.3, 5.43 and 3.14 g/kgW(0.75), respectively; corresponding requirements for producing 1 kg 6% FCM were 688, 406, 90.3 and 55.2 g and for 1 g gain in body weight were 3.37, 1.97, 0.327 and 0.23 g. Regression equations had high R2 values (061. 0.66, 0.84 and 0.68 for prediction of DM, TDN, CP and DCP, respectively) and the equations (F-value) as well as coefficients were highly significant (P <0.001). Regressed values were used to derive feeding standards. Derived values matched well with the actual intake versus performance of animals under diverse feeding conditions. New standards predicted requirements and intake of nutrients for different production levels better than existing feeding standards. Because they are based on a more thorough analysis of data, the new feeding standards will be appropriate for use widely in India.