Mechanistic insights into carbonic anhydrase IX inhibition by coumarins from Calendula officinalis: in vitro and in silico approaches.

Given the critical role of carbonic anhydrase IX (CA IX) in various pathological conditions, there is a significant demand for new inhibitors to enhance patient outcomes and clinical management. In this study, we examined the inhibitory effectiveness of five coumarins derived from Calendula officinalis against CA IX using in vitro assays and computational modeling. Among the coumarins tested, xeroboside and isobaisseoside were identified as the most potent inhibitors. Kinetic studies indicated that xeroboside and isobaisseoside exhibit a mixed inhibition mode. Molecular docking analysis showed that the tested coumarins exhibit binding affinities and extensive polar interactions with CA IX. These coumarins demonstrated significant hydrophobic interactions and occupied the same binding site as acetazolamide (AAZ). Molecular dynamics (MD) indicated that xeroboside and isobaisseoside exhibited consistent trajectories and notable energy stabilization during their interaction with CA IX. MM/PBSA calculations showed that xeroboside displayed the lowest binding free energy (-27.26 ± 2.48 kJ mol-1). Potential Energy Landscape (PEL) analysis revealed distinct and stable conformational states for the CA IX-ligand complexes, with xeroboside exhibiting the most stable and lowest energy configuration. These computational findings are consistent with the experimental results, highlighting the potential efficacy of xeroboside and isobaisseoside as CA IX inhibitors. In conclusion, Calendula officinalis-derived coumarins are promising candidates as effective CA IX inhibitors.

Diallyl Disulfide Mitigates Cadmium Hepatotoxicity by Attenuating Oxidative Stress and TLR-4/NF-κB Signaling and Upregulating PPARγ.

BACKGROUND: Heavy metals can cause serious health problems that affect different organs. Cadmium (Cd) is an environmental contaminant known for its toxicological consequences on different organs. Hepatotoxicity is a serious effect of exposure to Cd with oxidative stress (OS) and inflammation playing a central role. Diallyl disulfide (DADS), an organo-sulfur compound found in garlic, is known for its cytoprotective and antioxidant effects. In this study, the effect of DADS on Cd-induced inflammation, oxidative stress and liver injury was investigated. METHODS: DADS was supplemented for 14 days via oral gavage, and a single intraperitoneal dose of Cd (1.2 mg/kg body weight) was administered to rats on day 7. Blood and liver samples were collected at the end of the experiment for analyses. RESULTS: Cd administration resulted in remarkable hepatic dysfunction, degenerative changes, necrosis, infiltration of inflammatory cells, collagen deposition and other histopathological alterations. Cd increased liver malondialdehyde (MDA) and nitric oxide (NO) (p < 0.001), upregulated toll-like receptor (TLR)-4, nuclear factor-kappaB (NF-κB), pro-inflammatory mediators, and caspase-3 (p < 0.001) whereas decreased glutathione (GSH) and antioxidant enzymes (p < 0.001). Cd downregulated peroxisome proliferator activated receptor gamma (PPARγ), a transcription factor involved in inflammation and OS suppression (p < 0.001). DADS ameliorated liver injury and tissue alterations, attenuated OS and apoptosis, suppressed TLR-4/NF-κB signaling, and enhanced antioxidants. In addition, DADS upregulated PPARγ in the liver of Cd-administered rats. CONCLUSIONS: DADS is effective against Cd-induced hepatotoxicity and its beneficial effects are linked to suppression of inflammation, OS and apoptosis and upregulation of PPARγ. DADS could be valuable to protect the liver in individuals at risk of Cd exposure, pending further studies to elucidate other underlying mechanism(s).

Attenuation of inflammation, oxidative stress and TGF-ß1/Smad3 signaling and upregulation of Nrf2/HO-1 signaling mediate the protective effect of diallyl disulfide against cadmium nephrotoxicity.

Heavy metals are toxic environmental pollutants with serious health effects on humans and animals. Cadmium (Cd) is known for its serious nephrotoxic effect and its toxicity involves oxidative stress (OS) and inflammation. Diallyl disulfide (DADS), a main constituent of garlic, exhibites cytoprotective and antioxidant activities. This study investigated the effect of DADS on OS, inflammation, and fibrosis induced by Cd in rat kidney, pointing to the involvement of transforming growth factor-ß (TGF-ß)/Smad3 and nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling, and peroxisome proliferator-activated receptor gamma (PPARγ). Rats received DADS for 14 days and Cd on day 7 and blood and kidney samples were collected. Cd elevated serum creatinine, urea and uric acid, provoked kidney histopathological alterations and collagen deposition, increased kidney malondialdehyde (MDA) level, and decreased glutathione (GSH) and antioxidant enzymes. Nuclear factor-kappaB (NF-κB) p65, interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-1ß, and CD68 were upregulated in Cd-administered rat kidney. DADS prevented kidney injury, mitigated OS, suppressed NF-κB, CD68 and pro-inflammatory mediators, and boosted antioxidants. DADS downregulated TGF-ß1, Smad3 phosphorylation and Kelch-like ECH-associated protein-1 (Keap1), and increased Nrf2, HO-1, cytoglobin, and PPARγ. In conclusion, DADS protects the kidney against Cd toxicity by attenuating OS, inflammation, and TGF-ß1/Smad3 signaling, and enhancement of Nrf2/HO-1 signaling, antioxidants, and PPARγ.

Haloxylon salicornicum Phytochemicals Suppress NF-kB, iNOS and Pro-inflammatory Cytokines in Lipopolysaccharide-Induced Macrophages.

Haloxylon salicornicum is traditionally used for the treatment of several disorders associated with inflammation. Despite it is a defense response against tissue injury and infections, inflammation can become a chronic condition that can negatively impact the body. This study investigated the effect of H. salicornicum phytochemicals nuclear factor-kappaB (NF-κB), inducible nitric oxide synthase (iNOS) and cytokines release by lipopolysaccharide (LPS)-challenged macrophages in vitro. The binding affinity of the tested phytochemical towards NF-κB and iNOS was investigated using molecular docking. Ten compounds (four coumarins, three sterols and three flavonoids) were isolated from the ethanolic extract of H. salicornicum. Treatment of LPS-challenged macrophages with the compounds resulted in remarkable decrease in NF-κB p65 and iNOS mRNA abundance. All compounds suppressed the production of nitric oxide (NO) and the pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-6) from macrophages challenged with LPS. Molecular docking revealed the ability of the isolated phytochemicals to bind NF-κB p65 and iNOS. In conclusion, H. salicornicum is a rich source of phytochemicals with anti-inflammatory properties. The anti-inflammatory efficacy of H. salicornicum phytoconstituents is mediated via their ability to modulate NF-κB and iNOS, and suppress the release of NO, TNF-α, and IL-6 from macrophages.

Farnesol attenuates cadmium-induced kidney injury by mitigating oxidative stress, inflammation and necroptosis and upregulating cytoglobin and PPARγ in rats.

Heavy metals are environmental pollutants that can harm animals and humans even at low concentrations. Cadmium (Cd) is known for its serious health effects on different organs and its toxicity is associated with oxidative stress (OS) and inflammation. Farnesol (FAR), a sesquiterpene alcohol found in many vegetables and fruits, possesses promising anti-inflammatory and antioxidant activities. This study evaluated the effect of FAR on Cd-induced kidney injury, pinpointing its effect of the redox status, inflammation, fibrosis and necroptosis. Rats in this study received FAR for 14 days and Cd on day 7. Elevated serum creatinine, urea and uric acid, and several kidney histopathological alterations were observed in Cd-administered rats. Cd increased MDA, decreased antioxidants, downregulated PPARγ and upregulated NF-κB p65, IL-6, TNF-α, and IL-1ß. Necroptosis mediators (RIP1, RIP3, MLKL, and caspase-8) and α-SMA were upregulated, and collagen deposition was increased in Cd-administered rats. FAR ameliorated kidney injury markers and tissue damage, attenuated OS, suppressed NF-κB and inflammatory mediators, and enhanced antioxidants. In addition, FAR suppressed RIP1, RIP3, MLKL, caspase-8, and α-SMA, and enhanced kidney cytoglobin and PPARγ. In conclusion, FAR protects against Cd nephrotoxicity by suppressing OS, inflammatory response and necroptosis, effects associated with enhanced antioxidants, cytoglobin, and PPARγ.

Phytochemical Analysis and Anti-dyslipidemia and Antioxidant Activities of Pluchea dioscoridis: In Vitro, In Silico and In Vivo Studies.

Pluchea dioscoridis (L.) DC. is a flowering wild plant used traditionally in the treatment of rhematic disorders. This study investigated the phytochemical and in vitro radical scavenging activity (RSA), and in vivo anti-hyperlipidemic, antioxidant and anti-inflammatory properties of P. dioscoridis. The antihyperlipidemic efficacy was determined in a rat model of dyslipidemia. The extract and fractions of P. dioscoridis showed RSA with the ethyl acetate (EA) fraction exhibiting the most potent activity. The phytochemical analysis of P. dioscoridis EA fraction (PDEAF) led to the isolation of five compounds (lupeol, quercetin, lupeol acetate, stigmasterol, and syringic acid). To evaluate its anti-hyperlipidemic effect, three doses of PDEAF were supplemented to rats for 14 days and poloxamer-407 was administered on day 15 to induce dyslipidemia. All doses of PDEAF decreased plasma triglycerides, cholesterol, low-density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein-cholesterol (vLDL-C), and increased plasma lipoprotein lipase (LPL). PDEAF upregulated hepatic LDL receptor and suppressed 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, decreased lipid peroxidation and tumor necrosis factor (TNF)-α and enhanced reduced glutathione (GSH) and enzymatic antioxidants in dyslipidmeic rats. In silico findings revealed the binding affinity of the isolated compounds towards LPL, HMG-CoA reductase, and LDL receptor. In conclusion, P. dioscoridis is rich in phytoconstituents, exhibited RSA and its EA fraction effectively prevented acute dyslipidemia and its associated oxidative stress and inflammatory response.

Farnesol prevents chlorpyrifos nephrotoxicity by modulating inflammatory mediators, Nrf2 and FXR and attenuating oxidative stress.

Chlorpyrifos (CPF) is a broad-spectrum insecticide widely employed in agricultural field for pest control. Exposure to CPF is associated with serious effects to the main organs, including kidneys. Significant evidence denotes that oxidative stress (OS) and inflammation are implicated in CPF toxicity. This study aimed to evaluate the potential of farnesol (FAR) to modulate inflammatory mediators and farnesoid-X-receptor (FXR) and Nrf2 in a rat model of CPF nephrotoxicity. CPF and FAR were orally supplemented for 28 days and blood and kidney samples were collected for investigations. CPF administration elevated blood creatinine and urea, kidney MDA and NO, and upregulated NF-κB p65, IL-1ß, TNF-α, iNOS, and caspase-3. In addition, CPF upregulated kidney Keap1, and decreased GSH, antioxidant enzymes, and Nrf2, FXR, HO-1 and NQO-1. FAR ameliorated creatinine and urea, prevented histopathological alterations, decreased MDA and NO, and enhanced antioxidants in CPF-administered rats. FAR modulated NF-κB p65, iNOS, TNF-α, IL-1ß, caspase-3, Keap1, HO-1, NQO-1, Nrf2 and FXR. In silico investigations revealed the binding affinity of FAR towards Keap1 and FXR, as well as NF-κB, caspase-3, iNOS, and HO-1. In conclusion, FAR prevents CPF-induced kidney injury by attenuating OS, inflammation, and apoptosis, effects associated with modulation of FXR, Nrf2/HO-1 signaling and antioxidants.

Arbutin ameliorates hyperglycemia, dyslipidemia and oxidative stress and modulates adipocytokines and PPARγ in high-fat diet/streptozotocin-induced diabetic rats.

Arbutin is a glycosylated hydroquinone with antioxidant and anti-hyperglycemia effects. However, its beneficial effects in type 2 diabetes (T2D) were not clarified. This study evaluated the effect of arbutin on hyperglycemia, dyslipidemia, insulin resistance, oxidative stress, and inflammatory response in T2D. Rats induced by high fat diet and streptozotocin were treated with arbutin (25 and 50 mg/kg) for 4 weeks. Diabetic rats exhibited glucose intolerance, elevated HbA1c%, reduced insulin, and high HOMA-IR. Liver glycogen and hexokinase activity were decreased in T2D rats while glucose-6-phosphatase (G6Pase), fructose-1,6- biphosphatase (FBPase), and glycogen phosphorylase were upregulated. Circulating and hepatic cholesterol and triglycerides and serum transaminases were elevated in T2D rats. Arbutin ameliorated hyperglycemia, dyslipidemia, insulin deficiency and resistance, and liver glycogen and alleviated the activity of carbohydrate-metabolizing enzymes. Both doses of arbutin decreased serum transaminases and resistin, and liver lipids, TNF-α, IL-6, malondialdehyde and nitric oxide, downregulated liver resistin and fatty acid synthase, and increased serum and liver adiponectin, and liver reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). These effects were associated with the upregulation of hepatic PPARγ. Arbutin inhibited α-glucosidase in vitro and in silico investigations revealed the ability of arbutin to bind PPARγ, hexokinase, and α-glucosidase. In conclusion, arbutin effectively ameliorated glucose intolerance, insulin resistance, dyslipidemia, inflammation, and oxidative stress, and modulated carbohydrate-metabolizing enzymes, antioxidants, adipokines and PPARγ in T2D in rats.

A flavonoid-rich fraction of Monolluma quadrangula inhibits xanthine oxidase and ameliorates potassium oxonate-induced hyperuricemia in rats.

Hyperuricemia represents a risk factor for the progression of chronic kidney disease. Oxidative stress and inflammation are implicated in the mechanisms underlying hyperuricemia-mediated kidney injury. Monolluma quadrangula possesses several beneficial effects; however, its effect on hyperuricemia has not been investigated. This study evaluated the renoprotective and xanthine oxidase (XO) inhibitory activity of M. quadrangula in hyperuricemic rats. Phytochemical investigation revealed the presence of six known flavonoid isolated for the first time from this species. The rats received M. quadrangula extract (MQE) and potassium oxonate (PO) for 7 days. In vitro assays showed the radical scavenging and XO inhibitory activities of MQE, and in silico molecular docking revealed the inhibitory activity of the isolated flavonoids towards XO. Hyperuricemic rats showed elevated serum uric acid, creatinine, urea, and XO activity, and renal pro-inflammatory cytokines, MDA and NO, and decreased GSH, SOD, and catalase. MQE ameliorated serum uric acid, urea, creatinine, and XO activity, and renal pro-inflammatory cytokines. In addition, MQE attenuated renal oxidative stress, enhanced antioxidants, downregulated URAT-1, and GLUT-9 and upregulated OAT-1 in PO-induced rats. In conclusion, M. quadrangula attenuated hyperuricemia and kidney impairment by suppressing XO activity, oxidative stress and inflammation, and modulating urate transporters.

Azithromycin Mitigates Cisplatin-Induced Lung Oxidative Stress, Inflammation and Necroptosis by Upregulating SIRT1, PPARγ, and Nrf2/HO-1 Signaling.

Acute lung injury (ALI) is one of the adverse effects of the antineoplastic agent cisplatin (CIS). Oxidative stress, inflammation, and necroptosis are linked to the emergence of lung injury in various disorders. This study evaluated the effect of the macrolide antibiotic azithromycin (AZM) on oxidative stress, inflammatory response, and necroptosis in the lungs of CIS-administered rats, pinpointing the involvement of PPARγ, SIRT1, and Nrf2/HO-1 signaling. The rats received AZM for 10 days and a single dose of CIS on the 7th day. CIS provoked bronchial and alveolar injury along with increased levels of ROS, MDA, NO, MPO, NF-κB p65, TNF-α, and IL-1ß, and decreased levels of GSH, SOD, GST, and IL-10, denoting oxidative and inflammatory responses. The necroptosis-related proteins RIP1, RIP3, MLKL, and caspase-8 were upregulated in CIS-treated rats. AZM effectively prevented lung tissue injury, ameliorated oxidative stress and NF-κB p65 and pro-inflammatory markers levels, boosted antioxidants and IL-10, and downregulated necroptosis-related proteins in CIS-administered rats. AZM decreased the concentration of Ang II and increased those of Ang (1-7), cytoglobin, PPARγ, SIRT1, Nrf2, and HO-1 in the lungs of CIS-treated rats. In conclusion, AZM attenuated the lung injury provoked by CIS in rats through the suppression of inflammation, oxidative stress, and necroptosis. The protective effect of AZM was associated with the upregulation of Nrf2/HO-1 signaling, cytoglobin, PPARγ, and SIRT1.

Agomelatine prevents gentamicin nephrotoxicity by attenuating oxidative stress and TLR-4 signaling, and upregulating PPARγ and SIRT1.

Kidney injury is a relatively common complication of the use of aminoglycosides. Inflammation and oxidative stress play a key role in gentamicin (GM) nephrotoxicity. We investigated the protective effect of the melatonergic agonist agomelatine (AGM) on GM nephrotoxicity, emphasizing the involvement of TLR-4 signaling, SIRT1 and PPARγ. Rats received 25 mg/kg AGM for 15 days and 100 mg/kg GM for eight days starting at day 7. Elevated serum creatinine, urea and Kim-1 along with multiple histological alterations in the kidney were observed in GM-intoxicated rats. Malondialdehyde (MDA), TNF-α, IL-1ß, nitric oxide (NO) and myeloperoxidase (MPO) were increased, and GSH, SOD and catalase were decreased in the kidney of GM-intoxicated rats. Treatment with AGM significantly ameliorated the kidney function biomarkers, prevented tissue injury, decreased inflammatory cytokines, MDA, NO and MPO, and boosted antioxidants. In addition, AGM suppressed the expression of TLR-4, NF-κB p65, p38 MAPK, ERK-1, VCAM-1 and iNOS, whereas upregulated SIRT1 and PPARγ in the kidney of GM-intoxicated rats. In conclusion, AGM prevented GM nephrotoxicity in rats by attenuating oxidative injury and inflammation. AGM suppressed TLR-4 signaling, enhanced antioxidants and upregulated SIRT1 and PPARγ in the kidney of GM-induced rats.

Umbelliferone Inhibits Spermatogenic Defects and Testicular Injury in Lead-Intoxicated Rats by Suppressing Oxidative Stress and Inflammation, and Improving Nrf2/HO-1 Signaling.

INTRODUCTION: Lead (Pb) is an environmental toxic metal that threatens human health. Umbelliferone (UMB) is a coumarin with known medicinal and protective properties against cytotoxicity. This study explored the ameliorative effect of UMB against Pb-induced testicular toxicity in rats, focusing on steroidogenesis, oxidative stress and inflammation. MATERIALS AND METHODS: Rats received lead acetate (50 mg/kg) and UMB (25, 50 or 100 mg/kg) via oral gavage for 4 weeks. RESULTS: Pb-intoxicated rats exhibited testicular tissue injury and decreased serum levels of LH, FSH and testosterone. The count, viability, motility and normal morphology of the sperms were decreased accompanied with downregulated steroidogenesis markers in Pb-induced group. UMB prevented testicular injury, increased serum levels of LH, FSH and testosterone, upregulated steroidogenesis markers and improved the semen quality. In addition, UMB attenuated oxidative stress and oxidative DNA damage, downregulated the expression of pro-inflammatory mediators and Bax, boosted antioxidant defenses and Bcl-2, and upregulated Nrf2/HO-1 signaling in Pb-intoxicated rats. CONCLUSION: UMB prevents Pb-induced testicular injury by suppressing oxidative damage, inflammation and cell death, and boosting antioxidant defenses, Nrf2/HO-1 signaling and pituitary-gonadal axis. Thus, UMB may represent a protective and cost-effective agent against Pb testicular toxicity, pending further investigations to elucidate other underlying mechanisms.

The effect of Ramadan intermittent fasting on lipid peroxidation in healthy young men while controlling for diet and sleep: A pilot study.

AIMS: We hypothesized that if we control for lifestyle changes during Ramadan, Ramadan Islamic intermittent fasting (IF) reduces oxidative stress. This study was conducted to examine the effect of Islamic IF during and outside of Ramadan on the circadian changes in lipid peroxidation marker malondialdehyde (MDA) during and outside while controlling for potential confounders. METHODS: Serum MDA concentration was measured in eight healthy male volunteers at baseline (BL), after fasting for 1 week before Ramadan (BL fasting), and during Ramadan. Blood samples were drawn at 22:00, 02:00, 04:00, 06:00, and 11:00. The participants were admitted to the sleep laboratory and monitored for 24 h on the day of the measurements. In the laboratory, each participant received meals of fixed compositions and caloric contents based on their ideal body weights. Light exposure, physical activity, and total sleep duration were uniformly maintained during the three study periods. RESULTS: The participants had a mean age of 26.6 ± 4.9 years and a mean body mass index of 23.7 ± 3.5 kg/m(2). No significant changes were observed in MDA levels and blood glucose during BL, BL fasting, or Ramadan. CONCLUSION: In this pilot study, under conditions of fixed sleep-wake schedules and caloric intake, Ramadan IF does not alter serum MDA levels in healthy subjects. Larger studies are needed to confirm these findings.

The time course of cytokine expressions plays a determining role in faster healing of intestinal and colonic anastomatic wounds.

OBJECTIVES: Inflammation is critical in the early phases of wound healing. It has been reported previously that small intestinal and colonic wounds display a more rapid healing than those of other organs. However, the underlying mechanism has not yet been elucidated. Here we examined whether differences in the time course of specified cytokine expression, in colonic and small intestinal anastomotic lesions, might play a major role in this observation in comparison to lesions effecting skin and muscle tissue. MATERIALS AND METHODS: Tissue lesions were applied to 36 male Sprague-Dawley rats. Tissue samples were harvested at 1, 3, 5, 7, and 14 days postoperatively with the levels of TNF-α, IL-6, and IFN-α determined by ELISA-derived methods. RESULTS: The characteristics of TNF-α, IL-6, and IFN-α expression during the healing process for intestinal and colonic lesions were comparable. However, data differed significantly with that observed during healing of skin and muscle lesions. Intestinal and colonic lesions exhibited a significant and sustained increase in specified cytokine levels on day 5 to day 14 as compared with day 1 and 3. Skin and muscle lesions had random or unaltered cytokine levels throughout the study period. CONCLUSION: Differences in expression of cytokines TNF-α, IL-6, and IFN-α indicate that these play an important role underlying the more rapid healing processes observed in small intestinal and colonic lesions.

Relationship of the Arabic version of the asthma control test with ventilatory function tests and levels of exhaled nitric oxide in adult asthmatics.

OBJECTIVE: To determine the relationship between the asthma control test (ACT) score using the Arabic version, fractional exhaled nitric oxide (FENO), and lung functions, and to derive the cutoff points for the ACT score with the American Thoracic Society recommended FENO standard levels of inflammation control. METHODS: We recruited 59 adult asthmatics out of which 53 subjects completed the study between July 2011 and June 2012 at King Saud University, Riyadh, Saudi Arabia. The FENO levels were measured by NIOX MINO (Aerocrine AB, Solna, Sweden), and ventilatory functions were recorded by standard techniques. RESULTS: The FENO values were significantly higher in patients with an ACT score <20 (65.5+/= 35.4) compared with those patients with an ACT score >/= 20 (27.4+/=10.5, p<0.001). Among the well-controlled group based on the ACT score criteria, 6 (25%) cases had high FENO levels, while among the poorly controlled group, 23 (79.3%) cases had high FENO levels (odds ratio: 11.5; p<0.0001; confidence interval: 3.16-41.72). There was a significant negative correlation between FENO and ACT score (r=-0.581, p<0.0001). At the international cutoff point of 20, the sensitivity was 95.2, and the specificity was 68.8. The receiver operating curve (ROC) showed that maximum sensitivity and specificity were observed at an ACT score cut off point of 19 (sensitivity: 90.5, and specificity: 81.2). CONCLUSION: The FENO levels correlate negatively with ACT scores however, the relationship between FENO and lung function is not significant. A significant relationship between ACT score and FENO levels indicate that there is an ongoing inflammatory state in patients with poor asthma control.

Diurnal intermittent fasting during Ramadan: the effects on leptin and ghrelin levels.

We aimed to assess the effect of Islamic intermittent fasting, during and outside of Ramadan, on plasma levels of leptin and ghrelin while controlling for several potential confounding variables. Eight healthy male volunteers with a mean age of 26.6±4.9 years reported to the sleep disorders center (SDC) at King Saud University on four occasions: 1) adaptation; 2) 4 weeks before Ramadan while performing Islamic fasting for 1 week (baseline fasting) (BLF); 3) 1 week before Ramadan (non-fasting baseline) (BL); and 4) during the second week of Ramadan while fasting. Plasma leptin and ghrelin levels were measured using enzyme-linked immunoassays at 22:00, 02:00, 04:00, 06:00, and 11:00. During BLF, there were significant reductions in plasma leptin concentrations at 22:00 and 02:00 compared with the baseline concentrations (at 22:00: 194.2±177.2 vs. 146.7±174.5; at 02:00: 203.8±189.5 vs. 168.1±178.1; p<0.05). During Ramadan, there was a significant reduction in plasma leptin levels at 22:00 (194.2±177.2 vs. 132.6±130.4, p<0.05). No significant difference in plasma ghrelin concentrations was detected during the BL, BLF, or Ramadan periods. Cosinor analyses of leptin and ghrelin plasma levels revealed no significant changes in the acrophases of the hormones during the three periods. The nocturnal reduction in plasma leptin levels during fasting may be the result of the changes in meal times during fasting.

Temporal expression of IL-1ß and IL-10 in rat skin, muscle, small bowel, and colon wounds: a correlative study.

BACKGROUND: Cytokines play a major role in coordinated wound healing events. We hypothesized that rapid intestinal healing is due to an early upregulation of the pro-inflammatory cytokine interleukin-1ß (IL-1ß), followed by increases in the expression of the anti-inflammatory cytokine IL-10. METHODS: We characterized the time course of IL-1ß and IL-10 release at four wounds (skin, muscle, small bowel, and colonic anastomosis) after surgery on 38 juvenile male Sprague-Dawley rats. The tissue samples of each site were harvested at 0 (control), 1, 3, 5, 7, and 14 days postoperatively (n=6-8 per group) and analyzed by enzyme-linked immunosorbent assay kits for IL-1ß and IL-10. RESULTS: IL-1ß expression peaked at days 5 and 7 in small bowel and colonic wounds when compared to skin or muscle. Similarly, IL-10 showed high expression in these time points in small bowel and colonic wounds. However, IL-10 showed the same expression in all time points in muscle and skin tissues except at day 1. CONCLUSIONS: The high expression in IL-1ß and IL-10 levels in small bowel and colon might explain the accelerated healing process in these wounds in comparison to skin and muscle tissues. Additional studies are required to determine whether IL-1ß and IL-10 expression is the major factor defining site-specific differences in healing rates in different tissues. Understanding cytokine action in the wound healing process could lead to novel and effective therapeutic strategies.

Antioxidant activities for superoxide dismutase in patients with Crohn's disease.

BACKGROUND: In this study, we aimed to determine the levels of antioxidant activity for superoxide dismutase (SOD) enzymes in patients with Crohn's disease (CD) to investigate their contribution to tissue injury in CD. METHODS: Forty-two patients with CD and 38 matched healthy subjects (control group) were recruited. SOD enzymatic activity was measured by purely chemical system based on NAD(P)H oxidation. RESULTS: Plasma antioxidant activities for SOD in CD patients were significantly lower than that in the control group. CONCLUSIONS: Low antioxidant activity for SOD in CD is an important indication of oxidative stress. CD patients are more susceptible to oxidative stress. This study supports the hypothesis that increased oxidative stress and decreased antioxidant defense in CD.

Upregulation of the proinflammatory cytokine-induced neutrophil chemoattractant-1 and monocyte chemoattractant protein-1 in rats' intestinal anastomotic wound healing--does it matter?

BACKGROUND: The proinflammatory cytokines and growth-promoting factor are essential components of the wound healing process. We hypothesized that under healthy conditions, faster healing of intestinal anastomotic wound is due to an early upregulation of proinflammatory cytokines, cytokine-induced neutrophil chemoattractant-1 (CINC-1) that is followed by a quicker upregulation of homeostatic chemokine, monocyte chemoattractant protein-1 (MCP-1) and late upregulation of transforming growth factor (TGF-ß). METHODS: We characterized the time course of CINC-1, MCP-1 and TGF-ß release at four wounds (skin, muscle, small bowel, and colonic anastomosis) after surgery on 38 juvenile male Sprague Dawley rats. The tissue samples of each site were harvested at 0 (control), 1, 3, 5, 7 and 14 days postoperatively (n = 6-8/group) and analyzed by ELISA kits for CINC-1, MCP-1 and TGF-ß. RESULTS: CINC-1 expression peaked earlier in muscle and colonic wounds when compared to skin and small bowel. MCP-1 levels were elevated early in skin and muscle wounds, but later expression of MCP-1 was shown in colonic wounds. TGF-ß levels were unchanged in all wound sites. CONCLUSION: An earlier peak in CINC-1 levels and later expression of MCP-1 were seen in colonic wounds, but no significant increase in TGF-ß levels was observed. These findings support the early healing process in intestinal anastomotic wounds.

Concepts of oxidative stress and antioxidant defense in Crohn's disease.

Oxygen free radical and lipid peroxides (oxidative stress) are highly reactive and represent very damaging compounds. Oxidative stress could be a major contributing factor to the tissue injury and fibrosis that characterize Crohn's disease. An imbalance between increased reactive oxygen species levels and decreased antioxidant defenses occurs in Crohn's patients. Decreased blood levels of vitamins C and E and decreased intestinal mucosal levels of CuZn superoxide dismutase, glutathione, vitamin A, C, E, and ß-carotene have been reported for Crohn's patients. Increased levels of proinflammatory cytokines, such as interleukin-1 and -8 and tumor necrosis factor, have been detected in inflammatory bowel disease. Oxidative stress significantly increased the production of neutrophils, chemokines, and interleukin-8. These effects were inhibited by antioxidant vitamins and arachidonic acid metabolite inhibitors in human intestinal smooth muscle cells isolated from the bowels of Crohn's disease patients. The main pathological feature of Crohn's disease is an infiltration of polymorphonuclear neutrophils and mononuclear cells into the affected part of the intestine. Activated neutrophils produce noxious substances that cause inflammation and tissue injury. Due to the physiological and biochemical actions of reactive oxygen species and lipid peroxides, many of the clinical and pathophysiological features of Crohn's disease might be explained by an imbalance of increased reactive oxygen species and a net decrease of antioxidant molecules. This review describes the general concepts of free radical, lipid peroxide and antioxidant activities and eventually illustrates their interferences in the development of Crohn's strictures.