Improvement of tissue survival of skin flaps by 5 alpha-reductase inhibitors: possible involvement of nitric oxide and inducible nitric oxide synthase

Skin flap grafting is a popular approach for reconstruction of critical skin and underlying soft tissue injuries. In a previous study, we demonstrated the beneficial effects of two 5alpha-reductase inhibitors, azelaic acid and finasteride, on tissue survival in a rat model of skin flap grafting. In the current study, we investigated the involvement of nitric oxide and inducible nitric oxide synthase [iNOS] in graft survival mediated by these agents. A number of 42 male rats were randomly allocated into six groups: 1, normal saline topical application; 2, azelaic acid [100 mg/flap]; 3, finasteride [1 mg/flap]; 4, injection of L-N[G]-nitroarginine methyl ester [L-NAME] [i.p., 20 mg/kg]; 5, L-NAME [20 mg/kg, i.p.] + azelaic acid [100 mg/flap, topical]; 6, L-NAME [20 mg/kg, i.p.] + finasteride [1 mg/flap, topical]. Tissue survival, level of nitric oxide, and iNOS expression in groups were measured. Our data revealed that azelaic acid and finasteride significantly increased the expression of iNOS protein and nitric oxide [NO] levels in graft tissue [P < 0.05]. These increases in iNOS expression and NO level were associated with higher survival of the graft tissue. It appears that alterations of the NO metabolism are implicated in the azelaic acid- and finasteride-mediated survival of the skin flaps

effect of pomegranate extract on survival and peritoneal bacterial load in cecal ligation and perforation model of sepsis in rats

Sepsis is one of the major causes of death in intensive care units. Oxidative stress and hyper-inflammation has been shown to be major cause of mortality and morbidity in septic cases. Pomegranate is a fruit considered for its antioxidant and anti-inflammatory properties. The aim of this study is to evaluate the effect of a standard pomegranate fruit liquid extract[POMx], on mortality and peritoneal bacterial load in cecal ligation and perforation [CLP] sepsis model. Male wistar rats were divided into four groups of 24 each: sham; CLP; prevention [consumed POMx [250 mg of polyphenols/kg/day] for 4 weeks before CLP]; treatment [received a single drink of POMx [250 mg of polyphenols/kg] after CLP]. Each group was divided into three subgroups, each containing eight animals, for bacterial load and survival [with and without antibiotics] studies. Sepsis was induced by CLP surgery. Ten day survival rate was recorded. Peritoneal bacterial load was also assessed. Data were analyzed using Log-rank and Kruskal-Wallis tests. There was no significant difference in survival rate of CLP, prevention and treatment groups, in subgroups without antibiotics. However, in subgroups with antibiotics, the prevention group had significantly lower survival rate than sham group [P 0.05]. Conversely, the bacterial load of prevention and treatment groups were significantly higher than sham group [P< 0.01]. Our study demonstrates for the first time that pomegranate extract could increase mortality rate via increasing peritoneal cavity bacterial load, in CLP sepsis model. More studies to assess mechanisms of this effect are warranted

Caffeine treatment prevented from weight regain after calorie shifting diet induced weight loss

Low calorie diets are always difficult for obese subjects to follow and lead to metabolic and behavioral adaptation. Therefore, we evaluated the effect of caffeine treatment with calorie shifting diet [CSD] on weight loss. Female subjects [n=60; BMI>25] completed 4-weeks control diet, 6-weeks CSD [3 repeated phases; each 2-weeks] and 4-weeks follow-up diet, with or without caffeine treatment [5 mg/Kg/day]. The first 11 days of each phase included calorie restriction with four meals every day and 4 hours intervals. Significant weight and fat loss were observed after 4-weeks of CSD [5.7 +/- 1.24 Kg and 4.84 +/- 1.53 Kg] or CSD+Caffeine [7.57 +/- 2.33 Kg and 5.24 +/- 2.07 Kg] which was consistent for one month of the follow-up [CSD: 5.24 +/- 1.83 Kg and 4.3 +/- 1.62 Kg, CSD+Caffeine: 12.11 +/- 2.31 Kg and 9.85 +/- 1.6 Kg, p < 0.05 vs CSD group] and correlated to the restricted energy intake [p < 0.05]. During three CSD phases. RMR tended to remain unchanged in both groups. While, CSD or CSD + Caffeine treatments, significantly decreased plasma glucose, total-cholesterol, and triacylglycerol [p < 0.05], even during follow-up period [p < 0.05]. HDL-cholesterol was not changed by CSD. Feeling of hunger decreased and subject's satisfaction increased after 4-weeks of CSD [p < 0.05] and remained low to the end of study, while satiety was not affected. Coffeine increased the effect of CSD on feeling of hunger and subject's satisfaction after week 7 [p < 0.05 vs. CSD]. These findings indicated that combination of caffeine treatment with CSD could be an effective alternative approach to weight and fat loss with small changes in RMR and improved tolerance of subjects to the new diet

[Effects of diazoxide on rat isolated atria]

It is generally accepted that the selective adenosine triphosphatedependent potassium channel openers [K[ATP] openers] have a dramatic role in the treatment of some cardiovascular disorders. The aim of this study was to investigate the effects of diazoxide, a potent ATP-related potassium channel opener, on spontaneously beating isolated rat atria to achieve more accurate approaches to treat cardiovascular diseases, such as atrial related disorders including atrial arrhythmias. After induction of anesthesia, we exsected the heart and isolated the atria of 48 male Wistar rats. Later, we recorded the beating and contractile force of the atria by a physiograph. Subsequently, we studied the effects of diazoxide [2 to 100 micro g/mL] on beating and contractile force of the isolated atria 5, 10, 15 and 20 minutes after applying the drug onto the atria. Diazoxide administration [2 to 100 micro g/mL] showed a significant decrease [7% to 49% depending on concentration] in atrial beatings [P

BCL-2 and bax expression in skin flaps treated with finasteride or azelaic acid

Despite all modern surgical techniques, skin flap that is considered as the main method in most reconstructive surgeries puts the skin tissue at danger of necrosis and apoptosis derived from ischemia. Therefore, finding a treatment for decreasing the apoptosis derived from flap ischemia will be useful in clinic. In present study, we evaluated the effect of azelaic acid 20% and finasteride on expression of BCL-2 and bax proteins after the skin flap surgery. For this purpose, 21 rats were entered in three groups including control, azelaic acid 20% and finasteride, all experienced skin flap surgery and then flap tissue was assessed for determining the expression of proteins in 5 slices prepared from each rat that were graded between - to +++ scales. Both azelaic acid and finasteride increased the expression of BCL-2 protein [p < 0.05] and decrease the expression of bax protein [p < 0.05]. These results suggested an antiapoptotic role for finasteride and azelaic acid in preserving the flap after the ischemia reperfusion insult

Nitric oxide is necessary for diazoxide protection against ischemic injury in skeletal muscle

Ischemia reperfusion injury [IR injury] is a common problem in clinical conditions. Researches have frequently revealed that ATP- sensitive potassium [K[ATP]] channels and nitric oxide plays a role in protection against ischemic injury in skeletal muscle. The present study aimed at evaluating the possible link between this two pathways. Sixty-eight male wistar rats, were pretreated with saline, diazoxide [K[ATP] opener; 45 mg/Kg, IP], glibenclamide [K[ATP] inhibitor; 5 mg/Kg], or L-NAME [iNOS inhibitor; 20 mg/Kg, IP] before 3 h ischemia and 2 h reperfusion. Activities of antioxidant enzymes superoxide dismutase [SOD] and catalase [CAT], and the level of malondialdehyde [MDA] and expression of iNOS were measured in muscle tissue. Tissue MDA content was significantly increased by IR [p < 0.001]. Diazoxide significantly decreased the IR-induced elevation of tissue MDA level [p < 0.05] and Glibenclamide increased MDA [p < 0.05 vs. IR group]. L-NAME inhibited the effect of diazoxide on decreasing MDA [p < 0.01 vs., diazoxide+IR group] and IR decreased the activity of SOD and CAT [p < 0.01], while pretreatment with diazoxide increased activity of SOD and CAT [p < 0.01]. Glibenclamide decreased SOD and CAT activity after IR [p < 0.05]. L-NAME pretreatment in diazoxide-treated rats abolished the effect of diazoxide on increasing the activity of SOD and CAT [p < 0.05 vs. Diaz+IR]. Expression of iNOS was increased by IR [p < 0.01 vs. Sham group]. Diazoxide significantly decreased iNOS expression after IR [p < 0.05 vs. IR]. L-NAME significantly decreased iNOS expression after IR [p < 0.01] in diazoxide-treated rats [p < 0.01 vs. Diaz+IR]

Effect of short and long-term treatment with omega-3 fatty acids on scopolamine-induced amnesia

Two omega-3 fatty acids including docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA] are essential for the physiologic function of neuronal cell membrane. Normal function of neuronal cell membrane requires appropriate composition of fatty in its structure. Present study was designed to compare the effect of short-term and long-term pretreatment with omega-3 fatty acids on scopolamine-induced amnesia and possible involvement of apoptotic or oxidative pathways. Male Wistar rats were gavaged by omega-3 fatty acids [60 mg/Kg [DHA + EPA]] or saline for 2 weeks [short-term model] or 8 weeks [Long-term model], then received intra-CA1 scopolamine [2 mg/rat]. Finally, the avoidance response was examined and hippocampus tissue was prepared. Intra-CA1 injection of scopolamine abolished the memory performance in rats. Short-term or long-term pretreatment with omega-3 fatty acids improved memory [p < 0.01 and p < 0.001, respectively]. Pretreatment for 2 weeks had no effect on the tissue Malondialdehyde [MDA] contents or SOD and CAT activity. In addition, pretreatment for 2 weeks with omega-3 fatty acids had no effects on tissue Bax and Bcl-2 expression. Conversely, long-term pretreatment with omega-3 fatty acids decreased tissue MDA contents [p < 0.01], SOD activity [p < 0.05] and increased CAT activity [p < 0.01]. Long-term pretreatment with omega-3 fatty acids also decreased Bax protein expression [p < 0.05] with no effect on the expression of Bcl-2 protein. In conclusion, long-term exposure to omega-3 fatty acids inhibited the scopolamine-induced oxidative stress, apoptosis and amnesia while the effect of short-term treatment was restricted to the improved memory without significant effect on apoptosis or oxidative stress. Therefore, long-term treatment with low doses of omega-3 fatty acids suggested a suitable treatment for amnesia

mechanism of preventive effect of captopril on renal ischemia reperfusion injury is independent of ATP dependent potassium channels

Renal ischemia reperfusion [IR] injury has been a major source of concern during the past decades and angiotensin converting enzyme [ACE] inhibitors have been successfully used to prevent this injury. There have been some controversial reports about the involvement of KATP channels in the mechanism of action of ACE inhibitors. In this study, we examined the effect of KATP channel blocker [Glibenclamide] on preventive effect of captopril on renal IR injury. Male sprauge-dawley rats were pretreated with glibenclamide [1, 5 and 25 mg/kg] and/or captopril [5 mg/kg]. They were anesthetized using ketamine [50 mg/kg] and xylazine [10 mg/kg]. The left flank was incised and the left renal artery was clamped for 30 minutes. After that, the kidney was reperfused for 2 hours and then the animal was killed. The Right and left kidneys were removed and evaluated for microscopic damage. Captopril reduced renal IR injury while glibenclamide by itself caused no change. Glibenclamide did not change the preventive effect of captopril. It seems that the preventive effect of captopril is not directly mediated by KATP channels and further attention should be paid to other receptor-mediated angiotensin II effects

[ comparison between the efficacy of intralesional injection of 2% Zinc Sulfate solution with Glucantime in the treatment of acute old world cutaneous Leishmaniasis: a randomized, double-blind, controlled clinical trial]

Several treatment modalities have been used for cutaneous leishmaniasis[CL] with various results. In vitro and in vivo studies have shown inhibitory effects of zinc sulfate [ZnSO4] on Leishmania parasites. To compare the efficacy of intralesional injections of 2% ZnSO4 solution with meglumineantimonate[Glucantime] in the treatment of acute Old World CL. Seventy-two patients with CL with a duration of less than 8 weeks were recruited in a randomized, double-blind, clinical trial in Isfahan province - an area endemic for Leishmania major - after giving written informed consent. They were treated with 6 weekly intralesional injections of either 2% sterile ZnSO4 solution or Glucantime prepared in identical vials. The primary outcome measure was complete re-epithelialization of CL lesions. Among 36 patients with 53 lesions treated with ZnSO4 and 36 patients with 53 lesions treated with Glucantime, 13 patients with 19 lesions and 22 patients with 31 lesions completed the trial, respectively. Inadequacy of treatment was the main reason for drop-out in 12 [33.3%] and 2 [5.5%] patients in ZnSO4 and Glucantime groups, respectively [P < 0.05]. Complete re-epithelialization was observed in 2 [10.5%] and 19 [61.3%] lesions 1 week after the end of treatment in the ZnSO4 and Glucantime groups, respectively [P < 0.05]. A six-week course of weekly intralesional injections of 2% ZnSO4 solution was less effective than Glucantime in the treatment of acute Old World CL