The protective effect of taurine on cyclophosphamide-induced testicular toxicity in rats.

This study aimed to evaluate the protective effect of taurine (TAU) with regard to antioxidant, anti inflammatory and antiapoptotic pathways on cyclophosphamide (CP)-induced testicular toxicity in rats. Forty Sprague-Dawley male rats were used in this experimental study. The CP group animals received a single dose of 200mg/kg CP on Day 8 intraperitoneally (i.p). The other groups were treated with TAU (75, 150 and 300mg/kg) orally for 14 days prior to and following a single i.p injection of CP. Morphometrical analysis and histological examination of testicular tissue were performed. Serum testosterone, LH and FSH levels were measured in serum using commercial ELISA kits. The testicular injury induced by CP was evaluated in terms of oxidative stress, inflammation and apoptosis with a significant inflammatory and apoptotic response and an insignificant oxidative stress. TAU treatment resulted in improvement in body weight gain, oxidative stress, inflammation and apoptosis, some of which were significant. The improvement was more pronounced for antiapoptotic effect of taurine in the testis of CP-treated animals. It was concluded that TAU may prevent and/or treat the testicular toxicity by ameloirating oxidative stress, inflammation and apoptosis.

Chlorogenic acid co-administration alleviates cisplatin-induced peripheral neuropathy in rats.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is still an unresolved problem in cisplatin (CIS) use. OBJECTIVES: This study investigates possible anti-neuropathic effect of chlorogenic acid (CGA) against CIS-induced CIPN in rats while also investigating the contribution of nitric oxide (NO) to this phenomenon. METHODS: Initially, CGA (250-1000 µM) was tested by MTT assay on primary DRG neurons. Subsequently, CIPN was induced in Sprague-Dawley rats by 3 mg/kg intraperitoneal injections of CIS once/week for 5 weeks. CGA (100 mg/kg) was co-administered with CIS, both alone and in combination with l-arginine (LARG) or l-nitro-arginine-methyl-ester (LNAME), to elucidate the contribution of nitrergic system to anti-neuropathic effects. Mechanical allodynia, thermal hyperalgesia, and cold plate tests were performed to test CIPN. Rotarod, footprint analysis, and activitymeter were used to evaluate motor coordination and performance. Tumor necrosis factor alpha (TNF-α) was measured as a marker of inflammation. Histological evaluations of DRG and sciatic nerves (SNs) were performed utilizing toluidine blue staining. Two-way analysis of variance and Kruskal-Wallis following Tukey's test were used as statistical analysis. RESULTS: Higher concentration of CGA (1000 µM) exhibited protective effect against in vitro neurotoxicity. Neither LARG nor LNAME exerted significant change in this effect. Co-administration of CGA alleviated histological abnormalities and neuropathic effects induced by CIS. Ameliorative effect of CGA was not changed in mechanical allodynia but attenuated in cold allodynia, and motor activity/coordination tests by LARG and LNAME. Neuropathic effects of CIS remained unchanged with LARG and LNAME in behavioral experiments. CONCLUSION: The study identified CGA as candidate agent in mitigating CIPN. NO seems to play a modulatory role in this effect.

Dose-Dependent Effect of Hydrogen Sulfide in Cyclophosphamide-Induced Hepatotoxicity in Rats.

BACKGROUND: Cyclophosphamide is a commonly used anticancer and immunosuppressive agent; however, hepatotoxicity is one of its severe toxicities. Hydrogen sulfide is a gaseous signaling molecule that plays crucial regulatory roles in various physiological functions. This study aimed to evaluate the hepatoprotective effect of hydrogen sulfide against cyclo phosp hamid e-ind uced hepatic damage in rats. METHODS: Hepatotoxicity was induced by the single intraperitoneal administration of cyclophosphamide (200 mg/kg). Sprague-Dawley rats were treated by hydrogen sulfide donor, sodium hydrosulfide (25, 50, and 100 µmol/kg, intraperitoneal) 7 days before and 7 days after the administration of a single intraperitoneal injection of cyclophosphamide (200 mg/kg). Cyclo phosp hamide-ind uced hepatotoxicity was evaluated by serum and tissue biochemical and histopathological assessments. The levels of hydrogen sulfide, nitric oxide, cyclic guanosine monophosphate, interleukin 6, and interleukin 10 in liver homogenates were also determined by ELISA. One-way analysis of variance and Kruskal-Wallis tests were used as statistical analyses. RESULTS: Cyclophosphamide increased liver function enzymes (alanine aminotransferase and aspartate aminotransferase), immunoreactivity to caspase-3 and Apaf-1, and proinflammatory cytokines. Cyclophosphamide also induced histopathological alterations including pycnotic nucleus with eosinophilic cytoplasm, increased sinusoidal dilatation, congestion, and edema. Hydrogen sulfide cotreatment significantly reduced cyclo phosp hamid e-ind uced inflammation, histological alterations, and apoptosis in the liver. 50 mg/kg sodium hydrosulfide was more effective against cyclo phosp hamid e-ind uced hepatotoxicity. CONCLUSION: In conclusion, hydrogen sulfide with its anti-inflammatory and anti-apoptotic effects seems to be beneficial as an adjunct to cyclophosphamide treatment to reduce cyclo phosp hamid e-ind uced hepatotoxicity and thereby can be suggested as a promising agent to increase the therapeutic efficacy of cyclophosphamide.

The effect of fucoidin on kidney and lung injury in a rat infrarenal aortic ischemia-reperfusion model.

BACKGROUND: The aim of this study was to investigate the effects of fucoidin on rat kidney and lung in an infraaortic ishemia reperfusion model. METHODS: Forty Wistar rats were randomly divided into five groups (n = 8) as sham, control (IR), before ischemia (BI), before reperfusion (BR), and before ischemia and before reperfusion (BI/BR). Rats were subjected to 120 minutes ischemia followed by 120 minutes reperfusion with application of infrarenal aortic clamping. BI received intravenous fucoidin (25 mg/kg) ten minutes before establishing ischemia and BR received ten minutes before reperfusion. BI/BR group received half equal doses of fucoidin both before ischemia (12.5 mg/kg) and reperfusion (12.5 mg/kg) periods, respectively. After sacrification blood and tissue samples were obtained for biochemical (Malondialdehyde (MDA), Nitric oxide (NO), Myeloperoxidase (MPO), Catalase (CAT), Plasma Chitotriosidase (CHIT) and serum ischemia modified albumin (IMA)) and histologic examinations. RESULTS: MDA, NO, MPO, CAT, and IMA levels were lower in BR and BI/BR groups compared to control group (p < 0.001). Plasma CHIT levels in BR and BI/BR groups were lower than in control group (p < 0.05). According to histological examination kidney and lung injury scores were lower in BR and BI/BR groups compared to control group (p < 0.01 and p < 0.001, respectively). CONCLUSION: The study showed that fucoidin is effective in preventing kidney and lung injury if administered before reperfusion or both before ischemia and reperfusion. However, it has no effect if administered only before ischemia.

2-Aminoethoxydiphenyl borate ameliorates functional and structural abnormalities in cisplatin-induced peripheral neuropathy.

AIM OF THE STUDY: Cisplatin is a platinum-derived chemotherapeutic agent commonly used in the treatment of various tumors. Ototoxicity, nephrotoxicity, and peripheral neuropathy are the most common side effects of this drug. 2-Aminoethoxydiphenyl borate (2-APB), boron- containing compound, has some protective effects against various tissue damage. The present study aimed to investigate the potential protective effects of 2-APB on in vitro and in vivo cisplatin-induced neurotoxicity. MATERIALS AND METHODS: MTT assay was used to determine cell viability in DRG cells. Peripheral neuropathy was induced in forty male Sprague-Dawley rats (200-250g) by administering cisplatin (3 mg/kg/week) intraperitoneally (i.p) for five weeks. 2-APB (2, 4, and 8 mg/kg, i.p) was administered. Mechanical allodynia, thermal hyperalgesia, cold allodynia, mechanical stimuli, motor coordination, and locomotor activity tests were performed. DRG cells and sciatic nerves were analyzed histologically. NGF, BDNF, TNF-α, GSH, MDA, and LDH levels were investigated in rat DRG tissue homogenates. RESULTS: Our results revealed that 2-APB ameliorated cisplatin-induced neurotoxicity by improving mechanical and cold allodynia and motor coordination impairment. It also reduced cisplatin-induced structural toxicity in peripheral tissues. CONCLUSION: These findings demonstrated that 2-APB could be considered as a potential therapeutic strategy for the treatment of cisplatin-induced peripheral neuropathy.

Research Into the Effect of Proton Pump Inhibitors on Lungs and Leukocytes.

BACKGROUND: Proton pump inhibitors (PPI) are the most commonly used medication in the world. They are prescribed as an effective treatment choice for gastrointestinal system diseases linked to hyperacidity, especially. Additionally, non-indication and unnecessary use are very common. Many publications in recent times have reported significant side effects. However, there are insufficient studies about the mechanism for these side effects. METHODS: Twenty-four Wistar albino rats were used in this study. Rats were divided into 3 groups of control, group-administered H2 receptor blockers and a group-administered PPI. Medications were administered for 30 days intraperitoneal. After 30 days, rats were euthanized and lung tissue was obtained. Lung was stained for immunohistochemical catalase, superoxide dismutase, Glutathione peroxidase, myeloperoxidase, and toluidine blue and investigated with a light microscope. Transmission electron microscopy (TEM) was used to investigate lung tissues and neutrophil leukocytes. Additionally, lung tissue had biochemical hydrogen peroxide (H2O2) levels researched. RESULTS: H2O2 amounts, produced by lysosomes with important duties for neutrophil functions in lung tissues, were found to be statistically significantly reduced in the group-administered PPI. Results from investigations of specimens obtained with immunohistochemical staining observed increases in antioxidant amounts in the PPI group. Investigation with TEM identified more inflammation findings in the lung tissue from the group-administered PPI compared to the control group and the group-administered H2 receptors. CONCLUSION: In conclusion, we identified long-term PPI use disrupts neutrophil leukocyte functions in the lung. All clinicians should be much more careful about PPI use.

Cisplatin decreases HOXA13 and alphaVBeta3 integrin levels in the uterus.

OBJECTIVE: To examine the effects of cisplatin on uterine histology and implantation molecules and the possible protective role of recombinant Klotho administration on uterine histology and uterine receptivity in mice exposed to cisplatin. MATERIALS AND METHODS: This study was conducted using thirty-two adult female mice assigned to four groups with 8 mice in each group. Saline was given to the 1st group, cisplatin to the 2nd group, recombinant mouse Klotho to the 3rd group and recombinant mouse Klotho plus cisplatin to the 4th group. Uterine tissues were examined for damage histologically and immunobiologically for the uterine receptivity markers HOXA13 and alphaVBeta3 integrin. RESULTS: Apoptosis, degeneration, decrease in uterine thickness and uterine absence of gland scores were higher in the cisplatin group (3rd group) compared to the saline group (1st group) (cisplatin vs. saline p < 0.0001 for all parameters). In the recombinant Klotho plus cisplatin group (4th group), scores of apoptosis, degeneration, reduction in uterine thickness and uterine absence of gland were lower than the group receiving only cisplatin (cisplatin plus recombinant Klotho vs cisplatin, p = 0.006 for apoptosis; p = 0.017 for degeneration; p = 0.011 for the reduction in uterine thickness; p = 0.002 for the absence of gland). However, HOXA13 and alphaVBeta3 integrin staining levels were not different between the cisplatin group (group 3) and the cisplatin plus recombinant Klotho group (group 4) (p = 0.980 and p = 0.762, respectively.) CONCLUSION: Cisplatin has adverse effects on the uterus. Administration of recombinant Klotho was found to attenuate the cisplatin-induced damage but failed to preserve levels of the implantation molecules HOXA13 and alphaVbeta3. Further studies examining the effect of cisplatin toxicity using other implantation markers along with functional studies are needed.

Protective effects of anandamide against cisplatin-induced peripheral neuropathy in rats

Background/aim: Cisplatin (CIS) is an effective antineoplastic agent used in the treatment of several cancer types. Peripheral neuropathy is a major dose-limiting side-effect in CIS therapy. Cannabinoids may alleviate this painful side effect. This study investigated the analgesic effects of anandamide (AN) on CIS-induced peripheral neuropathy, in vitro effects of AN in CIS neurotoxicity, and the contribution of nitric oxide (NO) in this effect. Materials and methods: This is an experimental animal study. Primary dorsal root ganglion (DRG) cultures were prepared from one-day-old rats for in vitro investigations. DRG cells were incubated with CIS (100­300 M), and AN (10, 50, 100, and 500 µM) was administered with the submaximal concentration of CIS. Female Sprague Dawley rats were divided into control, CIS, CIS+AN, CIS+AN+L-NG-nitro arginine methyl ester (LNAME). CIS was administered 3 mg/kg i.p once weekly for 5 weeks. AN (1 mg/kg i.p) or in combination with 10 mg/kg i.p LNAME was administrated 30 min before CIS injection. Mechanical allodynia, thermal hyperalgesia, and tail clip tests were performed. After intracardiac perfusion, sciatic nerves (SN), and DRGs were isolated and semi-thin sections were stained with toluidine blue and investigated histologically. SPSS v. 21.0 and Sigma STAT 3.5 were used for statistical analysis. One/two way ANOVA, Kruskal­Wallis, and Wilcoxon signed ranks tests were used. A p-value of 0.05 was accepted as significant. Results: CIS caused significant mechanical allodynia. AN and AN+LNAME significantly increased hind paw withdrawal latency in mechanical allodynia test. The degenerated axons significantly increased in CIS group, while decreased in AN group. The frequency of larger neurons seemed to be higher in CIS+AN group. Conclusion: AN may be a therapeutic alternative for the treatment of CIS-induced peripheral neuropathy. However, its central adverse effects must be considered.

Protective and therapeutic effect of hydrogen sulfide on hemorrhagic cystitis and testis dysfunction induced with cyclophosphamide

Backround/aim: Cyclophosphamide (CP) is a drug used for treatment of many malignant diseases. However, it can cause serious side effects such as hemorrhagic cystitis and male infertility. Hydrogen sulfide (H2S) is a gaseous mediator and is suggested to have antioxidant, antiinflammatory, and antiapoptotic effects. In this study, dose-dependent effects of H2S donor sodium hydrosulfide (NaHS) on cyclophosphamide-induced hemorrhagic cystitis and testicular dysfunction were investigated in rats. Material and methods: Rats were divided into 5 groups (n = 8): control, CP, NaHS25 µmol/kg, NaHS50 µmol/kg, and NaHS100 µmol/ kg. After treatment for 7 days intraperitoneally (ip), a single ip dose of CP 200 mg/kg was given on the 8th day. Then, treatment was continued for 7 days. In bladder and testicular tissues, IL 6, IL 10, cGMP, NO, H2S, FSH, LH, and testosterone levels were measured by ELISA. Histopathological examination with H&E staining, as well as immunohistochemical staining for acrolein in bladder and caspase-3 and APAF-1 in testis were performed. Results: NaHS prevented the increased IL 6 and IL 10 values induced by CP as well as prevented the decrease in cGMP values associated with CP. There was no significant change in FSH values, but the LH value, which increased with CP, decreased with 25, 50, and 100 µmol/kg NaHS. In contrast, testosterone decreased in the CP group and increased in the treatment groups. NaHS was effective in many biochemical and histopathological parameters at 25 and 50 µmol/kg doses, and this effect decreased at 100 µmol/kg dose. Conclusion: H2S has a protective and therapeutic effect on hemorrhagic cystitis and testicular dysfunction induced by cyclophosphamide. It can be suggested that H2S is a promising molecule in facilitating cancer treatment.

The effects of recombinant klotho in cisplatin-induced ovarian failure in mice.

AIM: To investigate whether recombinant klotho given concomitantly with cisplatin is effective in preventing cisplatin-induced ovarian damage. METHODS: Thirty-two adult female mice were divided into four groups. Saline was given to the first group, cisplatin to the second group, recombinant mouse klotho to the third group, and recombinant mouse klotho + cisplatin to the fourth group. The removed ovarian tissues were examined and groups were compared histologically and immunohistochemical examination for antimullerian hormone (AMH), superoxide dismutase (SOD) and catalase expression were done. Glutathione peroxidase (GPx) and glutathione reductase (GR) activities were measured by ELISA. RESULTS: Ovarian tissue weight, primary and secondary follicle counts were higher in cisplatin + recombinant klotho group compared to cisplatin group in our study (respectively p < 0.0001, p < 0.0001, and p = 0.010). Injury scores (stromal congestion, edema and infiltration, follicular degeneration scores and edema in corpus luteum scores) were similar between cisplatin and cisplatin + recombinant klotho groups (all p > 0.05). AMH staining intensities were similar between cisplatin and cisplatin + recombinant klotho groups (p = 0.925). There was no difference between the groups in terms of SOD, GPx, and GR (p > 0.05). CONCLUSIONS: The recombinant klotho administered before cisplatin could partially protect the ovarian tissue from cisplatin-induced ovarian damage considering that there was no difference in histologic injury score parameters, AMH staining intensity and oxidative stress markers between cisplatin and cisplatin plus klotho groups except that klotho preserved follicules to some extent. The antioxidant mechanism of action of klotho may not be the primary protection mechanism in cisplatin induced ovarian injury.

Antenatal pentoxifylline therapy to prevent endotoxin-induced fetal injury in the preterm goat model.

OBJECTIVE: Pentoxifylline (PTX) has immunomodulatory properties and is known to reduce sepsis-associated infant mortality. We aimed to evaluate maternal oral and intra-amniotic administration of PTX for the prevention of fetal inflammation and injury in a caprine model. MATERIALS AND METHODS: Inflammation-mediated fetal injury was induced with maternal granulocyte-colony stimulating factor and intra-amniotic endotoxin at 0.76 of gestation in date-mated pregnant goats. Eight groups were formed (n=4 each): Control, fetal injury, oral 30 mg/kg/day and 60 mg/kg/day PTX for 15 days + fetal injury, intra-amniotic 400 mg/kg and 800 mg/kg estimated fetal weight single-dose PTX with and without fetal injury. Preterm delivery by hysterotomy was performed at 0.80 of gestation to evaluate the fetal and placental effects. Immunochemistry for various markers including interleukins, caspases, cyclooxygenases, vimentin, myelin basic protein, and surfactant proteins were carried out in the fetal lungs, fetal brain, and placenta. Fetal plasma and amniotic fluid interleukins were also evaluated. Kruskal-Wallis H test and Mann-Whitney U test were used for comparisons. RESULTS: High-dose (60 mg/kg/day) maternal prophylactic oral treatment attenuated endotoxin-related histological injury and was related to low inflammatory marker expressions comparable to the controls (p>0.05 except cyclooxygenase 2). Following maternal oral administration, fetal plasma and amniotic fluid levels of the studied interleukins were also lower than the untreated endotoxin-exposed animals (p<0.05 for all comparisons). Intra-amniotic PTX was associated with inconsistent results and increased inflammatory markers in some fetuses. CONCLUSION: Oral PTX before preterm birth mitigates intrauterine inflammation with neuroprotective effects in the fetus. PTX can be considered as a candidate drug for fetal brain injury prevention in the preterm period.

Do Resveratrol and Dehydroepiandrosterone Increase Diminished Ovarian Reserve?

OBJECTIVE: In this study, the aim is to observe changes induced by dehydroepiandrosterone (DHEA) and resveratrol (RES) in diminished ovarian follicles that was induced by 4-vinylcyclohexenediepoxide (VCD). MATERIALS AND METHODS: Twenty four Wistar albino female rats were divided into 3 groups: control, DHEA and RES. Unilateral oophorectomy was performed in control group to remove the right ovary of 4 rats and the left ovary of 4 rats. After administration of 160 mg/kg VCD, remaining ovaries were removed. Following the same VCD treatment, in DHEA and RES groups, 60 mg/kg DHEA and 20 mg/kg RES were given for 45 days respectively and residual ovaries were removed. Hematoxylin-eosin and TUNEL staining were performed. Follicle stimulating hormone (FSH), estradiol (E2) and anti-mullerian hormone (AMH) values were measured. RESULTS: In control group, VCD-induced apoptosis in follicles increased the TUNEL-positive cell counts (p<0.001) with decreased number of follicles. On the other hand, DHEA significantly increased all three follicle types in the ovaries and decreased apoptosis (p<0.001). The decreased follicle number in all three follicle types after VCD treatment were found to be significantly increased after RES treatment (p<0.001). Apoptosis in the follicles was significantly decreased by RES administration (p<0.001). FSH values were found to be increased with VCD and to reach control values with DHEA and RES. E2 values significantly decreased with VCD, but significantly increased with RES and DHEA. CONCLUSION: Both DHEA and RES may improve VCD-induced diminished ovarian reserve. DHEA and RES increased the number of primary, primordial and growing follicles, with no significant difference between them.

Evaluation of wound healing effect of chitosan-based gel formulation containing vitexin.

Acute or chronic wounds are one of the most common health problems worldwide and medicinal drugs or traditional remedies are often used in wound healing. Further studies regarding wound treatment are rapidly continuing. Vitexin is a phenolic compound, which is found in many medicinal plants, has different pharmacological effects such as anti-inflammatory, analgesic and antioxidant. In the present study, it is aimed to investigate the wound healing effect of formulation prepared as chitosan-based gel with vitexin in vivo and in vitro. Cytotoxicity and wound healing assays were used for in vitro and excisional wound model is used for in vivo studies. Extracted tissues from wound area were histologically examined. Wound healing process was monitored on 7, 14 and 21st days. When wound construction was evaluated, chitosan-based gel formulation containing vitexin demonstrated significant effect compared to control group. Histological examinations demonstrated that skin regeneration was promoted by vitexin formulation. Significant cell proliferation was observed with vitexin/chitosan dispersion in the wound healing assay performed with NIH 3T3 and HaCaT cells. In conclusion, our test substance chitosan-based gel formulation containing vitexin significantly accelerated wound healing both in vivo and in vitro.

The therapeutic potential of amifostine on cyclophosphamide-induced testicular dysfunction in rats: An experimental study.

BACKGROUND: Cyclophosphamide (CP) is a well-known alkylating anticancer agent used in the treatment of various malignant and non-malignant tumors. CP may also cause a variety of adverse effects, including reproductive toxicity. Amifostine is known as a cytoprotective drug having antioxidant properties. OBJECTIVE: To evaluate the possible beneficial effects of amifostine on testicular toxicity induced by CP in rats. MATERIALS AND METHODS: A total of 35 Sprague-Dawley rats were used in this experimental study. The CP group animals received a single dose of 200 mg/kg CP on Day 8 by intraperitoneal injection and were left untreated for the following seven days. The two remaining groups of animals were treated with 200 mg/kg/day amifostine (AMF 200) and 400 mg/kg/day amifostine (AMF 400) for seven days prior to and following a single intraperitoneal injection of CP. Morphometrical analysis and histological examination of testicular tissue were performed. Serum testosterone, luteinizing hormone, and follicle-stimulating hormone levels were measured in serum using commercial ELISA kits. The epidydimal sperm count was determined. RESULTS: The tubular epithelial height in the testis was significantly higher in the AMF400 group compared to other groups (p < 0.001). Animals in the AMF400 group showed minimal debris in the tubules, no Sertoli cell damage, and the Johnsen scores were slightly higher in the AMF400 group. The epididymal sperm count was significantly lower in the CP-administered animals compared to the control animals and was significantly higher in the AMF200 and AMF400 groups compared to the CP group (p = 0.006, and p = 0.019 respectively). CONCLUSION: Amifostine, at a dose of 400 mg/kg, may have a protective effect on testicular damage induced by CP in rats.

Inflammation-mediated fetal injury by maternal granulocyte-colony stimulating factor and high-dose intraamniotic endotoxin in the caprine model.

OBJECTIVE: To define a novel experimental model with maternal intravenous (i.v.) granulocyte-colony stimulating factor (G-CSF) followed by a single- and high-dose of 20 mg intra-amniotic (IA) endotoxin to induce fetal brain injury in the preterm fetal goat. MATERIALS AND METHODS: Pregnant goats (n=4) were given 50 microg/day G-CSF into the maternal jugular vein through gestational days 110-115 (term, 150 days). At gestational day 115, 20 mg of IA endotoxin was administered. Following preterm delivery at day 120 by cesarean section umbilical cord, fetal lung and brain tissues were harvested for histopathology, immunohistochemistry, and electron microscopy. Inflammatory markers were evaluated in the amniotic fluid and fetal plasma. RESULTS: Necrotizing funisitis with abundant leukocyte infiltration and fetal brain injury was induced in all the fetuses in the experimental group. CONCLUSION: Maternal i.v. G-CSF for 5 days followed by 20 mg of IA endotoxin is a feasible caprine model to exacerbate intrauterine inflammation.

Bone Marrow Mesenchymal Stem Cell Transplantation Enhances Nerve Regeneration in a Rat Model of Hindlimb Replantation.

BACKGROUND: Successful limb replantation must be based not only on the viability of the amputated part but also on satisfactory long-term functional recovery. Once the vascular, skeletal, and soft-tissue problems have been taken care of, nerve recovery becomes the ultimate limiting factor. Unfortunately, nerve regeneration after limb replantation is impaired by several consequences. The authors tested the hypothesis that bone marrow mesenchymal stem cells could improve nerve regeneration outcomes in an experimental model of limb replantation. METHODS: Twenty rats underwent replantation after total hindlimb amputation. Animals were subdivided into two groups: a replanted but nontreated control group and a replanted and bone marrow mesenchymal stem cell-transplanted group. Three months after surgery, nerve regeneration was assessed using functional, electrophysiologic, histomorphologic, and immunohistochemical analyses. RESULTS: Bone marrow mesenchymal stem cell-treated animals showed significantly better sciatic functional index levels and higher compound muscle action potential amplitudes in comparison with the controls. Histomorphometric analysis revealed that the number of regenerating axons was approximately two-fold greater in the treated nerves. In addition, the mean g-ratio of these axons was within the optimal range. Immunohistochemical assessment revealed that expression of S-100 and myelin basic protein in the treated nerves was significantly higher than in controls. Correspondingly, the expression levels of anti-protein gene product 9.5 and vesicular acetylcholine transporter in motor endplates were also significantly higher. Finally, muscles in the bone marrow mesenchymal stem cell-transplanted group showed significantly larger average fiber areas. CONCLUSION: The authors' findings demonstrate that it is possible to improve the degree of nerve regeneration after limb replantation by bone marrow mesenchymal stem cell transplantation.

Effects of hydrogen sulfide on acetaminophen-induced acute renal toxicity in rats.

INTRODUCTION AND AIM: Hydrogen sulfide (H2S) is an endogenously produced gas-structure mediator. It is proposed to have antioxidant, anti-inflammatory and antiapoptotic effects. Acetaminophen (N-acetyl-P-aminophenol; APAP) is an antipyretic and analgesic medication known as paracetamol. When taken at therapeutic doses there are few side-effects, but at high doses APAP can cause clear liver and kidney damage in humans and experimental animals. In this study, the effects of the H2S donor of sodium hydrosulfide (NaHS) on acute renal toxicity induced by APAP in rats were researched in comparison with N-acetyl cysteine (NAC). METHOD: Rats were divided into six groups (n = 7) as control. APAP, APAP + NAC, APAP + NaHS 25 µmol/kg, NaHS 50 µmol/kg and NaHS 100 µmol/kg. After oral dose of 2 g/kg APAP, NAC and NaHS were administered via the i.p. route for 7 days. In renal homogenates, KIM-1 (Kidney Injury Molecule-1), NGAL (neutrophil gelatinase-associated lipocalin), TNF-α and TGFß levels were measured with the ELISA method for tissue injury and inflammation. In renal tissue, oxidative stress levels were identified by spectrophotometric measurement of TAS and TOS. Histopathologic investigation of renal tissue used caspase 3 staining for apoptotic changes, Masson trichrome and H&E staining for variations occurring in glomerular and tubular systems. RESULTS: NaHS lowered KIM-1, NGAL, TNF-α, TGF-ß and TOS levels elevated in renal tissue linked to APAP and increased TAS values. NaHS prevented apoptosis in the kidney and was identified to ensure histologic amelioration in glomerular and tubular structures. NaHS at 50 µmol/kg dose was more effective, with the effect reduced with 100 µmol/kg dose. CONCLUSION: H2S shows protective effect against acute renal injury linked to APAP. This protective effect reduces with high doses of H2S. The anti-inflammatory and antioxidant activity of H2S may play a role in the renoprotective effect.

Comparative Analysis of Mesenchymal Stem Cells from Bone Marrow, Adipose Tissue, and Dental Pulp as Sources of Cell Therapy for Zone of Stasis Burns.

Introduction: The implantation of mesenchymal stem cells (MSCs) has been shown to exert benefits for the survival of the zone-of-stasis. However, the clinical experience indicates the importance of selecting the right source and type of stem cells. Therefore, we planned the current study to perform a quantitative comparison of MSCs isolated from three different sources to provide information useful in selection of the optimal source and to see whether critical mechanisms are conserved between different populations. Methods: The protective effects of MSCs derived from bone marrow, adipose tissue and dental pulp were compared in a rat model of thermal trauma. The stasis zones were evaluated 72 h after the burn using histochemistry, immunohistochemistry and biochemistry. Results: Gross evaluation of burn wounds revealed that the differences between the mean percentages of the calculated necrotic areas weren't statistically significant. Semi-quantitative grading of the histopathological findings revealed that there were no significant differences between damage scores. Immunohistochemical assessment of apoptotic and necrotic cell deaths revealed that the differences between the mean numbers of apoptotic and necrotic cells weren't statistically significant. Myeloperoxidase activity was found to be significantly lower in the adipose tissue group. Biochemical and immunohistochemical assessment of tissue malondialdehyde revealed that the differences between the groups weren't statistically significant. Finally, the number of neo-vessels in the dental pulp group was found to be significantly higher. Conclusion: Our findings suggest that bone marrow, adipose tissue and dental pulp may serve as a universal donor MSC source for the prevention of burn wound progression.

Prevention of Burn Wound Progression by Mesenchymal Stem Cell Transplantation: Deeper Insights Into Underlying Mechanisms.

INTRODUCTION: Burns are dynamic wounds that may present a progressive expansion of necrosis into the initially viable zone of stasis. Therefore, salvage of this zone is a major subject of focus in burn research. The beneficial effects of mesenchymal stem cells (MSCs) on the survival of the zone of stasis have been previously documented. However, many gaps still exist in our knowledge regarding the underlying protective mechanisms. Hence, this study was designed to evaluate the pathophysiological basis of MSCs in the prevention of burn wound progression. METHODS: Wistar rats received thermal trauma on the back according to the "comb burn" model. Animals were randomly divided into sham, control, and stem cell groups with sacrifice and analysis at 72 hours after the burn. The stasis zones were evaluated using histochemistry, immunohistochemistry, biochemistry, real-time polymerase chain reaction assay, and scintigraphy to evaluate the underlying mechanisms. RESULTS: Gross evaluation of burn wounds revealed that vital tissue percentage of the zone of stasis was significantly higher in the stem cell group. Semiquantitative grading of the histopathologic findings showed that MSCs alleviated burn-induced histomorphological alterations in the zone of stasis. According to CC3a staining and expression analysis of Bax (B-cell leukemia 2-associated X) and Bcl-2 (B-cell leukemia 2) genes, MSCs attenuated increases in apoptosis postburn. In addition, these transplants showed an immunomodulatory effect that involves reduced neutrophilic infiltration, down-regulation of proinflammatory cytokines (tumor necrosis factor α, interleukin 1ß [IL-1ß], and IL-6), and up-regulation of the anti-inflammatory cytokine IL-10 in the zone of stasis. Burn-induced oxidative stress was significantly relieved with MSCs, as shown by increased levels of malondialdehyde, whereas the expression and activity of the antioxidant enzyme superoxide dismutase were increased. Finally, MSC-treated interspaces had enhanced vascular density with higher expression levels for vascular endothelial growth factor A, platelet-derived growth factor, fibroblast growth factor, and transforming growth factor ß. Gamma camera images documented better tissue perfusion in animals treated with MSCs. CONCLUSIONS: The protective effects of MSCs are mediated by the inhibition of apoptosis through immunomodulatory, antioxidative, and angiogenic actions.

Agmatine co-treatment attenuates allodynia and structural abnormalities in cisplatin-induced neuropathy in rats.

Cisplatin is a widely used antineoplastic agent in the treatment of various cancers. Peripheral neuropathy is a well-known side effect of cisplatin and has potential to result in limiting and/or reducing the dose, decreasing the quality of life. Thus, effective treatments are needed. Agmatine is an endogenous neuromodulator that has been shown to exert antiallodynic effects in various animal studies. The first aim of this study was to investigate the in vitro effects of agmatine on cisplatin-induced neurotoxicity. Primary cultures of dorsal root ganglia (DRG) which are the primary target of drug injury were prepared. DRG cells were incubated with cisplatin (100, 200, 500 µm). Then, agmatine (10, 100, 500 µm) was administered with the submaximal concentration of cisplatin. Cisplatin caused concentration-dependent neurotoxicity, and agmatine did not alter this effect. The second aim was to investigate the effects of agmatine on cisplatin-induced peripheral neuropathy in rats and the influence of nitric oxide synthase (NOS) inhibitor, L-NAME, in this effect. Female Sprague Dawley rats received intraperitoneal saline (control), cisplatin (3 mg/kg), cisplatin+agmatine (100 mg/kg), or cisplatin+agmatine+L-NAME (10 mg/kg) once a week for 5 weeks. The mechanical allodynia, thermal hyperalgesia [corrected], and tail clip tests were performed, and DRG cells and sciatic nerves were analyzed. Agmatine and agmatine+L-NAME combination attenuated CIS-induced mechanical allodynia and degeneration in DRG cells and sciatic nerves. However, L-NAME did not potentiate the antiallodynic or neuroprotective effect of agmatine. These findings indicate that agmatine co-administration ameliorates cisplatin-induced neuropathy and may be a therapeutic alternative.