The Effect of Dextrose Hypotonic vs Saline Hydration on Methotrexate-Induced Nephrotoxicity in Male and Female Rats.

Background: High-dose methotrexate (HDMTX) as a cytotoxic agent might cause various side effects. Hyperhydration has been implemented as the major strategy to decrease the potential risk of toxicities induced by HDMTX. This study aims to assess the renoprotective effect of hydration with dextrose water (DW) 5% versus normal saline (N/S) 0.9% against methotrexate (MTX) induced nephrotoxicity. Materials and Methods: This experimental animal study has been conducted on 36 Wistar rats (200-250 g) categorized into six groups, including male (n = 6) and female (n = 6) rats receiving sodium chloride 0.9% saline plus MTX, DW 5% plus MTX, or MTX alone. By the fifth day after the MTX injection, biochemical indexes were measured. The rats were also sacrificed and renal specimens were evaluated microscopically to determine kidney tissue damage (KTD). Results: The groups were not significantly different with regard to blood urea nitrogen (BUN) (P = 0.5), creatinine (Cr) (P = 0.24), kidney weight (P = 0.34), and urine flow (UF) (P = 0.5), while KTD score was remarkably less in the hydrated groups (P < 0.001). Weight loss in DW-treated rats was significantly more than N/S-treated ones, and creatinine clearance (CrCl) and urine load (UL) of Cr were statistically similar between males and females in the control group, but significantly lower among the DW5% treated males. Conclusion: Based on the findings of this study, hydration with N/S was superior to DW5% for the prevention from HDMTX-induced nephrotoxicity. Besides, we found insignificant differences between male versus female rats in response to the hydration for HDMTX-induced renoprotection; however, females probably benefit more.

Latent toxoplasmosis impairs learning and memory yet strengthens short-term and long-term hippocampal synaptic plasticity at perforant pathway-dentate gyrus, and Schaffer collatterals-CA1 synapses.

Investigating long-term potentiation (LTP) in disease models provides essential mechanistic insight into synaptic dysfunction and relevant behavioral changes in many neuropsychiatric and neurological diseases. Toxoplasma (T) gondii is an intracellular parasite causing bizarre changes in host's mind including losing inherent fear of life-threatening situations. We examined hippocampal-dependent behavior as well as in vivo short- and long-term synaptic plasticity (STP and LTP) in rats with latent toxoplasmosis. Rats were infected by T. gondii cysts. Existence of REP-529 genomic sequence of the parasite in the brain was detected by RT-qPCR. Four and eight weeks after infection, spatial, and inhibitory memories of rats were assessed by Morris water maze and shuttle box tests, respectively. Eight weeks after infection, STP was assessed in dentate gyrus (DG) and CA1 by double pulse stimulation of perforant pathway and Shaffer collaterals, respectively. High frequency stimulation (HFS) was applied to induce LTP in entorhinal cortex-DG (400 Hz), and CA3-CA1 (200 Hz) synapses. T. gondii infection retarded spatial learning and memory performance at eight weeks post-infection period, whereas inhibitory memory was not changed. Unlike uninfected rats that normally showed paired-pulse depression, the infected rats developed paired-pulse facilitation, indicating an inhibitory synaptic network disruption. T. gondii-infected rats displayed strengthened LTP of both CA1-pyramidal and DG-granule cell population spikes. These data indicate that T. gondii disrupts inhibition/excitation balance and causes bizarre changes to the post-synaptic neuronal excitability, which may ultimately contribute to the abnormal behavior of the infected host.

Protein Kinase C Involvement in Neuroprotective Effects of Thymol and Carvacrol Against Toxicity Induced by Amyloid-ß in Rat Hippocampal Neurons.

Introduction: We have reported that thymol and carvacrol can improve cognitive abilities in Alzheimer Disease (AD) rat models. However, the mechanism of their action is not yet fully understood. Recently, our in vitro results suggested that PC12 cell death induced by Aß25-35 can be protected by thymol and carvacrol via Protein Kinase C (PKC) and Reactive Oxygen Species (ROS) pathways. So, we hypothesize that the mechanisms of thymol and carvacrol in improving the learning impairment in the AD rat model may be related to their effects on PKC. So, the activity of PKC and protein expression levels of PKCα were examined in the hippocampal cells of the AD rat model. Methods: To examine the thymol and carvacrol effects, we performed a behavioral test in AD rat models induced by Aß25-35 neurotoxicity. To access the underlying mechanism of the protective effects, western blotting was performed with antibodies against PKCα. We also measured the PKC activity assay by Elisa. Histopathological studies were carried out in the hippocampus with Hematoxylin and Eosin (H&E) staining. Results: The escape latency increased in Aß-received rats compared to the control group, and thymol and carvacrol reversed this deficit. Furthermore, these compounds could enhance the PKC activity and increase the PKCα expression ratio. Moreover, H&E staining showed that Aß caused shrinkage of the CA1 pyramidal neurons. However, thymol and carvacrol treatments could prevent this effect of Aß peptides. Conclusion: This study suggests that Amyloid-Beta (Aß) results in memory decline and histochemical disturbances in the hippocampus. Moreover, these results revealed that thymol and carvacrol could have protective effects on cognition in AD-like models via PKC activation. Highlights: Rat's ability to find the invisible platform in the Morris Water Maze (MWM) was impaired by Amyloid-Beta (Aß) infusion in the hippocampus, while this effect was reversed by thymol or carvacrol administration.Aß significantly downregulated the Protein Kinase C (PKC) activity in rats' hippocampus.Western blot analysis demonstrated that Aß significantly reduced PKCα protein expression in AD rat model hippocampal cells.The expression ratio of PKCα was upregulated following the injection of thymol and carvacrol in rats.Injection of Aß in the hippocampus resulted in histochemical disturbances in CA1 pyramidal neurons.Carvacrol and thymol can prevent several histological changes induced by Aß. Plain Language Summary: Alzheimer's disease is one of the most important brain diseases in which the learning and memory are impaired. One of the main causes of Alzheimer's disease is the presence of amyloid beta plaques in the neurons. Protein kinase C enzyme reduces amyloid production and accumulation in the brain. In the present study, we tested the possible effects of carvacrol and thymol in a rat model of Alzheimer's disease. Memory impairment was induced in adult rats by intra-cerebral infusion of amyloid ß. One week later, the memory-impaired animals were treated with carvacrol and thymol. Finally, we tested their memory in a Morris water maze apparatus. Furthermore, their hippocampus was dissected and PKC activity and the neuronal injury was evaluated. Our findings exhibited that thymol and carvacrol improved rats' memory performance. In addition, thymol and carvacrol significantly increased PKC activity and prevented neuronal cell loss in the rat hippocampus. This study shows that thymol and carvacrol have beneficial effects on memory and cognitive function via PKC activation.

Sex Difference in MasR Expression and Functions in the Renal System.

Renin-angiotensin system (RAS), as a critical system for controlling body fluid and hemostasis, contains peptides and receptors, including angiotensin 1-7 (Ang 1-7) and Mas receptor (MasR). Ang 1-7 implements its function via MasR. Ang II is another peptide in RAS that performs its actions via two Ang II type 1 and 2 receptors (AT1R and AT2R). The functions of AT2R and MasR are very similar, and both have a vasodilation effect, while AT1R has a vasoconstriction role. MasR affects many mechanisms in the brain, heart, blood vessels, kidney, lung, endocrine, reproductive, skeletal muscle, and liver and probably acts like a paracrine hormone in these organs. The effect of Ang 1-7 in the kidney is complex according to the hydroelectrolyte status, the renal sympathetic nervous system, and the activity level of the RAS. The MasR expression and function seem more complex than Ang II receptors and have interacted with Ang II receptors and many other factors, including sex hormones. Also, pathological conditions including hypertension, diabetes, and ischemia-reperfusion could change MasR expression and function. In this review, we consider the role of sex differences in MasR expression and functions in the renal system under physiological and pathological conditions.

Activating toll-like receptor 4 after traumatic brain injury inhibits neuroinflammation and the accelerated development of seizures in rats.

Toll-like receptor 4 (TLR4) signaling plays a detrimental role in traumatic brain injury (TBI) pathology. Pharmacologic or genetic inactivating TLR4 diminish TBI inflammation and neurological complications. Nonetheless, TLR4 priming alleviates TBI inflammation and seizure susceptibility. We investigated impact of postconditioning with TLR4 agonist monophosphoryl lipid A (MPL) on TBI neuroinflammation and epileptogenesis in rats. TBI was induced in temporo-parietal cortex of rats by Controlled Cortical Impact device. Then rats received a single dose (0.1 µg/rat) of MPL by intracerebroventricular injection. After 24 h, CCI-injured rats received intraperitoneal injection of pentylenetetrazole 35 mg/kg once every other day until acquisition of generalized seizures. The injury size, number of survived neurons, and brain protein level of TNF-α, TGF-ß, IL-10, and arginase1 (Arg1) were determined. Astrocytes and macrophage/microglia activation/polarization was assessed by double immunostaining with anti GFAP/Arg1 or anti Iba1/Arg1 antibodies. The CCI-injured rats developed generalized seizures after 5.9 ± 1.3 pentylenetetrazole injections (p < 0.001, compared to 12.3 ± 1.4 injections for sham-operated rats). MPL treatment returned the accelerated rate of epileptogenesis in TBI state to the sham-operated level. MPL did not change damage volume but attenuated number of dead neurons (p < 0.01). MPL decreased TNF-α overexpression (6 h post-TBI p < 0.0001), upregulated expression of TGF-ß (48 h post-TBI, p < 0.0001), and IL-10 (48 h post-TBI, p < 0.0001) but did not change Arg1 expression. GFAP/Arg1 and Iba1/Arg1 positive cells were detected in TBI area with no significant change following MPL administration. MPL administration after TBI reduces vulnerability to seizure acquisition through down regulating neural death and inflammation, and up-regulating anti-inflammatory cytokines. This capacity along with the clinical safety, makes MPL a potential candidate for development of drugs against neurological deficits of TBI.

Estradiol Supplement or Induced Hypertension May Attenuate the Angiotensin II Type 1 Receptor Antagonist-Promoted Renal Blood Flow Response to Graded Angiotensin II Administration in Ovariectomized Rats.

Backgrounds: Estrogen replacement therapy (ERT) and hypertension may influence females' renin-angiotensin system (RAS) and its components. The angiotensin II (Ang II) type 1 receptor (AT1R) antagonist (losartan) may promote renal blood flow (RBF), and it is widely used in the clinic to control hypertension. The main objective of this study was the effects of estradiol or induced hypertension on RBF response to Ang II in losartan-treated ovariectomized (OVX) rats. Methods: Two groups of OVX rats were treated with placebo (group 1) and estradiol (group 2) for period of four weeks, and another group of OVX rats was subjected to induce hypertension by two-kidney one clip (2K1C) model (group 3). All the groups were subjected to the surgical procedure under anesthesia, and AT1R was blocked by losartan. RBF and renal vascular resistance (RVR) responses to Ang II administration were determined and compared. Results: Mean arterial (MAP) and renal perfusion (RPP) pressures in group 3 and uterus weight (UT) in group 2 were significantly more than other groups (P < 0.05). Ang II infusion resulted in dose-related percentage change increase in RBF and decrease in RVR. However, these responses in the OVX-estradiol and OVX-hypertensive rats were significantly lower than in the OVX-control group (P < 0.05). For instance, at the dose of 1000 ng/kg/min of Ang II administration, the percentage change of RBF was 45.1 ± 10.4%, 17.9 ± 2.3%, and 16.7 ± 4.7% in the groups of 1 to 3, respectively. Conclusion: Losartan prescription in some conditions such as hypertension or ERT could worsen RBF and RVR responses to Ang II.

Neuroprotective effects of carvacrol against Alzheimer's disease and other neurodegenerative diseases: A review.

Objective: Neurodegenerative diseases are considered an important cause of cognitive deficit and morbidity in old ages. Alzheimer's disease (AD) is one of these disorders affecting about 40 million people in the world at the present time. Available drug therapy is mostly symptomatic and does not modify or stop disease progression. Recently, biologically active chemicals from herbs have been studied to develop new therapeutic drugs. Carvacrol has shown positive properties on many neurological diseases. This compound is expected to have the ability to affect AD pathogenesis and therefore, it is considered an anti-AD agent. Materials and Methods: This review was conducted using PubMed, Google Scholar and Science Direct bibliographic databases until November 2021. For data collection, the following keywords were used: carvacrol, neuroprotective, cognition, anti-inflammatory, antioxidant, Acetylcolinesterase inhibitor (AChEI), Alzheimer's, Parkinson's, epilepsy, stroke, ischemic brain injury, and neurodegenerative diseases. Results: This review summarizes in vitro and in vivo studies on protective potential of carvacrol in neurodegenerative disorders and various underlying mechanisms, such as anti-inflammatory, antioxidant, and anticholinesterase effects. Conclusion: We gave an overview of available literature concerning neuroprotective effects of carvacrol in ameliorating the neurodegenerative diseases symptoms in vivo and in vitro. Particular attention is given to AD. Several neuro-pharmacological actions of carvacrol have been summarized in the current review article including anti-inflammatory, antioxidant, and AChEI properties.

Vitamin D3 mediates spatial memory improvement through nitric oxide mechanism in demyelinated hippocampus of rat

Abstract Studies have revealed beneficial role of vitamin D3 in neuro-cognitive function. There is also supporting evidence on the involvement of nitric oxide (NO) in the neuro-protective action. However, its over production could contribute to brain disorders. In this study, demyelination was induced by ethidium bromide (EB) injection into the right side of the hippocampus area of male rats. Vitamin D3 was administered to rats for 7 and 28 days prior to behavioral experiments using Morris water maze (MWM). Travelled distance, time spent to reach the platform, and time spent in target zone, were considered for learning and spatial memory evaluation. Nitrite oxide (NO2-) concentration was measured as an indicator for nitric oxide production. The time spent to reach the platform and the travelled distance were decreased significantly by 28 days of vitamin D3 administration (compared to 7 days experiment). Time spent in target quadrant was significantly lowered by administered vitamin on day 28. Therefore, considering a number of studies that have shown the effect of vitamin D3 on cognition, these findings could support their potential effect. Besides, nitric oxide concentration significantly differed in 28 days of vitamin D3 treated group compared with the groups treated with EB or 7 days of vitamin D3.

Valproic Acid Inhibits Chronic Toxoplasma Infection and Associated Brain Inflammation in Mice.

Individuals infected with Toxoplasma gondii are prone to psychobehavioral disorders, most notably schizophrenia and bipolar disorder. Valproic acid reportedly inhibits the proliferation of T. gondii tachyzoites in vitro. However, animals treated with the drug neither lived longer during acute infection nor had fewer brain cysts upon chronic infection. In this study, a quantitative real-time PCR (qPCR) method was applied to quantify copy numbers of BAG1 (a bradyzoite-specific protein), REP529 DNA (a repetitive DNA fragment of the parasite), and SAG1 (a highly expressed tachyzoite-specific surface protein) in the brains of chronically infected mice treated with valproic acid. The treatment inhibited the infection and decreased BAG1, SAG1, and REP529 copy numbers in mice brains (P < 0.0001), comparable to the effects of trimethoprim-sulfamethoxazole (TMP-SMZ), the common medication for toxoplasmosis treatment. Moreover, valproic acid decreased brain tumor necrosis factor alpha (TNF-α) expression (P < 0.0001) comparably to TMP-SMZ. Histological examination of mouse brains showed marked reductions in cyst establishment, perivascular infiltration of lymphocytes, and glial nodules to the same levels as those in the TMP-SMZ group. Our results provide direct evidence for the efficacy of valproic acid, a mood-stabilizing and antipsychotic drug, against chronic Toxoplasma infection. These results might help modulate therapeutic regimens for neuropsychiatric patients and aid in the design of more effective anti-Toxoplasma drugs.

Non-selective COX inhibitors impair memory formation and short-term but not long-term synaptic plasticity.

Cyclooxygenase (COX) plays a critical role in synaptic plasticity. Therefore, long-term administration of acetylsalicylic acid (ASA) and its main metabolite, salicylate, as a COX inhibitor may impair synaptic plasticity and subsequently memory formation. Although different studies have tried to explain the effects of ASA and sodium salicylate (SS) on learning and memory, the results are contradictory and the mechanisms are not exactly known. The present study was designed to investigate the effects of long-term low-dose (equivalent to prophylactic dose) and short-term high-dose (equivalent to analgesic dose) administration of ASA and SS respectively, on spatial learning and memory and hippocampal synaptic plasticity. Animals were treated with a low dose of ASA (2 mg/ml solvated in drinking water, 6 weeks) or a high dose of SS, a metabolite of ASA, (300 mg/kg, 3 days, twice-daily, i.p). Spatial memory and synaptic plasticity were assessed by water maze performance and in vivo field potential recording from CA1, respectively. Animals treated with ASA but not SS showed a significant increase in escape latency and distance moved. Furthermore, in the probe test, animals treated with both drugs spent less time in the target quadrant zone. The paired-pulse ratio (PPR) at 20-ms inter-pulse intervals (IPI) as an index of short-term plasticity in both treated groups was significantly higher than of the control group. Interestingly, none of the administered drugs affected long-term potentiation (LTP). These data suggested that long-term inhibition of COX disrupted memory acquisition and retrieval. Interestingly, cognitive impairments happened along with short-term but not long-term synaptic plasticity disturbance.

Renal Vascular Response to Angiotensin II Administration in Two Kidneys-One Clip Hypertensive Rats Treated with High Dose of Estradiol: The Role of Mas Receptor.

BACKGROUNDS: High blood pressure is one of the most important causes of death around the world. The renin-angiotensin system (RAS) and estradiol are two important items that regulate arterial blood pressure in women. However, hypertension, RAS, and sex hormone estradiol may influence renal vascular responses. This study was designed to determine the role of Mas receptor (MasR) on renal vascular response to angiotensin II (Ang II) administration in two kidneys-one clip (2K1C) hypertensive rats treated with estradiol. METHOD: The ovariectomized rats were subjected to 2K1C or non-2K1C and simultaneously treated with estradiol (500 µg/kg/weekly) or placebo for a period of 4 weeks. Subsequently, under anesthesia, renal vascular responses to graded doses of Ang II administration with MasR blockade (A779) or its vehicle were determined. RESULTS: A779 or its vehicle did not alter mean arterial pressure (MAP), renal perfusion pressure (RPP), and renal blood flow (RBF). However, in non-2K1C rats, Ang II infusion decreased RBF and increased renal vascular resistance (RVR) responses in a dose-related manner (Ptreat < 0.0001). The greatest responses were found in ovariectomized estradiol-treated rats that received A779 (Pgroup < 0.05) in non-2K1C rats. Such findings were not detected in 2K1C hypertensive rats. For example, in estradiol-treated rats that received A779, at 1000 ng/kg/min of Ang II infusion, RBF reduced from 1.6 ± 0.2 to 0.89 ± 0.19 ml/min in non-2K1C rats, and it reduced from 1.6 ± 0.2 to 1.2 ± 0.2 ml/min in 2K1C rats. CONCLUSION: Hypertension induced by 2K1C may attenuate the role of A779 and estradiol in renal vascular responses to Ang II infusion. Perhaps, this response can be explained by the reduction of Ang II type 1 receptor (AT1R) expression in the 2K1C hypertensive rats.

Cardioprotective effects of acute sleep deprivation on ischemia/reperfusion injury.

OBJECTIVES: Modulation of sympathetic activity during acute sleep deprivation can produce various effects on body functions. We studied the effects of acute sleep deprivation before ischemia/reperfusion on myocardial injury in isolated rat hearts, and the role of sympathetic nervous system that may mediate these sleep deprivation induced effects. METHODS: The animals were randomized into four groups (n = 11 per group): Ischemia- Reperfusion group (IR), Acute sleep deprivation group (SD), Control group for sleep deprivation (CON-SD) and Sympathectomy + ASD group (SYM-SD). In SD group, sleep deprivation paradigm was used 24 h prior to induction of ischemia/reperfusion. In SYM-SD group, the animals were chemically sympathectomized using 6-hydroxydopamine, 24 h before sleep deprivation. Then, the hearts of animals were perfused using Langendorff setup and were subjected to 30 min regional ischemia followed by 60 min of reperfusion. Throughout the experiment, the hearts were allowed to beat spontaneously and left ventricular developed pressure (LVDP) and rate pressure product (RPP) were recorded. At the end of study, infarct size and percentage of the area at risk were determined. RESULTS: We found that SD increased LVDP and RPP, while reducing the myocardial infarct size. Moreover, sympathectomy reversed SD induced reduction in infarct size and showed no differences as compared to IR. CONCLUSION: This study shows cardioprotective effects of acute sleep deprivation, which can be abolished by chemical sympathectomy in isolated hearts of rats.

Modulation of serotonin signaling/metabolism by Akkermansia muciniphila and its extracellular vesicles through the gut-brain axis in mice.

Several studies have reported that the host-microbe interactions in the gut modulate the host serotonin or 5-hydroxytryptamine (5-HT) system. Here, we evaluated the effects of Akkermansia muciniphila and its extracellular vesicles (EVs) on genes pertaining to the serotonergic system in the colon and hippocampus of mice. Male C57BL/6J mice were administered viable A. muciniphila and its EVs for 4 weeks. The serotonin levels in the colon, hippocampus, and serum of mice, as well as the human colon carcinoma cells (Caco-2), were measured by ELISA assays. Also, the effects of A. muciniphila and its EVs on the expression of serotonin system genes in the colon and hippocampus were examined. A. muciniphila and its EVs may have a biological effect on the induction of serotonin levels in the colon and hippocampus of mice. Also, EVs increased the serotonin level in the Caco-2 cell line. In contrast, both treatments decreased the serotonin level in the serum. Both the bacterium and its EVs had significant effects on the mRNA expression of genes, involved in serotonin signaling/metabolism in the colon and hippocampus of mice. Moreover, A. muciniphila and its EVs affected the mRNA expression of inflammatory cytokines (Il-10 and Tnf-α) in the colon, however, there is no significant difference in inflammatory cell infiltrate in the histopathology of the colon. The presence of A. muciniphila and its EVs in the gut promotes serotonin concentration, they also affect serotonin signaling/metabolism through the gut-brain axis and may be considered in new therapeutic strategies to ameliorate serotonin-related disorders.

Two Novel Compounds with Tri-aryl Structures as Effective Anti-Breast Cancer Candidates In-vivo.

Prognosis of metastatic breast cancer is very poor which urges the necessity to develop novel potential drug candidates. We assessed two compounds with tri-aryl structures (A and B) for their potency to reduce primary breast tumor growth and lung metastasis in 4T1 mice model. MTT assay, 4T1 mammary mouse model, and immunohistochemistry experiments were used in this study. In-vitro results exhibited an anti-proliferative effect for compounds A and B towards MDA-MB-231 cancer cells. Our in-vivo results displayed that administered compounds A and B could suppress the size of the primary tumor and the number of lung metastatic foci in 4T1 BALB/c mice model. Histopathological analysis revealed that treatment of both compounds resulted in necrosis. Our findings provide new evidence that compound B may be promising for slowing the growth of tumor along with metastatic foci via COX-2 independent pathway.

Topical hydrogel containing Fumaria vaillantii Loisel. extract enhances wound healing in rats.

BACKGROUND: Fumaria species (Fumariacea) has traditionally been used in wound healing in Iranian folk medicine. However, with the discovery of newer agents, its use has faded off into total obscurity. This study explored the wound healing potential of a gel containing 10% Fumaria vaillantii Loisel through topical application of total extract in a model of excisional as well as incisional wound healing in albino Wistar rats. METHODS: Rats were anesthetized, and excisional skin wound was established using a sterilized surgical scissors. The animals were then treated with 10% F.vaillantii topical gel formulation along with the gel base. The treatments were administered once a day after the injury for 21 days. For topical treatment, the hydrogel was formulated and evaluated for chemical and physical characteristics. Histopathological analysis with hematoxylin and eosin (H&E) was used for microscopic examination of the skin tissues on 21-day-old sections of excision wound. To verify collagen formation, hydroxyproline determination was performed 21 days post wound healing. Breaking strength was determined in a 10-day-old incision wound by the uniaxial tensile test. RESULTS: Topical administration of F.vaillantii gel formulation significantly enhanced skin wound closure on the 6th post-wounding day compared to both gel base and the negative control, indicating an accelerated wound healing process, while a significant difference was observed on 10th and 14th post -wound days in F.vaillantii treatment compared to the negative control groups. Gel formulation prepared with a 10% F. vaillantii extract exhibited a response in terms of wound epithelialization, angiogenesis and number of hair follicles at wound area better than the gel base on the 21st post-wound day. Application of gel base produced further advantages by increasing hydroxyproline content and collagen fiber thickness. Our results on incision wound model were supported by histopathological data indicating the role of gel base in the enhancement of breaking strength. CONCLUSION: Traditional use of Fumaria species in the skin diseases was justified in this study by revealing the increase in wound healing activity after hydrogel containing F. vaillantii total extract administration.

Two Novel Tri-Aryl Derivatives Attenuate the Invasion-Promoting Effects of Stromal Mesenchymal Stem Cells on Breast Cancer.

BACKGROUND: The concept of Epithelial-Mesenchymal Transition (EMT) to promote carcinoma progression has been recognized as a venue for research on novel anticancer drugs. Triaryl template-based structures are one of the pivotal structural features found in a number of compounds with a wide variety of biological properties including anti-breast cancer. Among the various factors triggering EMT program, cyclooxygenase-2 (COX-2), NF-κB as well as the transforming growth factor-beta (TGF-ß) have been widely investigated. OBJECTIVE: Here, we aim to investigate the effect of two novel compounds A and B possessing triaryl structures, which interact with both COX-2 and TGF-ß active sites and suppress NF-κB activation, on EMT in a co-culture system with breast cancer and stromal cells. METHODS: MDA-MB-231 and bone-marrow mesenchymal stem (BM-MS) cells were co-cultured in a trans-well plate. Migration, matrigel-based invasion and colony formation in soft agar assays along with Real- time PCR and Western blot analysis were performed to examine the effect of compounds A and B on the invasive properties of MDA-MB-231 cells after 72 hours of co-culturing with BM-MSCs. In addition, TGF-beta interaction was investigated by Localized Surface Plasmon Resonance (LSPR). RESULTS: BM-MSCs enhanced migration, invasion and anchorage-independent growth of the co-cultured MDAMB- 231 cells. A reduction in E-cadherin level concomitant with an increase in vimentin and N-cadherin levels following the co-culture implied EMT as the underlying process. Compounds A and B inhibited invasion and anchorage-independent growth of breast cancer cells co-cultured with BM-MSCs at 10µM. The observed inhibitory effects along with an increase in E-cadherin and a reduction in vimentin and ZEB2 levels suggest that the anti-invasive properties of compounds A and B might proceed through the blockade of stromal cell-induced EMT, mediated by their interaction with TGF-beta. CONCLUSION: These findings introduce compounds A and B as novel promising agents, which prevent EMT in invasive breast cancer cells.

Early minor stimulation of microglial TLR2 and TLR4 receptors attenuates Alzheimer's disease-related cognitive deficit in rats: behavioral, molecular, and electrophysiological evidence.

At early stages of Alzheimer's disease (AD), soluble amyloid beta (Aß) accumulates in brain while microglia are in resting state. Microglia can recognize Aß long after formation of plaques and release neurotoxic mediators. We examined impact of early minor activation of microglia by Toll-like receptors (TLRs) 2 and 4 agonists on Alzheimer's disease-related disturbed synaptic function and spatial memory in rats. Microglial BV-2 cells were treated by 0.1, 1, and 10 µg/mL of the TLRs ligands lipopolysaccharide, monophosphoryl lipid A (MPL), and Pam3Cys for 24 hours. Culture medium was then changed with media containing 1-µM Aß. Tumour necrosis factor (TNF)-α and CCL3 levels were measured in the supernatant, 24 hours thereafter. One µg of TLRs ligands which was able to release low level of TNF-α and CCL3, was administered intracerebroventricularly (i.c.v) to adult male rats every 3 days for 24 days. At the half of the treatment period, Aß1-42 was infused i.c.v (0.075 µg/hour) for 2 weeks. Finally, the following factors were measured: memory performance by Morris water maze, postsynaptic potentials of dentate gyrus following perforant pathway stimulation, hippocampal inflammatory cytokines interleukin 1 (IL-1)ß and TNF-α, anti-inflammatory cytokines IL-10 and TGF-1ß, microglia marker arginase 1, Aß deposits, and the receptor involved in Aß clearance, formyl peptide receptor 2 (FPR2). TLRs ligands caused dose-dependent release of TNF-α and CCL3 by BV-2 cells. Aß-treated cells did not release TNF-α and CCL3, whereas those pretreated with MPL and Pam3Cys significantly released these cytokines in response to Aß. Low-dose TLRs ligands improved the disturbance in spatial and working memory; restored the impaired long-term potentiation induced by Aß; decreased TNF-α, and Aß deposits; enhanced TGF-1ß, IL-10, and arginase 1 in the hippocampus of Aß-treated rats; and increased polarization of hippocampal microglia to the anti-inflammatory phenotype. The ligands increased formyl peptide receptor 2 in both BV-2 cells and hippocampus/cortex of Aß-treated rats. Microglia can sense/clear soluble Aß by early low-dose MPL and Pam3Cys and safeguard synaptic function and memory in rats.

Toxoplasmosis accelerates acquisition of epilepsy in rats undergoing chemical kindling.

Epilepsy is one of the most common neurologic disorders worldwide with no distinguishable cause in 60% of patients. One-third of the world population has been infected with Toxoplasma gondii. This intracellular parasite has high tropism for excitable cells including neurons. We assessed impact of acute and chronic T. gondii infection on epileptogenesis in pentylenetetrazole (PTZ) kindling model in male rats. T. gondii cysts were administered to rats by intraperitoneal (i.p.) injection. The presence of T. gondii cysts in the brain of rats was verified by hematoxylin-eosin staining. One and eight weeks after cysts injection, as acute and chronic phases of infection, PTZ (30mg/kg, i.p.) was injected to the rats every other day until manifestation of generalized seizures. Histologic findings confirmed cerebral toxoplasmosis in rats. The rats with acute or chronic Toxoplasma infection became kindled by lower number of PTZ injections (14.8±1 and 13.6±1 injections, respectively) compared to corresponding uninfected rats (18.7±1 and 16.9±1 injections, p<0.05). Toxoplasma infection increased the rate of kindling in rats. The chronically-infected rats achieved focal and also generalized seizures earlier than the rats with acute infection. Toxoplasmosis might be considered as a risk factor for acquisition of epilepsy.

Effect of Lactation on myocardial vulnerability to ischemic insult in rats / Efeito da Lactação sobre a Vulnerabilidade do Miocárdio ao Insulto Isquêmico em Ratas

Abstract Background: Cardiovascular diseases are the leading cause of mortality and long-term disability worldwide. Various studies have suggested a protective effect of lactation in reducing the risk of cardiovascular diseases. Objective: This study was designed to assess the effects of pregnancy and lactation on the vulnerability of the myocardium to an ischemic insult. Methods: Eighteen female rats were randomly divided into three groups: ischemia-reperfusion (IR), in which the hearts of virgin rats underwent IR (n = 6); lactating, in which the rats nursed their pups for 3 weeks and the maternal hearts were then submitted to IR (n = 6); and non-lactating, in which the pups were separated after birth and the maternal hearts were submitted to IR (n = 6). Outcome measures included heart rate (HR), left ventricular developed pressure (LVDP), rate pressure product (RPP), ratio of the infarct size to the area at risk (IS/AAR %), and ventricular arrhythmias - premature ventricular contraction (PVC) and ventricular tachycardia (VT). Results: The IS/AAR was markedly decreased in the lactating group when compared with the non-lactating group (13.2 ± 2.5 versus 39.7 ± 3.5, p < 0.001) and the IR group (13.2 ± 2.5 versus 34.0 ± 4.7, p < 0.05). The evaluation of IR-induced ventricular arrhythmias indicated that the number of compound PVCs during ischemia, and the number and duration of VTs during ischemia and in the first 5 minutes of reperfusion in the non-lactating group were significantly (p < 0.05) higher than those in the lactating and IR groups. Conclusion: Lactation induced early-onset cardioprotective effects, while rats that were not allowed to nurse their pups were more susceptible to myocardial IR injury.

Resumo Fundamento: As doenças cardiovasculares são a principal causa de mortalidade e invalidez a longo prazo a nível mundial. Diversos estudos têm sugerido um efeito protetor da lactação na redução do risco para doenças cardiovasculares. Objetivo: Este estudo foi desenvolvido para avaliar os efeitos da gestação e da lactação sobre a vulnerabilidade do miocárdio ao insulto isquêmico. Métodos: Dezoito ratas foram divididas aleatoriamente em três grupos: isquemia-reperfusão (IR), no qual os corações de ratas virgens foram submetidos à IR (n = 6); lactantes, no qual as ratas amamentaram seus filhotes por 3 semanas e os corações maternos foram, em seguida, submetidos à IR (n = 6); e não lactantes, no qual os filhotes foram separados após o nascimento e os corações maternos foram submetidos à IR (n = 6). As medidas de desfecho incluíram frequência cardíaca (FC), pressão desenvolvida no ventrículo esquerdo (PDVE), duplo produto (DP), razão do tamanho do infarto sobre a área sob risco (TI/ASR %) e arritmias ventriculares - contração ventricular prematura (CVP) e taquicardia ventricular (TV). Resultados: O TI/ASR foi substancialmente menor no grupo de lactantes quando comparado ao grupo de não lactantes (13,2 ± 2,5 versus 39,7 ± 3,5, p < 0,001) e ao grupo IR (13,2 ± 2,5 versus 34,0 ± 4,7, p < 0,05). A avaliação das arritmias ventriculares induzidas pela IR indicou que o número de CVPs compostas na isquemia, e o número e a duração das TVs na isquemia e nos primeiros 5 minutos de reperfusão no grupo de não lactantes foram significativamente (p < 0,05) mais elevados do que os encontrados nos grupos IR e de lactantes. Conclusão: A lactação induziu o aparecimento precoce de efeitos cardioprotetores, enquanto ratas que não foram permitidas a amamentar seus filhotes se mostraram mais suscetíveis à lesão miocárdica por IR.

Effect of Lactation on myocardial vulnerability to ischemic insult in rats.

Background: Cardiovascular diseases are the leading cause of mortality and long-term disability worldwide. Various studies have suggested a protective effect of lactation in reducing the risk of cardiovascular diseases. Objective: This study was designed to assess the effects of pregnancy and lactation on the vulnerability of the myocardium to an ischemic insult. Methods: Eighteen female rats were randomly divided into three groups: ischemia-reperfusion (IR), in which the hearts of virgin rats underwent IR (n = 6); lactating, in which the rats nursed their pups for 3 weeks and the maternal hearts were then submitted to IR (n = 6); and non-lactating, in which the pups were separated after birth and the maternal hearts were submitted to IR (n = 6). Outcome measures included heart rate (HR), left ventricular developed pressure (LVDP), rate pressure product (RPP), ratio of the infarct size to the area at risk (IS/AAR %), and ventricular arrhythmias - premature ventricular contraction (PVC) and ventricular tachycardia (VT). Results: The IS/AAR was markedly decreased in the lactating group when compared with the non-lactating group (13.2 ± 2.5 versus 39.7 ± 3.5, p < 0.001) and the IR group (13.2 ± 2.5 versus 34.0 ± 4.7, p < 0.05). The evaluation of IR-induced ventricular arrhythmias indicated that the number of compound PVCs during ischemia, and the number and duration of VTs during ischemia and in the first 5 minutes of reperfusion in the non-lactating group were significantly (p < 0.05) higher than those in the lactating and IR groups. Conclusion: Lactation induced early-onset cardioprotective effects, while rats that were not allowed to nurse their pups were more susceptible to myocardial IR injury.

Fundamento: As doenças cardiovasculares são a principal causa de mortalidade e invalidez a longo prazo a nível mundial. Diversos estudos têm sugerido um efeito protetor da lactação na redução do risco para doenças cardiovasculares. Objetivo: Este estudo foi desenvolvido para avaliar os efeitos da gestação e da lactação sobre a vulnerabilidade do miocárdio ao insulto isquêmico. Métodos: Dezoito ratas foram divididas aleatoriamente em três grupos: isquemia-reperfusão (IR), no qual os corações de ratas virgens foram submetidos à IR (n = 6); lactantes, no qual as ratas amamentaram seus filhotes por 3 semanas e os corações maternos foram, em seguida, submetidos à IR (n = 6); e não lactantes, no qual os filhotes foram separados após o nascimento e os corações maternos foram submetidos à IR (n = 6). As medidas de desfecho incluíram frequência cardíaca (FC), pressão desenvolvida no ventrículo esquerdo (PDVE), duplo produto (DP), razão do tamanho do infarto sobre a área sob risco (TI/ASR %) e arritmias ventriculares - contração ventricular prematura (CVP) e taquicardia ventricular (TV). Resultados: O TI/ASR foi substancialmente menor no grupo de lactantes quando comparado ao grupo de não lactantes (13,2 ± 2,5 versus 39,7 ± 3,5, p < 0,001) e ao grupo IR (13,2 ± 2,5 versus 34,0 ± 4,7, p < 0,05). A avaliação das arritmias ventriculares induzidas pela IR indicou que o número de CVPs compostas na isquemia, e o número e a duração das TVs na isquemia e nos primeiros 5 minutos de reperfusão no grupo de não lactantes foram significativamente (p < 0,05) mais elevados do que os encontrados nos grupos IR e de lactantes. Conclusão: A lactação induziu o aparecimento precoce de efeitos cardioprotetores, enquanto ratas que não foram permitidas a amamentar seus filhotes se mostraram mais suscetíveis à lesão miocárdica por IR.