Cilostazol pretreatment prevents PTSD-related anxiety behavior through reduction of hippocampal neuroinflammation

Current pharmacological treatments against post-traumatic stress disorder (PTSD) lack adequate efficacy. As a result, intense research has focused on identifying other molecular pathways mediating the pathogenesis of this condition. One such pathway is neuroinflammation, which has demonstrated a role in PTSD pathogenesis by causing synaptic dysfunction, neuronal death, and functional impairment in the hippocampus. Phosphodiesterase (PDE) inhibitors (PDEIs) have emerged as promising therapeutic agents against neuroinflammation in other neurological conditions. Furthermore, PDEIs have shown some promise in animal models of PTSD. However, the current model of PTSD pathogenesis, which is based on dysregulated fear learning, implies that PDE inhibition in neurons should enhance the acquisition of fear memory from the traumatic event. As a result, we hypothesized that PDEIs may improve PTSD symptoms through inhibiting neuroinflammation rather than long-term potentiation-related mechanisms. To this end, we tested the therapeutic efficacy of cilostazol, a selective inhibitor of PDE3, on PTSD-related anxiety symptoms in the underwater trauma model of PTSD. PDE3 is expressed much more richly in microglia and astrocytes compared to neurons in the murine brain. Furthermore, we used hippocampal indolamine 2,3-dioxygenase 1 (IDO) expression and interleukin 1 beta (IL-1β) concentration as indicators of neuroinflammation. We observed that cilostazol pretreatment prevented the development of anxiety symptoms and the increase in hippocampal IDO and IL-1β following PTSD induction. As a result, PDE3 inhibition ameliorated the neuroinflammatory processes involved in the development of PTSD symptoms. Therefore, cilostazol and other PDEIs may be promising candidates for further investigation as pharmacological therapies against PTSD.

Spermidine reduced neuropathic pain in chronic constriction injury-induced peripheral neuropathy in rats

Neuropathic pain is one of the most critical types of chronic pain despite the increasing advances in medical science. Spermidine (SPD) is a natural polyamine that has wide roles in several cellular processes inducing autophagy and reducing oxidative stress. This study aimed to investigate the effects of SPD on oxidative stress markers and pain threshold in the neuropathic rat model of chronic constriction injury (CCI) model. Eighteen adult male rats were divided into three groups: sham, CCI and CCI+SPD. After induction of neuropathy via CCI model in the CCI and CCI+SPD groups, SPD (1 mg/kg/day, orally) was administered to the CCI+SPD group for 3 weeks. The behavioral tests (von Frey, hot plate) were done four times during the experiment. At the end of the study, electrophysiological tests, the H & E staining, and oxidative stress assay of the prefrontal cortex (PFC), spinal cord, and sciatic nerve were performed. The threshold of pain in hot plate and von Frey tests was significantly lower in the CCI group than in the sham group, which was reversed by SPD treatment in the CCI+ SPD group. In addition, nerve conduction was considerably lower in the CCI group than in the sham and CCI+SPD groups (P < 0.01, P < 0.05, respectively). The CCI group showed neuronal degeneration and fibrosis in the different tissues in the H & E assay; elevated tissues level of nitrite, decreased levels of superoxide dismutase (SOD), glutathione (GPx), and catalase were also observed. However, SPD treatment modulated the pathological changes and oxidative stress biomarkers. In conclusion, SPD showed beneficial effects in decreasing neuropathic pains. SPD treatment reduced oxidative stress and improved histopathological changes and behavioral tests in the CCI-induced neuropathic pain in in vivo model.

Assessment of Sumatriptan on Sepsis-Induced Kidney injury in the Cecal Ligation and Puncture Mice Model

Sepsis is a severe systemic inflammatory response with high mortality rate resulting from different microorganisms. Cytokines activation is essential for the immune response, but in painful conditions like sepsis, cytokines act as a double-edged sword and dysregulate immune response which is life-threatening owing to multiple organ dysfunction. The abnormality in 5-HT function is involved in pathological conditions like irritable bowel syndrome, inflammation, myocardial ischemia, itch and renal injury. Sumatriptan, a 5-HT_1B/1D agonist, has anti-inflammatory and anti-oxidative stress effects on animal models. This study was aimed to assess the effects of sumatriptan on kidney injury, the levels of pro-inflammatory cytokines and the percentage of survival in (CLP)-induced sepsis were examined.Cecal ligation and puncture (CLP) model was done on adult C57BL/6 male mice to induce Polymicrobial sepsis. Sumatriptan was injected intraperitoneally 1 h after the sepsis induction by CLP at doses of 0.1, 0.3, and 1 mg/kg in 3 treatment groups. To study the effect of sumatriptan on short-term survival, septic animals were detected 72 h after CLP. Serum levels of TNF-α, IL-1β, IL-6 and IL-10 were evaluated. To study sepsis-induced acute renal failure, kidney functional biomarkers and histopathological alterations were evaluated.Sumatriptan (0.3 mg/kg) administration significantly enhanced survival rate (P<0.01) compared to the CLP group. The beneficial effects of sumatriptan were related to a significant decrease in the pro-inflammatory cytokines and elevated level of IL-10. Sumatriptan presented protective effects on kidney biomarkers and histopathology assay.Anti-inflammatory effects of sumatriptan lead to decrease mortality rate and inflammatory cytokines in CLP induction sepsis in C57BL/6 mice.

Trifluoperazine reduces cuprizone-induced demyelination via targeting Nrf2 and IKB in mice

Multiple sclerosis (MS) is one of the most common neurodegenerative diseases. In this disease, the immune system attacks oligodendrocyte cells and the myelin sheath of myelinated neurons in the central nervous system, causing their destruction. These conditions lead to impaired conduction of nerve impulses and are manifested by symptoms such as weakness, fatigue, visual and motor disorders. This study aimed to evaluate the ability of trifluoperazine (TF) to improve cuprizone-induced behavioral and histopathological changes in the prefrontal cortex of C57BL/6 male mice. Demyelination was induced by adding 0.2% cuprizone (CPZ) to the standard animal diet for 6 weeks. Three doses of TF (0.5, 1 and 2 mg/kg/day; i.p.) were given once daily for the last 2 weeks of treatment. Treatment with CPZ induced a weight loss during 6 weeks of treatment compared to the control group, which was reversed by the administration of TF. Behavioral tests (pole test and rotarod performance test) showed a decrease in motor coordination and balance in the group treated with CPZ (P < 0.01). Treatment with TF during the last two weeks was able to improve these motor deficiencies. Histopathological examination also evidenced an increase in demyelination in the CPZ group, which was improved by TF administration. In addition, CPZ intake significantly decreased the cerebral cortex levels of p-Nrf2 (P < 0.001) and increased the levels of p-IKB (P < 0.001) and, these changes were normalized in the TF groups. TF administration also reversed the increased levels of nitrite and the reduced activity of the antioxidant enzyme superoxide dismutase associated with CPZ exposure. TF can to reduce the harmful effects of CPZ by reducing the demyelination and modulating the Nrf2 and NF-kB signaling pathways.

Anti-inflammatory efficacy of Berberine Nanomicelle for improvement of cerebral ischemia: formulation, characterization and evaluation in bilateral common carotid artery occlusion rat model

BACKGROUND

Berberine (BBR) is a plant alkaloid that possesses anti-inflammatory and anti-oxidant effects with low oral bioavailability. In this study, micelle formulation of BBR was investigated to improve therapeutic efficacy and examined its effect on the secretion of inflammatory cytokines in cerebral ischemia in the animal model.

MATERIAL AND METHODS

Nano formulation was prepared by thin-film hydration method, and characterized by particle size, zeta potential, morphology, encapsulation efficacy, and drug release in Simulated Gastric Fluid (SGF) and Simulated Intestine Fluid (SIF). Then, Wistar rats were pretreated with the drug (100 mg/kg) and nano-drug (25, 50, 75, 100 mg/kg) for 14 days. Then, on the fourteenth day, stroke induction was accomplished by Bilateral Common Carotid Artery Occlusion (BCCAO); after that, Tumor Necrosis Factor - Alpha (TNF-α), Interleukin - 1 Beta (IL-1ß), and Malondialdehyde (MDA) levels were measured in the supernatant of the whole brain, then the anti-inflammatory effect of BBR formulations was examined.

RESULT AND DISCUSSION

Micelles were successfully formed with appropriate characteristics and smaller sizes than 20 nm. The Poly Dispersity Index (PDI), zeta potential, encapsulation efficacy of micelles was 0.227, - 22 mV, 81%, respectively. Also, the stability of nano micelles was higher in SGF as compared to SIF. Our outcomes of TNF-a, IL-1B, and MDA evaluation show a significant ameliorating effect of the Berberine (BBR) and BBR-loaded micelles in pretreated groups.

CONCLUSION

Our experimental data show that pretreated groups in different doses (nano BBR 100, 75, 50 mg/kg, and BBR 100 mg/kg) successfully showed decreased levels of the inflammatory factors in cerebral ischemia compared with the stroke group and pretreated group with nano BBR in the dose of 25 mg/kg. Nano BBR formulation with a lower dose can be a better candidate than conventional BBR formulation to reduce oxidative and inflammatory factors in cerebral ischemia. Therefore, BBR-loaded micelle formulation could be a promising protective agent on cerebral ischemia.

Evaluation of Anti-inflammatory and Antioxidant Effects of Sumatriptan on Carbon Tetrachloride-induced Hepatotoxicity in Rats

The liver detoxifies and metabolizes many drugs and xenobiotics which may cause hepatotoxicity due to some toxic agents. Carbon tetrachloride (CCl₄) is metabolized in cytochrome P450 and its reactive radical metabolites cause lipid peroxidation, cellular injury, and apoptosis. Sumatriptan (SUM), 5-HT1B/1D receptor agonist, had anti-inflammatory and anti-oxidant effects. In this research the effect of SUM pre-treatment against CCl₄-induced hepatotoxicity was examined. Adult rats received SUM (0.1, 0.3 and 1 mg/kg; i.p.) for 3 consecutive days before CCl₄ (2 ml/kg; i.p. on the 3^rd day). The aminotransferases serum levels, tissue levels of anti-oxidant and pro-inflammatory markers and histopathological examination were evaluated. SUM (0.3 mg/kg) prevented significantly the elevation of aminotransferases versus the control group (CCl₄ group) (P<0.0001) and also, reversed meaningfully the changes of the MPO, MDA, SOD and CAT, IL-1β and TNF-α levels. Additionally, CCl₄-intoxication resulted to the disruption of lobular and cellular structures and inflammation in histopathological evaluation which is prevented by SUM (0.3 mg/kg). These data revealed that SUM (0.3 mg/kg), but no at doses 0.1 and 1 mg/kg, decreases the hepatotoxicity of induced by CCl₄ in rats.

Isofuranodiene, a Natural Sesquiterpene Isolated from Wild Celery (Smyrnium olusatrum L.), Protects Rats against Acute Ischemic Stroke

The myrrh-like furanosesquiterpene isofuranodiene (IFD) is the main constituent of wild celery (Smyrnium olusatrum L., Apiaceae), an overlooked vegetable that was cultivated during the Roman Empire. In the present study, we investigated the protective effects of IFD pre-treatment against oxidative stress and inflammatory response in an animal model of ischemic stroke. IFD was isolated by the crystallization of Smyrnium olusatrum essential oil, and its structure and purity were confirmed by NMR and HPLC analyses. Acute pre-treatment of IFD (10 mg/kg i.p.) significantly reduced the levels of the inflammatory cytokines IL-1β and TNF-α, the expression of pNF-κB/NF-κB, and the lipid peroxidation indicator MDA. Finally, IFD boosted a faster recovery and better scores in grid-walking and modified neurological severity scores (mNSS) tests. Taken together, these findings indicate IFD as a promising lead compound for the discovery of new treatments of brain ischemia.

Chronically altered NMDAR signaling in epilepsy mediates comorbid depression

Depression is the most common psychiatric comorbidity of epilepsy. However, the molecular pathways underlying this association remain unclear. The NMDA receptor (NMDAR) may play a role in this association, as its downstream signaling has been shown to undergo long-term changes following excitotoxic neuronal damage. To study this pathway, we used an animal model of fluoxetine-resistant epilepsy-associated depression (EAD). We determined the molecular changes associated with the development of depressive symptoms and examined their response to various combinations of fluoxetine and a selective neuronal nitric oxide synthase inhibitor, 7-nitroindazole (NI). Depressive symptoms were determined using the forced swim test. Furthermore, expression and phosphorylation levels of markers in the ERK/CREB/ELK1/BDNF/cFOS pathway were measured to determine the molecular changes associated with these symptoms. Finally, oxidative stress markers were measured to more clearly determine the individual contributions of each treatment. While chronic fluoxetine (Flxc) and NI were ineffective alone, their combination had a statistically significant synergistic effect in reducing depressive symptoms. The development of depressive symptoms in epileptic rats was associated with the downregulation of ERK2 expression and ELK1 and CREB phosphorylation. These changes were exactly reversed upon Flxc + NI treatment, which led to increased BDNF and cFOS expression as well. Interestingly, ERK1 did not seem to play a role in these experiments. NI seemed to have augmented Flxc’s antidepressant activity by reducing oxidative stress. Our findings suggest NMDAR signaling alterations are a major contributor to EAD development and a potential target for treating conditions associated with underlying excitotoxic neuronal damage.

The Protective Roles and Molecular Mechanisms of Troxerutin (Vitamin P4) for the Treatment of Chronic Diseases: A Mechanistic Review

Troxerutin (TRX), a semi-synthetic bioflavonoid derived from rutin, has been reported to exert several pharmacological effects including antioxidant, anti-inflammatory, antihyperlipidemic, and nephroprotective. However, the related molecular details and its mechanisms remain poorly understood. In the present review, we presented evidences from the diversity in vitro and in vivo studies on the therapeutic potential of TRX against neurodegenerative, diabetes, cancer and cardiovascular diseases with the purpose to find molecular pathways related to the treatment efficacy. TRX has a beneficial role in many diseases through multiple mechanisms including, increasing antioxidant enzymes and reducing oxidative damage, decreasing in proapoptotic proteins (APAF-1, BAX, caspases-9 and-3) and increasing the antiapoptotic BCL-2, increasing the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and downregulating the nuclear factor κB (NFκ). TRX also reduces acetylcholinesterase activity and upregulates phosphoinositide 3- kinase/Akt signaling pathway in Alzheimer's disease models. Natural products such as TRX may develop numerous and intracellular pathways at several steps in the treatment of many diseases. Molecular mechanisms of action are revealing novel, possible combinational beneficial approaches to treat multiple pathological conditions.

Risperidone attenuates acetic acid-induced colitis in rats through inhibition of TLR4/NF-kB signaling pathway

AIM

The purpose of the present study is to explore the anti-inflammatory potential of risperidone in acetic acid-induced rat colitis through inhibition of TLR4/NF-kB pathway.

METHODS

Acute colitis induction was done by intra-rectal administration of 2 mL of 4% diluted acetic acid solution. Two h after colitis induction, dexamethasone (2 mg/kg) as standard drugorrisperidone (2, 4 and 6 mg/kg) were administered orally to wistar rats for five consecutive days. 24 h after the last treatment, animals were sacrificed by cervical dislocation. Macroscopic and microscopic damage evaluation was done. Biochemical and ELISA methods were used to assess myeloid peroxidase (MPO) enzyme activity and tumor necrosis factor-α (TNF-α) level respectively. Moreover, immunohistochemistry (IHC) was performed to detect the expression of TLR4 and pNF-kBproteins.

RESULTS

Dexamethasone (2 mg/kg) or risperidone (2, 4 and 6 mg/kg) improved acetic acid-induced macroscopic (p < .001) and microscopic lesions. Additionally, risperidone (2, 4 and 6 mg/kg) inhibited the activity of MPO and TNF-α (p < .01, p < .001) in the colon tissue compared to acetic acid group. Furthermore, bothdexamethasone and risperidone (2, 4 and 6 mg/kg) significantly reduced acetic acid-induced expression of TLR4and pNF-kB proteins (p < .05, p < .01, p < .001).

CONCLUSION

The anti-inflammatory effect of risperidone on acetic acid-induced colitis in rats may involve inhibition of TLR4 and NF-kB signaling pathway.

Protective Effects of Leukadherin1 in a Rat Model of Targeted Experimental Autoimmune Encephalomyelitis (EAE): Possible Role of P47phox and MDA Downregulation

Background

Reactive oxygen and nitrogen species (ROS and RNS) are involved in pathologic mechanisms underlying demyelination and exacerbation in multiple sclerosis (MS) lesions. P47phox is the most important subunit of an ROS-producing enzyme (NADPH oxidase) which is reportedly upregulated in MS plaques due to the intense activity of infiltrated immune cells and resident microglia. Leukadherin1 is a specific CD11b/CD18 agonist that inhibits signaling and transmigration of inflammatory cells to sites of injury. Based on this mechanism, we evaluated therapeutic effects of leukadherin1 in an animal model of targeted experimental autoimmune encephalomyelitis (EAE) through focal injection of inflammatory cytokines to the spinal cord.

Methods

For model induction, Lewis rats were first immunized with 15µg MOG 1–125 emulsion. Twenty days later, animals were subjected to stereotaxic injection of IFNγ and TNFα to the specific spinal area (T8). One day after injection, all animals presented EAE clinical signs, and their behaviors were monitored for eight days through open-field locomotion and grid-walking tests. Leukadherin1-treated animals received daily intraperitoneal injections of 1mg/kg of the drug. The specific spinal tissues were extracted on day 5 in order to measure nitric oxide (NO), malon di-aldehyde (MDA), and TNFα concentrations alongside P47phox real-time PCR analysis. In addition, spinal sections were prepared for immunohistochemical (IHC) observation of infiltrated leukocytes and activated microglia.

Results

Leukadherin1 exhibited promising improvements in EAE clinical scores and behavioral tests. Demyelination, CD45+ leukocyte infiltration, and Iba1+ microglia activation were reduced in spinal tissues of leukadherin1-treated animals. Furthermore, P47phox expression levels, MDA, and NO amounts were decreased in treated animals. However, TNFα concentrations did not differ following treatment.

Conclusion

Based on our results, we suggest that leukadherin1 may be used as a novel therapeutic agent in tackling the clinical challenge of multiple sclerosis, especially during the acute phase of the disease. This effect was possibly mediated through decreased leukocyte infiltration and oxidative stress.

The protective effect of modafinil on vincristine-induced peripheral neuropathy in rats: A possible role for TRPA1 receptors

Vincristine (VCR) induces peripheral neuropathy. We aimed to assess the efficacy of modafinil on VCR-induced neuropathy in rats. Neuropathy was induced by intraperitoneal (i.p.) injections of VCR (0.1 mg/kg). Neuropathic groups received modafinil (5, 25 and 50 mg/kg); gabapentin (20 mg/kg); and a combination of modafinil (5 and 50 mg/kg) and gabapentin (20 mg/kg,). Then, electrophysiological, behavioural, biochemical and pathological evaluations were performed. Latencies of tail-flick and von Frey filament tests, motor nerve conduction velocity (MNCV) and excitation of nerve conduction were decreased. Moreover, the transient receptor potential cation channel ankyrin 1 (TRPA1) level was increased, while TRPV1 and N-Methyl-D-aspartate (NMDA) levels remained unchanged. Tumour necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) levels were markedly elevated. Pre-treatment with modafinil prevented sensorimotor neuropathy by raising latencies, MNCV and excitation, reducing TRPA1, TNF-α and IL-1β levels. Modafinil improved behavioural, electrophysiological and pathological disturbances. The results showed that TRPA1 has a more important role than NMDA and TRPV1, in VCR-induced neuropathic pain. In addition, inflammatory mediators, TNF-α and IL-1β, were involved. Further, the combination of modafinil and gabapentin improved the neuroprotective effect of gabapentin. So, modafinil might be a neuroprotective agent in the prevention of VCR-induced neuropathy.

Arthrocen, an avocado-soy unsaponifiable agent, improves acetic acid-induced colitis in rat by inhibition of NF-kB signaling pathway

The goal of the current study was to evaluate the anti-inflammatory effect of Arthrocen against acetic acid-induced colitis in rats. Acute inflammation was produced through intrarectal administration of 2 ml diluted acetic acid (4%) solution. All interventions were carried out for 5 days after colitis induction. Arthrocen was administered orally at doses of 30, 60, and 120 mg kg^-1  day^-1 . Then, macroscopic and microscopic studies were performed. Myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) activity were measured by biochemical and ELISA methods, respectively. Immunohistochemistry was done to investigate the expression of pNF-κB. The results of this study demonstrated that Arthrocen reduced macroscopic and microscopic damage compared to the acetic acid group. Furthermore, Arthrocen decreased the activity of MPO and TNF-α as well as the protein expression of pNF-kB in rat colon tissue. The results of the current study revealed the anti-inflammatory activity of Arthrocen in acetic acid mediated colon inflammation through suppressing the NF-κB pathway. PRACTICAL APPLICATIONS: Inflammatory bowel disease (IBD) is an immune-mediated chronic relapsing disorder affecting the gastrointestinal tract (GIT) characterized by chronic bowel inflammation. A plant-based dietary supplement containing avocado and soy unsaponifiable extracts in a ratio of 1:2 is known as Arthrocen. Arthrocen can be used as a complementary drug beside current drugs in clinical trials for the treatment of IBD.

Hepatoprotective Effects of Standardized Extracts from an Ancient Italian Apple Variety (Mela Rosa dei Monti Sibillini) against Carbon Tetrachloride (CCl4)-Induced Hepatotoxicity in Rats

The aim of this research was to examine the effect of the hydroalcoholic extracts from the peel (APE) and pulp (APP) of a traditional apple cultivar from central Italy (Mela Rosa dei Monti Sibillini) on CCl4-induced hepatotoxicity in rats. Phytoconstituents were determined by liquid chromatography-mass spectrometry (LC-MS) analysis showing an abundance of proanthocyanidins and flavonol derivatives together with the presence of annurcoic acid in APE. Wistar rats received APE/APP (30 mg/kg oral administration) for three days before CCl4 injection (2 mL/kg intraperitoneal once on the third day). Treatment with both APE and APP prior to CCl4 injection significantly decreased the serum levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP) and alanine aminotransferase (ALT) compared to the CCl4 group. Besides, pretreatment with APE reversed the CCl4 effects on superoxide dismutase (SOD), myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α) and interleukin-1beta (IL-1β) levels in liver tissue in rats and reduced tissue damage as shown in hematoxylin and eosin staining. These results showed that this ancient Italian apple is worthy of use in nutraceuticals and dietary supplements to prevent and/or protect against liver disorders.

Combined chemo-magnetic field-photothermal breast cancer therapy based on porous magnetite nanospheres

The efficacy of different modalities of treating breast cancer is inhibited by several limitations such as off-targeted drug distribution, rapid drug clearance, and drug resistance. To overcome these limitations, we developed Lf-Doxo-PMNSs for combined chemo-MF-PTT. The PMNSs were synthesized by hydrothermal method and their physicochemical properties were examined by FE-SEM, TEM, DLS, TGA, XRD investigations. The cytotoxicity of as-synthesized NPs against 4T1 cells was carried out by MTT and flow cytometry assays. Afterwards, the anti-cancer activities of as-synthesized Lf-Doxo-PMNSs on the tumor status, drug distribution and apoptosis mechanism were evaluated. The anti-cancer assays showed that Lf-Doxo-PMNSs significantly suppressed the cancer cell proliferation and tumor weight by prolonging drug availability and potential drug loading in tumor cells; whereas they showed a minimum cytotoxicity against non-cancerous cells. Likewise, combined chemo-MF-PTT using Lf-Doxo-PMNSs displayed the highest anti-cancer activity followed by combined chemo-PTT and combined chemo-MF therapy based on altering the apoptosis mechanism. Therefore, these results showed that combined chemo-MF-PTT based on Lf-Doxo-PMNSs can be used as a promising therapeutic platform with potential targeted drug delivery and high loading capacity features as well as reducing cancer drug resistance.

Evaluation of the effects of metformin administration on morphine tolerance in mice

Opioids are used in clinical practice to relieve moderate to severe pain. Prolonged use of opioids can lead to a situation of analgesic tolerance and dependence. Several mechanisms are involved in the tolerance to analgesic opioids, including desensitization or internalization of the opioid receptor, elevation of cAMP levels, microglial activation and neuroinflammation, elevation of spinal mTOR activity and change in the expression of some proteins involved in tolerance, such as nNOS. Activation of the AMPK pathway inhibits mTOR and p38 MAPK ameliorating neuroinflammation and tolerance induced by morphine. Metformin, a potent antidiabetic agent, can also activate AMPK. Morphine tolerance was induced in mice by intraperitoneal administration three times daily at 08:00, 11.00 and 16.00 h of 50, 50 and 75 mg/kg morphine, respectively during four days. On the fifth day mice received a single injection of morphine 50 mg/kg. To evaluate the effects of metformin in development of morphine-induced analgesic tolerance a group of mice received metformin (10 mg/kg) 45 min before each morphine administration. Tail flick and hot plate tests were performed to estimate analgesic latency on days 1, 3 and 5. At five days, the animals were sacrificed, the brain dissected and nitrite levels determined. Chronic metformin administration significantly increased the analgesic latency on days 3 and 5 compared to the morphine group in hot plate test and in tail flick test. Chronic and acute metformin administration significantly decreased nitric oxide level compare to morphine group. The present results revealed that metformin attenuated analgesic tolerance induced by repeated intraperitoneal injections of morphine in mice.

Correction: Protective effects of hydroalcoholic extracts from an ancient apple variety ‘Mela Rosa dei Monti Sibillini’ against renal ischemia/reperfusion injury in rats

Correction for ‘Protective effects of hydroalcoholic extracts from an ancient apple variety ‘Mela Rosa dei Monti Sibillini’ against renal ischemia/reperfusion injury in rats’ by Hasan Yousefi-Manesh et al., Food Funct., 2019, 10, 7544–7552.

Protective effects of hydroalcoholic extracts from an ancient apple variety 'Mela Rosa dei Monti Sibillini' against renal ischemia/reperfusion injury in rats

The purpose of this work was to investigate the effect of hydroalcoholic extracts from the peel (APE) and pulp (APP) of a traditional apple variety of central Italy, the 'Mela Rosa dei Monti Sibillini', on the damage caused by renal ischemia/reperfusion injury (IRI) in rats. Thirty mg per kg b.w. of the extracts were administered intraperitoneally to male adult Wistar rats 3 days before the induction of IRI by pedicle clamping. A significant decrease in the levels of malondialdehyde (MDA), tumor necrosis factor-α (TNFα), interleukin 1 beta (IL-1β) and nuclear factor-κB (NF-κB) was observed in the groups pre-treated with APE when compared with IRI rats. The chemical composition of APE was determined by HPLC-DAD-MSⁿ highlighting a significant amount of proanthocyanidins (52.9 mg g^-1), flavonols (42.27 mg g^-1) and dihydrochalcones (11.75 mg g^-1). These findings indicated that this ancient apple variety is a promising source of nutraceuticals and functional foods helpful to manage complications of renal disorders.

Hepatoprotective effects of phosphatidylserine liposomes on carbon tetrachloride-induced hepatotoxicity in rats

It has been proposed carbon tetrachloride (CCl₄ ) intoxication due to the production of free radicals and serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) overload results hepatotoxicity. Phosphatidylserine (PS) has shown antioxidant activity in numerous studies. Therefore, this study was aimed to investigate the effects of PS liposomes treatment against the CCl₄ -induced hepatotoxicity in a rat model. Male Wistar rats were treated with PS (10 mg/kg, oral) or phosphatidylcholine liposomes (PC) (10 mg/kg, oral) for 3 days before CCl₄ (2 ml/kg; ip once on the third day) injection. The serum level of ALT, AST, and ALP were measured. Also, antioxidant assays were performed. Administration of PS with CCl₄ significantly inhibited alterations in the serum levels of AST, ALP (^** P < 0.01), and ALT (^*** P < 0.001) compared with control group. Furthermore, measurement of malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) levels indicated that PS significantly reduced reactive oxygen species. The results of the present study showed the hepatoprotective effects of PS against CCl₄ -induced hepatotoxicity in rats.

The antidepressant effects of GM-CSF are mediated by the reduction of TLR4/NF-ĸB-induced IDO expression

BACKGROUND

Indoleamine 2, 3-dioxygenase 1 (IDO) is responsible for the progression of the kynurenine pathway. This pathway has been implicated in the pathophysiology of inflammation-induced depression in which conventional antidepressants are not effective. It has been reported that granulocyte-macrophage stimulating factor (GM-CSF) could interfere with the induction of IDO in septic patients. We hypothesized that GM-CSF could exert antidepressant effects through IDO downregulation in a model for acute inflammation-induced depression.

METHODS

To produce the model, lipopolysaccharide (LPS) (0.83 mg/kg) was administered intraperitoneally to mice. It has been well documented that LPS mediates IDO overexpression through TLR4/NF-ĸB signaling. In the treatment group, mice received GM-CSF (30 μg/kg, i.p.) thirty minutes prior to LPS injection. A validated selective serotonin reuptake inhibitor, fluoxetine (30 mg/kg i.p.), was also administered to an experimental group 30 min prior to LPS. Depressive-like behaviors were evaluated based on the duration of immobility in the forced swim test. To confirm that GM-CSF interferes with IDO induction in LPS treated mice, real-time PCR was used to quantify IDO mRNA expression. Furthermore, in order to study whether GM-CSF inhibits the TLR4/NF-ĸB signaling pathway, we measured levels ofpNF-ĸB and TLR4 by western blotting.

RESULTS

GM-CSF demonstrated significant antidepressant activity in the presence of LPS on immobility (p < .001) and latency (p = .010) times in the forced swim test. In contrast, fluoxetine did not show any antidepressant activity on either immobility (p = .918) or latency (p = .566) times. Furthermore, GM-CSF inhibited the increase in IDO mRNA (p = .032) and protein (p = .016) expression as a result of LPS administration. A similar trend was observed for TLR4 (p = .042) and pNF-ĸB (p = .026) expression as both proteins showed reduced expression levels in the GM-CSF-pretreated group compared to the untreated (LPS) group.

CONCLUSION

Our results propose a promising antidepressant effect for GM-CSF possibly through the downregulation of IDO expression. This remedying effect of GM-CSF could be attributed to decreased amounts of TLR4 and active NF-ĸB in the treated mice.